通信工程毕业设计外文翻译--下一代无线宽带的目标(4G—5G)
通信工程毕业设计 外文翻译
东华理工大学长江学院毕业设计外文翻译学生姓名:张伟学号:09323119专业:信息工程系别:信息工程指导教师:谌洪茂职称:讲师二0一三年六月五日OriginalOptical Fiber CommunicationsThe General System Communication may be broadly defined as the transfer of information from one point to another. When the information is to be conveyed over any distance a communication system is usually required. Within a communication system the information transfer is frequently achieved by superimposing or modulating the information onto an electromagnetic wave which acts as a carrier for the information signal. This modulated carrier is then transmitted to the required destination where it is received and the original information signal is obtained by demodulation. Sophisticated techniques have been developed for this process by using electromagnetic carrier waves operating at radio frequencies as well as microwave and millimeter w ave frequencies. However, ‘communication’ may also be achieved by using an electromagnetic carrier which is selected from the optical range of frequencies.An optical fiber communication system is similar in basic concept to any type of communication system.The communication system therefore consists of a transmitter or modulator linked to the information source, the transmission medium,and a receiver or demodulator at the destination point. In electrical communications the information source provides an electrical signal, usually derived from a message signal which is not electrical (e.g. sound), to a transmitter comprising electrical and electronic components which converts the signal into a suitable form for propagation over the trans-mission medium. This is often achieved by modulating a carrier, which, as mentioned previously, may be an electromagnetic wave. The transmission medium can consist of a pair of wires, a coaxial cable or a radio link through free space down which the signal is transmitted to the receiver, where it is transformed into the original electrical information signal (demodulated) before being passed to the destination.However, it must be noted that in any transmission medium the signal is attenuated, or suffers loss, and is subject to degradations due to contamination by random signals and noise, as well as possible distortions imposed by mechanisms within the medium itself. Therefore, in any communication system there is a maximum permitted distance between the transmitter and the receiver beyond which the system effectively ceases to give intelligible communication. For long-haul applications these factors necessitate the installation of repeaters or line amplifiers atintervals,both to remove signal distortion and to increase signal level before transmission is continued down the link.For optical fiber communications system shown in Figure (a) may be considered in slightly greater detail, as given in Figure (b).Fig(a) The general communication system(b)The optical fiber communication systemIn this case the information source provides an electrical signal to a transmitter comprising an electrical stage which drives an optical source to give modulation of the light wave carrier. The optical source which provides the electrical–optical conversion may be either a semiconductor laser or light-emitting diode (LED). The transmission medium consists of an optical fiber cable and the receiver consists of an optical detector which drives a further electrical stage and hence provides demodulation of the optical carrier. Photodiodes (p–n, p–i–n or avalanche) and, in some instances, phototransistors and photoconductors are utilized for the detection of the optical signal and the optical–electrical conversion. Thus there is a requirement for electrical interfacing at either end of the optical link and at present the signal processing is usually performed electrically.The optical carrier may be modulated using either an analog or digital information signal. In the system shown in Figure (b) analog modulation involves the variation of the light emitted from the optical source in a continuous manner. Withdigital modulation,however, discrete changes in the light intensity are obtained (i.e. on–off pulses).Although often simpler to implement, analog modulation with an optical fiber communication system is less efficient, requiring a far higher signal-to-noise ratio at the receiver than digital modulation. Also, the linearity needed for analog modulation is not always provided by semiconductor optical sources, especially at high modulation frequencies. For these reasons,analog optical fiber communication links are generally limited to shorter distances and lower bandwidth operation than digital links.Figure (c) shows a block schematic of a typical digital optical fiber link. Initially, the input digital signal from the information source is suitably encoded for optical transmission. The laser drive circuit directly modulates the intensity of the semiconductor laser with the encoded digital signal. Hence a digital optical signal is launched into the optical fiber cable. The avalanche photodiode (APD) detector is followed by a front-end amplifier equalizer or filter to provide gain as well as linear signal processing and noise bandwidth reduction.Fig(c)A digital optical fiber link using a semiconductor laser source and an avalanche photodiode(APD) detectorFinally, the signal obtained is decoded to give the original digital information. However, at this stage it is instructive to consider the advantages provided by light wave communication via optical fibers in com-parison with other forms of line and radio communication which have brought about the extensive use of such systems in many areas throughout the world.译文光纤通信一般来说把信息从一点传送到另一点就称为通信。
通信工程专业英语课文翻译
Technology of Modern CommunicationText A: BluetoothBluetooth wireless technology is a short-range communications technology intended to replace the cables connecting portable(轻便的)and fixed devices while maintaining high levels of security.The key features of Bluetooth technology are robustness(稳健), low power, and low cost .The Bluetooth specification defines a uniform structure for a wide range of devices to connect and communicate with each other.蓝牙无线技术是一种小范围无线通信技术,旨在保持高安全级的基础上,在便携式设备与固定设备之间实现无线连接。
蓝牙技术的主要特点是稳健,低功耗和低成本。
蓝牙规范定义了一个统一的结构,适用范围广的设备连接并相互沟通。
Bluetooth technology has achieved global acceptance such that any Bluetooth enable device, almost everywhere in the world, can connect to other Bluetooth enabled devices in proximity. Bluetooth enabled electronic devices connect and communicate wirelessly through short-range, ad hoc(特别)networks known as piconets Each device can simultaneously communicate with up to seven other devices within a single piconet. Each device can also belong to several piconets simultaneously. Piconets are established dynamically and automatically as Bluetooth enabled devices enter and leave radio proximity.蓝牙技术已取得全球认可,使得任何支持蓝牙的设备,几乎在世界各地,可以连接到其他支持蓝牙的邻近装置。
现代移动通信 毕业论文外文翻译 (2)
一、英文原文Modern mobile communication technologyIn now highly the information society, the information and the correspondence have become the modern society “the life”. The information exchange mainly relies on the computer correspondence, but corresponds takes the transmission method, with the sensing technology, the computer technology fuses mutually, has become in the 21st century the international society and the world economic development powerful engine. In order to of adapt the time request, the new generation of mobile communication technology seasonable and lives, the new generation of mobile communication technology is the people said that third generation's core characteristic is the wide band addressing turns on non-gap roaming between the rigid network and numerous different communications system's, gains the multimedia communication services.Along with the time progress, the technical innovation, people's life request's enhancement, the mobile communication technology renewal speed is quite astonishing, almost every other ten year mobile communication technology has a transformation update, from the 1980s “the mobile phone” to present's 3G handset, during has had two mobile communication technology transformation, transits from 1G AMPS to 2G GSM, from GSM to IMT-2000 (i.e. 3G technology). Knows modern on me the mobile communication technology to have the following several aspect important technology:1. wideband modulation and multiple access techniqueThe wireless high speed data transmission cannot only depend on the frequency spectrum constantly the expansion, should be higher than the present number magnitude at least in the frequency spectrum efficiency, may use three technologies in the physical level, namely OFDM, UWB and free time modulation code. OFDM with other encoding method's union, nimbly OFDM and TDMA, FDMA, CDMA, SDMA combines the multiple access technique.In the 1960s the OFDM multi-channel data transmission has succeeded uses in complex and the Kathryn high frequency military channels. OFDM has used in 1.6 M bit/s high bit rate digital subscriber line (HDSL), 6 M bit/s asymmetrical digital subscriber line (ADSL), 100 M bit/s really high speed figure subscriber's line (VDSL), digital audio frequency broadcast and digital video broadcast and so on. OFDM applies on 5 GHz provides 54 M bit/s wireless local network IEEE 802.11 a and IEEE 802.11g, high performance this region network Hi per LAN/2 and ETSI-BRAN, but also takes metropolitan area network IEEE 802.16 and the integrated service digit broadcast (ISDB-T) the standard. Compares with the single load frequency modulation system service pattern, the OFDM modulation service pattern needs to solve the relatively big peak even power ratio (PAPR, Peak to Average Power Ratio) and to the frequency shifting and the phase noise sensitive question.High speed mobile communication's another request is under the wide noise bandwidth, must demodulate the signal-to-noise ratio to reduce as far as possible, thus increases the cover area. May adopt the anti-fading the full start power control and the pilot frequency auxiliary fast track demodulation technology, like the frequency range anti-fading's Rake receive and the track technology, the OFDMA technology which declines from the time domain and the frequencyrange resistance time and the frequency selectivity, the link auto-adapted technology, the union coding technique.2. frequency spectrum use factor lift techniqueThe fundamental research pointed out: In the independent Rayleigh scattering channel, the data rate and the antenna several tenth linear relationships, the capacity may reach Shannon 90%. Is launching and the receiving end may obtain the capacity and the frequency spectrum efficiency gain by the multi-antenna development channel space. The MIMO technology mainly includes the spatial multiplying and the space diversity technology, concurrent or the salvo same information enhances the transmission reliability on the independent channel.Receives and dispatches the bilateral space diversity is the high-capacity wireless communication system uses one of technical. Bell Lab free time's opposite angle BLAST (D-BLAST) capacity increase to receive and dispatch the bilateral smallest antenna number in administrative levels the function. The cross time domain which and the air zone expansion signal constitutes using MIMO may also resist the multi-diameter disturbance. V-BLAST system when indoor 24~34 dB, the frequency spectrum use factor is 20~40 bit/s/Hz. But launches and the receiving end uses 16 antennas, when 30 dB, the frequency spectrum use factor increases to 60~70 bit/s/Hz.The smart antenna automatic tracking needs the signal and the auto-adapted free time processing algorithm, produces the dimensional orientation wave beam using the antenna array, causes the main wave beam alignment subscriber signal direction of arrival through the digital signal processing technology, the side lobe or zero falls the alignment unwanted signal direction of arrival. The auto-adapted array antennas (AAA, Adaptive Array Antennas) disturbs the counter-balance balancer (ICE, Interference Canceling Equalizer) to be possible to reduce disturbs and cuts the emissive power.3. software radio technologyThe software radio technology is in the hardware platform through the software edition by a terminal implementation different system in many kinds of communication services. It uses the digital signal processing language description telecommunication part, downloads the digital signal processing hardware by the software routine (DSPH, Digital Signal Processing Hardware). By has the general opening wireless structure (OWA, Open Wireless Architecture), compatible many kinds of patterns between many kinds of technical standards seamless cut.UWB is also called the pulse to be radio, the modulation uses the pulse width in the nanosecond level fast rise and the drop pulse, the pulse cover frequency spectrum from the current to the lucky hertz, does not need in the radio frequency which the convention narrow band frequency modulation needs to transform, after pulse formation, may deliver directly to the antenna launch.4. software radio technologyThe software radio technology is in the hardware platform through the software edition by a terminal implementation different system in many kinds of communication services. It uses the digital signal processing language description telecommunication part, downloads the digital signal processing hardware by the software routine (DSPH, Digital Signal Processing Hardware). By has the general opening wireless structure (OWA, Open Wireless Architecture), compatible many kinds of patterns between many kinds of technical standards seamless cut.5. network security and QoSQoS divides into wireless and the wired side two parts, wireless side's QoS involves theradio resource management and the dispatch, the admission control and the mobility management and so on, the mobility management mainly includes the terminal mobility, individual mobility and service mobility. Wired side's QoS involves based on the IP differ discrimination service and the RSVP end-to-end resources reservation mechanism. Mechanism maps the wireless side IP differ IP the QoS. Network security including network turning on security, core network security, application security, safety mechanism visibility and configurable.In the above modern mobile communication key technologies' foundation, has had the land honeycomb mobile communication, the satellite communication as well as the wireless Internet communication, these mailing address caused the correspondence appearance to have the huge change, used the digital technique the modern wireless communication already to permeate the national economy each domain and people's daily life, for this reason, we needed to care that its trend of development, hoped it developed toward more and more convenient people's life's direction, will let now us have a look at the modern mobile communication the future trend of development.modern mobile communication technological development seven new tendencies :First, mobility management already from terminal management to individual management and intelligent management developmentSecond, network already from synchronized digital circuit to asynchronous digital grouping and asynchronous transfer mode (ATM) development;the three, software's developments actuated from the algorithm to the procedure-oriented and face the goal tendency development;the four, information processing have developed from the voice to the data and the image;five, wireless frequency spectrum processing already from narrow band simulation to the narrow band CDMA development;the six, computers have developed from central processing to the distributional server and intellectualized processing;the seven, semiconductor devices have developed from each chip 16,000,000,000,000 /150MHz speed VLSI to 0.5 /350MHz speed VLSI and 2,000,000,000,000,000 /550MHz speed VLSI.Under this tendency's guidance, the mobile service rapid development, it satisfied the people in any time, any place to carry on the correspondence with any individual the desire. The mobile communication realizes in the future the ideal person-to-person communication service way that must be taken. In the information support technology, the market competition and under the demand combined action, the mobile communication technology's development is progresses by leaps and bounds, presents the following several general trends: work service digitization, grouping; 2. networking wide band; working intellectualization; 4.higher frequency band; 5. more effective use frequency; 6.each kind of network tends the fusion. The understanding, grasps these tendencies has the vital practical significance to the mobile communication operator and the equipment manufacturer.二、英文翻译现代移动通信在当今高度信息化的社会,信息和通信已成为现代社会的“命脉”。
无线通信外文翻译
无线通信外文翻译南京工程学院毕业设计文献资料翻译,原文及译文,原文名称: Wireless Communications课题名称: 无线电子门铃设计学生姓名: 顾玲玲学号: 208080603 指导老师: 马新华所在系部: 通信工程学院专业名称: 电子信息工程2012 年 3 月南京Wireless CommunicationsModern computer technology, industrial revolution, the world economy from the capital into the economy to knowledge economy. Field in the electronic world, fromthstthe 20 century into the era of radio to computer technology in the 21 century as thecenter of the intelligent modern era of electronic systems. Thebasic core of modern electronic systems are embedded computer systems (referred to as embedded systems), while the microcontroller is the most typical and most extensive and most popular embedded systems.Fist, radio has created generations of excellence in the world.thFifties and sixties in the 20 century, the most representative of the advancedelectronic, technology is wireless technology, including radio broadcasting, radio, wireless communications (telegraph) ,Amateur Radio,radio positioning, navigation and other telemetry, remote control, remote technology. Early that these electronic technology led many young people into the wonderful digital world, radio show was a wonderful life, the prospects for science and technology. Electronics began to form a new discipline. Radio electronics, wireless communications began e-world journey. Radio technology not only as a representative of advanced science and technology at that time, but also from popular to professional fields of science, attracting the young people and enable them to find a lot of fun. Ore from the bedside to the superheterodyne radio; report issued from the radio amateur radio stations; from the telephone, electric bell to the radio control model. Became popularyouth radio technology, science and technology education is most popular and most extensive content. So far, many of the older generation of engineer, experts. Professor of the year are radio enthusiasts. Funradio technology, radio technology, components to the radio-based remote control, telemetry, remote electronic systems, has trained several generations of technological excellence.Second, from the popularity of the radio era to era of electronic technology. The early radio technology to promote the development of electronic technology, most notably electronic vacuum tube technology to semiconductor electronic technology, Semiconductor technology to realize the active device miniaturization and low cost, so more popular with radio technology and innovation, and to greatly broaden the number ofnon-radio-control areas. The development of semiconductor technologyleads to the production of integrated circuits. Electronic design engineers1no longer use the discrete electronics components designed circuit modules, and direct selection of integrated circuit componentsconstitute a single system. They freed the design of the circuit unit dedicated to system design, greatly liberating the productive forces of science and technology; promote the wider spread of electronic systems. Semiconductor integrated circuits in the basic digital logic circuits first breakthrough. A large number of digital logic circuits, such as gates, counters, timers, shift registers, and analog switches, comparators, etc., for the electronic digital control provides excellent conditions for the traditional mechanical control to electronic control. Power electronic devices and sensor technology to make the original to the radio as the center of electronic technology turned to mechanical engineering in the field of digital control systems, testing in thefield of information collection, movement of electrical mechanical servo drive control object. Semiconductor and integrated circuit thunit-specific electronic technology a part of. 70 years into the20 century, large scaleintegrated circuit appeared to promote the conventional electronic circuit unit-specific electronic systems development. Many electronic systems unit into a dedicated integrated device such as radios, electronic clocks, calculators, electronic engineers in these areas fromthe circuit, the system designed to debug into the device selection, peripheral device adapter work. Electronic technology, and electronic products enriched, electronic engineers to reduce the difficulty, but at the same time, radio technology, electronic technology has weakened the charm. The development of semiconductor integrated circuits classical electronic systems are maturing, remain in the large scale integrated circuit other than the shrinking of electronic technology, electronic technology is not the old days of radio fun times and comprehensive engineering training.Third, from the classic era of electronic technology to modern electronic technology of the times.th80 years into the 20 century of economic change is most important revolution inthe computer. The computer revolution in the most important sign is the birth of the computer embedded applications. Modern computer numerical requirements should be born. A long period of time is to develop the massive computer numerical duty. But the computer shows the logic operation, processing, control, attracting experts in the filed of electronic control, they want development to meet the control, object requirements of embedded applications computer systems. If you meet the massive data-processing computer system known as general-purpose computer system, then2the system can be the embedded object(such as ships, aircraft, motorcycles, etc.) in a computer system called the embedded computer. Clearly, both the direction of technology development is different. The former requires massive data storage, handling, processing and analysis of high-speed data transmission; while the latter requires reliable operation in the target environment, the external physical parameters on high-speed acquisition, analysis and processing logic and the rapid control of external objects. It will add an early general-purpose computer data acquisition unit, the output driver circuit reluctance to form a heat treatment furnace temperature control system. This general-purpose computer system is not possible for most of the electronic system used, and to make general-purpose computer system meets the requirements of embedded applications, will inevitably affect the development of high-speed numeric processing. In order to solve the contradiction between thethdevelopment of computer of computer technology, in the 20 century 70s.,semiconductor experts another way, in full accordance with the electronic system embedded computer application requirements, a micro-computer’s basic system on achip, the formation of early SCM(single Chip Microcomputer). After the advent of single chip in the computer industry began to appear in the general-purpose computer systems and embedded systems the two branches. Since then, both the embedded system, and general-purposecomputer systems have been developed rapidly. Although the early general-purpose computer converted the embedded system began in the emergence of SCM. Because the microcontroller is designed specifically for embedded applications, the MCU can only achieve embedded applications. MCU embedded applications that best meet environmental requirements, for example, chip-level physical space, large-scale instruction. A computer system microcontroller core embedded electronic systems, intelligent electronic systems for the foundation. Therefore, the current single chip electronic system in widespread use of electronic systems to enable rapid transition to the classical modern intelligent electronic systems.译文无线通信从无线电世界到单片机世界,现代计算机技术的产业革命将世界经济从资本经济带入到知识经济时代。
无线通信毕业设计外文翻译
Wireless communicationModern computer technology, industrial revolution, the world economy from the capital into the economy to knowledge economy. Field in the electronic world, from the 20th century into the era of radio to computer technology in the 21st century as the center of the intelligent modern era of electronic systems. The basic core of modern electronic systems are embedded computer systems (referred to as embedded systems), while the microcontroller is the most typical and most extensive and most popular embedded systems.First, radio has created generations of excellence in the worldFifties and sixties in the 20th century, the most representative of the advanced electronic technology is wireless technology, including radio broadcasting, radio, wireless communications (telegraph), Amateur Radio, radio positioning, navigation and other telemetry, remote control, remote technology. Early that these electronic technology led many young people into the wonderful digital world, radio show was a wonderful life, the prospects for science and technology. Electronics began to form a new discipline. Radio electronics, wireless communications began e-world journey. Radio technology not only as a representative of advanced science and technology at that time, but also from popular to professional fields of science, attracting the young people and enable them to find a lot of fun. Ore from the bedside to the superheterodyne radio radio; report issued from the radio amateur radio stations; from the telephone, electric bell to the radio control model. Became popular youth radio technology, science and technology education is the most popular and most extensive content. So far, many of the older generation of engineers, experts, Professor of the year are radio enthusiasts. Fun radio technology, radio technology, comprehensive training, from basic principles of electronics, electronic components to the radio-based remote control, telemetry, remote electronic systems, has trained several generations of technological excellence.Second, from the popularity of the radio era to era of electronic technologyThe early radio technology to promote the development of electronic technology, most notably electronic vacuum tube technology to semiconductor electronictechnology. Semiconductor technology to realize the active device miniaturization and low cost, so more popular with radio technology and innovation, and to greatly broaden the number of non-radio-control areas. The development of semiconductor technology lead to the production of integrated circuit, forming the modern electronic technology leap from discrete electronics into the era of era of integrated circuits. Electronic design engineers no longer use the discrete electronic components designed circuit modules, and direct selection of integrated circuit components constitute a single system. They freed the design of the circuit unit dedicated to system design, greatly liberating the productive forces of science and technology, promote the wider spread of electronic systems. Semiconductor integrated circuits in the basic digital logic circuits first breakthrough. A large number of digitallogic circuits, such as gates, counters, timers, shift registers, and analog switches, comparators, etc., for the electronic digital control provides excellent conditions for the traditional mechanical control to electronic control. Power electronic devices and sensor technology to make the original to the radio as the center of electronic technology turned to mechanical engineering in the field of digital control systems, testing in the field of information collection, movement of electrical mechanical servo drive control object. Semiconductor and integrated circuit technology will bring us a universal age of electronic technology, wireless technology as the field of electronic technology a part of. 70 years into the 20th century, large scale integrated circuit appeared to promote the conventional electronic circuit unit-specific electronic systems development. Many electronic systems unit into a dedicated integrated devices such as radios, electronic clocks, calculators, electronic engineers in these areas from the circuit, the system designed to debug into the device selection, peripheral device adapter work. Electronic technology, and electronic products enriched, electronic engineers to reduce the difficulty, but at the same time, radio technology, electronic technology has weakened the charm. The development of semiconductor integrated circuits classical electronic systems are maturing, remain in the large scale integrated circuit other thanthe shrinking of electronic technology, electronic technology is not the old days of radio fun times and comprehensive engineering training.Third, from the classic era of electronic technology to modern electronic technology of the times80 years into the 20th century, the century of economic change is the most important revolution in the computer. The computer revolution in the most important sign is the birth of the computer embedded applications. Modern computer numerical requirements should be born. A long period of time, is to develop the massive computer numerical duty. But the computer shows the logic operation, processing, control, attracting experts in the field of electronic control, they want development to meet the control object requirements of embedded applications, computer systems. If you meet the massive data-processing computer system known as general-purpose computer system, then the system can be the embedded object (such as ships, aircraft, motorcycles, etc.) in a computer system called the embedded computer. Clearly, both the direction of technology development are different. The former requires massive data storage, handling, processing and analysis of high-speed data transmission; while the latter requires reliable operation in the target environment, the external physical parameters on high-speed acquisition, analysis and processing logic and the rapid control of external objects. It will add an early general-purpose computer data acquisition unit, the output driver circuit reluctance to form a heat treatment furnace temperature control system. This general-purpose computer system is not possible for most of the electronic system used, and to make general-purpose computer system meets the requirements of embedded applications, will inevitably affect the development of high-speed numeric processing. In order to solve the contradiction between the development of computer technology, in the 20th century 70s, semiconductor experts another way, in full accordance with the electronic systemembedded computer application requirements, a micro-computer's basic system on a chip, the formation of the early SCM (Single Chip Microcomputer). After the advent of single chip in the computer industry began to appear in the general-purpose computer systems and embedded systems the two branches. Since then, both the embedded system, or general-purpose computer systems have been developed rapidly.Although the early general-purpose computer converted the embedded computer systems, and real embedded system began in the emergence of SCM. Because the microcontroller is designed specifically for embedded applications, the MCU can only achieve embedded applications. MCU embedded applications that best meet environmental requirements, for example, chip-level physical space, large-scale integrated circuits low-cost, good peripheral interface bus and outstanding control of instruction. A computer system microcontroller core, embedded electronic systems, intelligent electronic systems for the foundation. Therefore, the current single chip electronic system in widespread use of electronic systems to enable rapid transition to the classical modern intelligent electronic systems.Forth, single chip to create the modern era of electronic systems.A microcontroller and embedded systems Embedded computer systems from embedded applications, embedded systems for early general-purpose computer adapted to the object system embedded in a variety of electronic systems, such as the ship's autopilot, engine monitoring systems. Embedded system is primarily a computer system, followed by it being embedded into the object system, objects in the object system to achieve required data collection, processing, status display, the output control functions, as embedded in the object system, embedded system computer does not have an independent form and function of the computer. SCM is entirely in accordance with the requirements of embedded system design, so SCM is the most typical embedded systems. SCM is the early application of technical requirements in accordance with the design of embedded computer chip integration, hence the name single chip. Subsequently, the MCU embedded applications to meet the growing demands of its control functions and peripheral interface functions, in particular, highlight the control function, so has international name the single chip microcontroller (MCU, Microcontroller Unit).2 MCU modern electronic systems consisting of electronic systems will become mainstreamMCU is a device-level computer systems, it can be embedded into any object system to achieve intelligent control. Small to micro-machinery, such as watches,hearing aids.Low-cost integrated device-level, low-to a few dollars, ten dollars, enough to spread to many civilian SCM appliances, electronic toys to go. SCM constitutes a modern electronic systems has in-depth to the households, are changing our lives, such as home audio, televisions, washing machines, microwave ovens, telephones, security systems, and air conditioners. SCM innovation the original electronic systems, such as microwave ovens use SCM, it can easily set the clock, the program memory, power control; air conditioner after use of SCM is not only convenient for remote parameter setting, running automatically transform, frequency control can be achieved.At present, many household appliances such as VCD, DVD only single chip to achieve its function may occur before. 3 Embedded Systems led the entire electronics industry Current electronic components industry, in addition to microprocessors, embedded system devices, the most modern electronic systems around the supporting components industries, such as keys used to meet the human-computer interaction, LED / LCD display drivers, LED / LCD display units, voice integrated device, etc., to meet the requirements of data acquisition channel digital sensor, ADC, data acquisition module, signal conditioning modules to meet the servo drive control in the DAC, solid state relays, stepper motor controller, frequency control unit, etc., to meet the communication requirements various bus driver, level converters. Electronic components in the embedded systems world, driven by embedded applications along fully meet requirements of modern electronic systems development. This makes the original classic world of increasingly small electronic systems. Practitioners in the various electronic systems to modern electronic systems as early as possible to stay.Fifth, SCM will create a new generation of electronic elite.If the 50's, radio has created several generations of the world elite, then today's SCM will create a new generation of e-world elite. A single chip with you to the intelligent electronics If we as a dead classic electronic system electronic system, then the intelligent modern electronic systems is a "life" of the electronic system. Application System of hardware, electronic systems, "body", microcontroller applications, the applicationgives it "life." For example, in the design of intelligent machines monitor display, it can boot the system self-test results show, not to enter the work shows a variety of stand-by state, equipment run-time display running processes, work can be displayed after the end of the current results, self results, raw data, reports and other various processing. Unattended, it can run automatically given a variety of functions. Intelligent electronic systems for the endless realm, often without additional hardware resources can achieve all kinds of renovated function. It is also present in many household appliances feature a large number of additional factors. 2 single chip computer with you to the industrial area The 21st century is the century of humanity into the computer age, many people are not used in the manufacture of computer is the computer. People using the computer, only the people engaged in embedded system applications really into the internal computer system hardware and software systems, can we truly understand the nature of the computer's intelligence and grasp the knowledge of intelligent design. MCU applications starting from the learning technology applications in today's computer software training, hardware and technical personnel of one of the best roads. 3 SCM bring you into the most attractive in the digital world Charming single chip to enable you to experience the true meaning of the computer, you can design intelligent microcontroller hands-on toys, different applications can be designed to achieve different functions. Both software design and hardware making there, both mental and physical, but also hands. Primary level can develop intelligent toys, with macro programming. Intermediate levels can develop some intelligent controller, such as computer mouse, smart cars, all kinds of remote control model. High levels can be developed robots, such as robot soccer, the development of industrial control units, network communications, and high-levellanguage with assembly language or design application. Microcontroller and embedded systems around the formation of the future of the electronics industry, will provide a vast world of electronic fans, an even broader than the current wireless world, richer, more durable, more attractive in the digital world. Plunge into the microcontroller in the world to, will benefit your life.MCU AttacksCurrently, there are four single chip attack technique, namely: (1) software attack The technology is commonly used processor communication interface and use protocol, encryption algorithm or the algorithm of security vulnerabilities to attack. The success of software attack is a typical example of the early ATMEL AT89C MCU attacks. Attacker single chip erase operation of the timing design flaw, erase the encryption used by ourselves locked in place, the next stop on-chip program memory data erase operation, thus bringing into too close a single chip SCM not encrypted, and then use the programmer to read out chip program. (2) electronic detection of attacks The technology is usually a high time resolution to monitor the processor during normal operation of all power and interface simulation features, and by monitoring the electromagnetic radiation characteristics of it to attack. Because SCM is an active electronic device, when it executes a different command, the corresponding changes in the power consumption accordingly. This through the use of special electronic measuring instruments and mathematical statistical analysis and detection of these changes, you can access key information specific microcontroller.(3) fault generation technology Abnormal working conditions of the technology used to make the processor errors, and provide additional access to attack. Produce the most widely used means of attack, including the fault of the impact and the clock voltage shock. Low voltage and high voltage protection circuit attack can be used to prohibit the work of processor execution errors or enforcement action. Clock transition may reset the transient protection circuit will not damage the protected information. Power and clock transients transition effects in certain single-processor instruction decoding and execution. (4) probe This technology is directly exposed to chip connection, and then observe, manipulate, interfere with single chip to achieve the attack purpose. For convenience, these four people will attack techniques are divided into two categories is theintrusion type attack (physical attack), such attack requires destruction of package, then use semiconductor test equipment, microscopes and micro-positioning device, in a special laboratory spend hours or even weeks to complete. All of the micro-probe techniques are invasive type attack. The other three methods are non-invasive type attack, attack the MCU will not be physical damage. In some cases, non-invasive-type attacks are particularly dangerous, but because of non-invasive type attacks can usually be made and the necessary equipment to upgrade, so it is cheap. Most non-invasive type attack requires the attacker have a good knowledge of processors and software knowledge. In contrast, the invasive type of probe do not need too much of the initial attack of knowledge, and usually a set of similar technology available to deal with a wide range of productsMCU general process of invasion-type attackInvasive type of attack is thrown off its first chip package. There are two ways to achieve this goal: the first one is completely dissolved out chip package, exposed metal connections. The second is only removed to the top of the plastic package silicon core. The first method is the need to bind to the test fixture on the chip, using bind Taiwan to operate. The second method requires the attacker in addition to a certain degree of knowledge and necessary skills, but also the wisdom and patience, but operate relatively easy. Above the plastic chips can be opened with a knife, epoxy around the chip can be eroded by concentrated nitric acid. Hot concentrated nitric acid will dissolve out without affecting the chip, chip packaging and connection. This process usually very dry conditions, because the presence of water may erode the aluminum wire connections have been exposed. Then, in ultrasonic cleaning of the pool first chip with acetone to remove residual nitric acid, then washed with water to remove salt and dried. No ultrasound pool, are generally skip this step. This case, the chip surface, a bit dirty, but do not affect the operation of UV effects on the chip. The final step is to find the location of the protection fuse and fuse protection under exposure to UV light. General use at least a 100 times magnification microscope, from the programming voltage input pin of the connection tracking in, to find protection fuse. If there is no microscope, theuse of different parts of the chip is exposed to ultraviolet light and observe the results under the simple search mode. Operation applied opaque paper cover to protect the program memory chips are not erased by ultraviolet light. Will protect the fuse exposed under UV light 5 to 10 minutes to destroy the protection bit of the protective effect, use a simple programmer can directly read the contents of program memory. The use of the protective layer to protect the MCU EEPROM cell, using ultraviolet light reset protection circuit is not feasible. For this type of MCU, the general use of micro-probe technology to read the memory contents. In the chip package is opened, the chip placed under the microscope can easily find from the memory circuit connected to other parts of the data bus. For some reason, the chip lock-bit programming mode is not locked in the memory of the visit. Advantage of this flaw on the data lines to probe the above data can be read all you want. In programming mode, restart the process of reading and connect probe to the other data can be read online program and data memory, all of the information. There is also a possible means of attack is the use of microscopy and laser cutting machines and other equipment to find the fuse protection to this part of the circuit tracing and linking all the signal lines. Because of the design defects, so long as cut off from other circuit protection fuse to a one signal line, you can ban the entire protection. For some reason, this thread is very far from the other line, so the use of laser cutting machine can cut the wire without affecting the adjacent line. In this way, using a simple programmer can directly read the contents of program memory. Although the most common single chip microcontroller has fuse blown inside the code protection features, but because of general low-end MCU is not positioning the production of safe products, so they often do not provide targeted preventive measures and the low level of security. MCU applications with a broad, large sales volume, commission processing and transfer of technology between firms frequently spilled a lot oftechnical data, making use of loopholes in the design of such chips and test interface manufacturer, and by modifying the invasive type fuse protection bits, etc. means of attack or invasion-type attack to read MCU's internal procedureshave become easier.About common single chipSTC microcontroller STC's mainly based on the 8051 microcontroller core is a new generation of enhanced MCU, the instruction code is fully compatible with the traditional 8051, 8 to 12 times faster, with ADC, 4 Road, PWM, dual serial ports, a global unique ID, encryption of good, strong anti-interference. PIC Microcontroller: MICROCHIP's products is its prominent feature is a small, low power consumption, reduced instruction set, interference, reliability, strong analog interface, the code of confidentiality is good, most of the chip has its compatibleFLASH program memory chips. EMC SCM: Elan's products in Taiwan, with much of the PIC 8-bit microcontroller compatible, and compatible products, resources, compared to the PIC's more, cheap, there are many series of options, but less interference. ATMEL microcontroller (MCU 51): ATMEl company's 8-bit microcontroller with AT89, AT90 two series, AT89 series is the 8-bit Flash microcontroller 8051 is compatible with the static clock mode; AT90 RISC MCU is to enhance the structure, all static methods of work, containing the line can be Flash MCU programming, also known A VR microcontroller. PHLIPIS 51PLC Microcontroller (MCU 51): PHILIPS company's MCU is based on the 80C51 microcontroller core, embedded power-down detection, simulation and on-chip RC oscillator and other functions, which makes 51LPC in highly integrated, low cost, low power design to meet various applications performance requirements. HOLTEK SCM: Sheng Yang, Taiwan Semiconductor's single chip, cheap more categories, but less interference for consumer products. TI company microcontroller (MCU 51):Texas Instruments MSP430 provides the TMS370 and two series of general-purpose microcontroller. TMS370 MCU is the 8-bit CMOS MCU with a variety of storage mode, a variety of external interface mode, suitable for real-time control of complex situations; MSP430 MCU is a low power, high functionality integrated 16-bit low-power microcontroller, especially for applications that require low power consumption occasions Taiwan Sonix's single, mostly 8-bit machines, some with PIC 8-bit microcontroller compatible, cheap, the system clock frequency may be more options there PMW ADC internal noise filtering within the vibration. Shortcomings RAM space is too small, better anti-interference.无线通信从无线电世界到单片机世界现代计算机技术的产业革命,将世界经济从资本经济带入到知识经济时代。
5G无线通信网络中英文对照外文翻译文献
5G无线通信网络中英文对照外文翻译文献(文档含英文原文和中文翻译)翻译:5G无线通信网络的蜂窝结构和关键技术摘要第四代无线通信系统已经或者即将在许多国家部署。
然而,随着无线移动设备和服务的激增,仍然有一些挑战尤其是4G所不能容纳的,例如像频谱危机和高能量消耗。
无线系统设计师们面临着满足新型无线应用对高数据速率和机动性要求的持续性增长的需求,因此他们已经开始研究被期望于2020年后就能部署的第五代无线系统。
在这篇文章里面,我们提出一个有内门和外门情景之分的潜在的蜂窝结构,并且讨论了多种可行性关于5G无线通信系统的技术,比如大量的MIMO技术,节能通信,认知的广播网络和可见光通信。
面临潜在技术的未知挑战也被讨论了。
介绍信息通信技术(ICT)创新合理的使用对世界经济的提高变得越来越重要。
无线通信网络在全球ICT战略中也许是最挑剔的元素,并且支撑着很多其他的行业,它是世界上成长最快最有活力的行业之一。
欧洲移动天文台(EMO)报道2010年移动通信业总计税收1740亿欧元,从而超过了航空航天业和制药业。
无线技术的发展大大提高了人们在商业运作和社交功能方面通信和生活的能力无线移动通信的显著成就表现在技术创新的快速步伐。
从1991年二代移动通信系统(2G)的初次登场到2001年三代系统(3G)的首次起飞,无线移动网络已经实现了从一个纯粹的技术系统到一个能承载大量多媒体内容网络的转变。
4G无线系统被设计出来用来满足IMT-A技术使用IP面向所有服务的需求。
在4G系统中,先进的无线接口被用于正交频分复用技术(OFDM),多输入多输出系统(MIMO)和链路自适应技术。
4G无线网络可支持数据速率可达1Gb/s的低流度,比如流动局域无线访问,还有速率高达100M/s的高流速,例如像移动访问。
LTE系统和它的延伸系统LTE-A,作为实用的4G系统已经在全球于最近期或不久的将来部署。
然而,每年仍然有戏剧性增长数量的用户支持移动宽频带系统。
无线通信5G介绍英文论文 A Brief Introduction About 5G Network
A Brief Introduction About 5G Network JiaAbstractWith the rapid development of wireless technologies, theconcept of the Fifth Generation (5G) wireless communication system started to emerge. But most people know little about 5G,including some aspects of 5G wireless communication networks ,just like what 5G is about: what are the building blocks of core 5G system concept, what are the main challenges and how to tackle them. Besides,A number of countries and organizations working on 5G, 5G development situation in China is of concern to everyone, China also needs to have its own place in such a competitive environment. Keywords:5G Network, history,Core concept, Challenges, Solutions, In chinaTable of Content1. Introduction................................................................................................................. - 3 -2. Research and development history ............................................................................. - 3 -3. Core Concept .............................................................................................................. - 4 -4. Challenges and Solutions............................................................................................ - 5 - 4.1 5G Transport Challenge ........................................................................................ - 6 - 4.2 5G Transport Challenge and some Solutions........................................................ - 7 - 4.3 Machine to Machine Communication................................................................... - 7 - 4.3 Core Network Virtualisation ................................................................................. - 8 -4.4 Summary............................................................................................................... - 8 -5. 5G In China................................................................................................................. - 9 - 5.5.1 White paper........................................................................................................ - 9 - 5.5.2 5G standards ...................................................................................................... - 9 - 5.5.3 China communications companies .................................................................... - 9 -5.5.4 Summary.......................................................................................................... - 10 -6. Conlusion.................................................................................................................. - 10 -7. Acronyms.................................................................................................................. - 11 -8. References................................................................................................................. - 11 -1. Introduction5G (Fifth-generation mobile communications) is a new generation of mobile communication mobile communication systems for 2020, with high spectral efficiency and low power consumption, in terms of transfer rate and resource utilization improvement over 4G system 10 times, its wireless coverage performance and user experience will be significantly improved. 5G will be closely integrated with other wireless mobile communication technology, constitute a new generation of ubiquitous mobile information network, to meet future mobile Internet traffic 1000x development needs in 10 years.[1]In this paper I will show you some latest research and development history,what are the building blocks of core 5G system concept, what are the main challenges and how to tackle them firstly. In the rest of paper I will show how 5G development in China in recent years and my conclusion after research literature.2. Research and development historyFebruary 2013, the EU announced that it would grant 50 million euros to accelerate the development of 5G mobile technology, plans to launch a mature standard in 2020. [2][3]May 13,2013,South Korea's Samsung Electronics Co., Ltd. announced that it has successfully developed the 5th generation mobile communication (5G) core technology, which is expected to begin in 2020 to commercialization. The technology can transmit data at ultra-high frequency 28GHz to 1Gbps per second speed, and the maximum transmission distance of up to 2 km. In contrast, the current fourth generation Long Term Evolution (4GLTE) and services of only the transmission rate 75Mbps. Prior to the transmission bottleneck is widely believed that a technical problem, while Samsung Electronics is the use of 64 adaptive array antenna elements transmission technology to crack this problem. Compared with the transmission speed of 4G technology in South Korea, 5G technology is hundreds of times faster. Using this technique, download a high-definition (HD) movie just need 10 seconds.Back in 2009, Huawei has launched the early research related technologies, and to show the prototype of the 5G base in later years.In November 6, 2013,Huawei announced that it would invest $600 million in 2018 for the 5G technology development and innovation, and predicted that users will enjoy 20Gbps commercial 5G mobile networks in 2020. May 8, 2014, the Japanese telecom operator NTT DoCoMo announced officially, Ericsson ,Nokia, Samsung and other six manufacturers to work together, began testing override 1000 times than existing 4G networks the carrying capacity of the high-speed network 5G network, the transmission speed is expected to 10Gbps. Outdoor testing scheduled to commence in 2015, and expects to begin operations in 2020.[3]March 1, 2015, the British "Daily Mail" reported that the British 5G network has successfully developed and tested for data transmission within 100 meters per second data transfer of up to 125GB, is 6.5 times the 4G network, in theory, a 30 seconds to download movies, adding that investment in public test in 2018, 2020 officially put into commercial use.[4]February 11, 2015 in the afternoon news, IMT-2020 (5G) to promote the group (hereinafter referred to as "advance group") held a conference in Beijing 5G concept of white paper. White Paper from the mobile Internet and networking composed mainly of application scenarios, business needs and challenges of starting summed continuous wide area coverage, high reliability of the four major technology 5G scene of high capacity, low power consumption and low latency connection. Meanwhile, the combination of core technologies and key capabilities 5G and 5G concept proposed by the "flag sexuality index + a set of key technologies" common definition.March 3,2015,the European Economic and Social Commission for Digital Furusawa Ottinge officially announced the EU's vision of public-private partnerships 5G, and strive to ensure that the right to speak in the next generation of mobile technology in Europe in the global standard.Ottinger said that, 5G vision of public-private partnership involves not only fiber, wireless or satellite communications network integrated with each other, will also use the software-defined networking (SDN), network functions virtualization (NFV), Mobile Edge computing (MEC) and Fog Computing technology. In the spectrum, the EU's vision of public-private partnership will be designated 5G hundreds of megahertz to improve network performance, 60 GHz and higher frequency bands will also be taken into account.A number of countries and organizations announced, 5G network will be operational between 2020 ~ 2025.3. Core ConceptWhat is 5G? I believe many people will be so questionable when see 5G. Judging from the word meaning, 5G refers to the fifth generation of mobile communications. However, how should it define? Currently, the global industry for 5G concept not yet agreed. China IMT-2020 (5G) group released the White Paper considers the concept 5G, 5G integrated key capabilities and core technology, 5G concept by "important targets" and "a group of key technologies" to a common definition. Among them, the flag indicators "Gbps rate user experience" is a set of key technologies, including large-scale antenna array, ultra-dense networking, new multi-site, full-spectrum access and new network architectures.Recalling the course of development of mobile communications, each generation ofmobile communication systems can be defined by sexual performance indicators and signs of key technologies. Wherein, 1G using FDMA, only analog voice services; 2G mainly using TDMA, can provide voice and low -speed digital data services; 3G to CDMA technology is characterized by user peak rate of 2Mbps to reach tens of Mbps, support multimedia data services; 4G OFDMA technology as the core, the user peak rate of up to 100Mbps ~ 1Gbps, can support a variety of mobile broadband data services.5G key competencies richer than previous generations of mobile communications, user experience, speed, density of connections, end to end delay, the peak rate and mobility and so will be the 5G key performance indicators. However, unlike the case in the past only to emphasize different peak rate, the industry generally believe that the rate of the user experience is the most important performance indicators, it truly reflects the real data rate available to the user, and the user experience is the closest performance. Based on the technology needs of the main scene 5G, 5G user experience rate should reach Gbps magnitude.Faced with diverse scenes of extreme performance demands differentiation, 5G cannot have solutions for all scenarios. In addition, the current wireless technology innovation has diversified development trend, in addition to the new multi -access technology, large -scale antenna array, ultra -dense network, the whole spectrum access, the new network architecture, also is considered to be the main technical direction.5G can play a key role in the major technology scene. [5]4. Challenges and SolutionsIn this part I outline some observed research challengesand directions in the mobile network development and show some may become the future trends and solutions that may lead to improved network performance while meeting the constantly increasing user demands. the new network architecture Gbps user exerperience rate Ultra -dense network Large -scale antenna array New multi -access technology The new network architecture Figure 1 - 5G Concept4.1 5G Transport ChallengeIn order to understand the 5G transport challenges one must understand how 5G may evolve the radio access segment.Among the various initiatives that are looking into 5G, we can defines 5G in terms of scenarios which the next generation wireless access networks will have to support. [6]A total of five future scenarios have been defined,namely amazingly fast (users want to enjoy instantaneous network connectivity), great service in a crowd, ubiquitous things communicating (i.e., effective support to Internet of Things), super real time and reliable connections, and best experience follows you. Each of these scenarios introduces a challenge .Three of these challenges (i.e., very high data rate, very dense crowds of users and mobility) are more traditional in the sense that they are related to continued enhancement of user experience and supporting increasing traffic volumes and mobility. Two emerging challenges, very low latency and very low energy, cost and massive number of devices, are associated with the application of wireless communications to new areas. Future applications may be associated with one or several of these scenarios imposing different challenges to the network. In METIS twelve specific test cases were defined and mapped onto the five scenarios. The selected test cases essentially sample the space of future applications. Once technical enablers that fulfill there quirements for these test cases are defined, it is expected that other applications subject to the same fundamental challenges, will successfully be supported. As a consequence, defining technical enablers for the 5G test cases means also defining technical solutions to the 5G challenges.While METIS[7] is focused on wireless access, the challenges defined for 5G are expected to impact also the transport. Support for very high data rates will require both higher capacity radio access nodes as well as a densification of radio access sites. This, in turn, translates into a transport network that needs to support more sites and higher capacity per site, i.e. huge traffic volumes. The great service in a crowd scenario will put requirements on the transport network to provide very high capacity on-demand to specific geographical locations. In addition, the best experience follows you scenario, suggests a challenge in terms of fast reconfigurability of the transport resources. On the contrary, the other 5G challenges are not expected to play as important role for shaping the transport, as for example the case of very low latency and very low energy, cost and massive number of devices. A properly dimensioned transport network based on modern wireless and/or optical technologies is already today able to provide extremely low latency, i.e., the end-to-end delay contribution of the transport network is usually almost negligible. In addition, while a huge number of connected machines and devices will create a challenge for the wireless network, it will most probably not significantly impact the transport. This is due to the fact that the traffic generated by a large number of devices over a geographical area will already be aggregated in the transport. The three scenarios for the transport network described above are summarized along with their corresponding challenges and test cases. Note that does not report all the original test cases but only those that pose challenges to the transport network. This information will be used later inthe paper to identify the appropriate transport technologies.4.2 5G Transport Challenge and some SolutionsThis section provides an overview of a number of transportoptions for 5G wireless networks. A 5G transport network can be divided in two different segments, i.e., small cell transportand metro/aggregation (Fig. 2). The small cell transport segment aggregates the traffic to/from the wireless small cells towards the metro/aggregation segment. Different solutions in terms of technology (e.g., optics, wireless) and topology (e.g., tree, ring, mesh) are possible depending on the specific wireless access scenario. The metro/aggregation segment, on the other hand, connects different site types (i.e., macro and/or small cells) among themselves and to the core network, the latter via the service edge (service node for the interconnection among different network domains).For the metro/aggregation segment one promising solution is represented by a dense-wavelength-division multiplexing (DWDM)[8] -centric network. In such a network, packet aggregation takes place at the edges of the network (e.g., at small/macro cells sites and at the service edge), while at center (i.e., between access and metro rings) switching is done completely in the optical domain thanks to active optical elements such as wavelength selective switches (WSSs) and reconfigurable optical add-drop multiplexers (ROADMs). It has already been demonstrated that DWDM-centric solutions have the potential to offer high capacity (in the order of tens to hundreds of Gbps) and lower energy consumption than their packet-centric counterparts (i.e., with packet aggregation at the center of the network). [9] For this reason the DWDM-centric metro/aggregation concept may represent a good candidate for future 5G transport networks.[10]4.3 Machine to Machine CommunicationMachine to Machine Communication Besides network evolution, we observe also device evolution that become more and more powerful. The future wireless landscape will serve not only mobile users through such devices as smartphones, tablets or game consoles but also a tremendous number of any other devices, such as cars, smart grid terminals, health monitoring devices and household appliances that would soon require a connection to the Internet. The number of connected devices will proliferate at a very high speed. It is estimated that the M2M traffic will increase 24-fold between 2012 and 2017 .[11]M2M communication is already today often used in fleet monitoring or vehicle tracking. Possible future usage scenarios include a wide variety of e-health applications and devices, for instance new electronic and wireless apparatus used to address the needs of elderly people suffering from diseases like Alzheimer’s, or wearable heart monitors. Suchsensors would enable patient monitoring and aid doctors to observe patients constantly and treat them in a better way. It will also reduce the costs of treatment, as it can be done remotely, without the need of going to a hospital.Remote patient monitoring using a Body Area Network (BAN), where a number of wireless sensors, both on-skin and implanted, record the patient’s health parameters and sends reports to a doctor, will soon become a reality and an important part of 5G paradigm. Therefore, in order to offer e-health services, 5G will need to provide high bandwidth, meet extremely high Quality of Service (QoS) requirements, e.g., ultra low latency and lossless video compression for medical purposes, and implement enhanced security mechanisms. Furthermore, extended work will need to be done to efficiently manage radio resources, due to high diversity of traffic types, ranging from the reports sent periodically by the meters, to high quality medical video transmission.4.3 Core Network VirtualisationMoving towards 5G imposes changes not only in the Radio Access Network (RAN) but also in the Core Network (CN), where new approaches to network design are needed to provide connectivity to growing number of users and devices. The trend is to decouple hardware from software and move the network functions towards the latter one. Software Defined Networking (SDN) being standardised by Open Networking Foundation (ONF) assumes separation of the control and data plane[12]. Consequently, thanks to centralization and programmability, configuration of forwarding can be greatly automated.Moreover, standardisation efforts aiming at defining Network Functions Virtualisation (NFV) are conducted by multiple industrial partners including network operators and equipment vendors within ETSI.[13] Introducing a new software based solution is much faster than installing an additional specialised device with a particular functionality. Both solutions would improve the network adaptability and make it easily scalable. As a result of simpler operation, one can expect more dynamic and faster deployment of new network features.4.4 SummaryI only list a partial of the challenges of 5G networks and possible solutions , in fact, before making a formal universal 5G are still many problems to be overcome, it also requires effort frontline researchers.5. 5G In China5.5.1 White paperFebruary 11, 2015,China released White paper about concept of 5G.It instantly make more people are concerned about 5G. People eager to 5G network as soon as possible. The White Paper published, the concept from various angles, core competencies, technical characteristics of 5G defined and interpreted. At the same time, this is the IMT-2020 (5G) to promote the group last year after the publication of the White Paper 5G vision and needs another masterpiece. The foreseeable future, as the Chinese government pay more attention to the development of 5G and adopt a more open attitude, with the joint efforts of the industry, and China will play an increasingly important role in the global 5G development, global industry will also be unified 5G standard stride forward.5.5.2 5G standardsChina will actively participate in the development of 5G standards, will help China to further enhance the patent position in international communication standards, escort for our mobile phone manufacturing.China is a big manufacturing country, the state has proposed the creation of a strategic shift to China, 3G and 4G standards successful experience will help us win more patents in the development of 5G standard time, to achieve the transformation of China to create the goal.5.5.3 China communications companiesFebruary 12, 2015, the International Telecommunication Union standard 5G start research work, and clearly the IMT-2020 work plan: will complete the IMT-2020 international standard preliminary studies in 2015, 2016 will be carried out 5G technical performance requirements and evaluation methods Research, by the end of 2017 to start collecting 5G candidate to complete standards by the end of 2020.It is worth noting that, in the 5G standards, Huawei, ZTE and other Chinese telecommunications companies such as Ericsson veteran communications companies also play an important role, in which Huawei from between 2013 to 2018, five years is ho throw $ 600 million 5G conduct research and innovation.Recently, ZTE 5G key technologies to achieve new progress. Following the end of the year to complete Massive MIMO antenna array massive field test, ZTE independently developed the proposed super dense network UDN, multiple users to share access to Multi-User Shared Access and other core technologies through demonstration, in Pre5G phase is expected to be applied.[14]Huawei CEO HuHouKun rotation, said in 2015, the company will spend the equivalent of about 10% in 2014 research and development budget, or $ 60 million, the development of 5G technology. Overall, the company's commitment in the next few years, $ 600 million investment in 5G technology. 5G is a next-generation mobile communications standard, is expected early in the next decade and put into use.[15]5.5.4 SummaryChina needs to have its own place in the 5G market, China's communications companies are also very hard, believe in the future, China's R & D level 5G will lead other countries.6. ConlusionIn this paper,I presented a summary of the concept,chanlleges,solusions and 5G in china.For 2020 and the future of the mobile Internet and networking business needs, 5G will focus on supporting the continuous wide area coverage, hot high-capacity, low power consumption and low latency connection highly reliable four main technical scenario, the use of large scale antenna array , ultra-dense networking, new multi-site, full-spectrum access and new network architectures, such as the core technology, through the evolution of new 4G air interface and two technical routes to achieve Gbps rate user experience, and to ensure consistency in service under a variety of scenarios .5G network to achieve real business there are a lot of unresolved issues. Also faced include how to design network architecture, including many technical challenges. Compared with previous generations of communications technology, 5G era biggest challenge is not how to increase the rate, but the user experience with traffic density, the number of terminals from a series of interwoven problems. As much as possible while also reducing user costs. This is the 5G network must be solved.5G study conducted in China are enthusiastic, China needs to accelerate the pace of its own 5G technology to get rid of dependence on foreign companies.5G study conducted in China are enthusiastic, China needs to accelerate the pace of its own 5G technology to get rid of dependence on foreign companies. 5G accelerate the development is conducive to China stand at the forefront of the competition in the next wave of data, a competitive advantage.7. Acronyms5G - Fifth-generation mobile communicationsSDN - software-defined networkingNFV - network functions virtualizationMEC - Mobile Edge computingFDMA - Frequency Division Multiple AccessTDMA - Time Division Multiple AccessCDMA - Code Division Multiple AccessOFDMA - Orthogonal Frequency Division Multiple AccessDWDM - dense-wavelength-division multiplexingBAN - Body Area NetworkQoS - Quality of ServiceRAN - Radio Access Network8. References[1]Chen Si ,Li Hua Sheng,”5G technology trends and challenges for radio management”, /news/41/a888991.html[2]”Samsung developed 5G technology”,/link?url=m_HOSi6QF36L7im-m0NRBaQggvikTgV0GLWBNy vN1OllSGp6_nYwU2B_fXsl6tEnyO0lXAw4Fnk0Ku0vtPSBMq#reference-[2]-764107 0-wrap[3] C114 China Communication Network,(Shanghai) ,March2015 ,”The EU announced 5G Vision: To guarantee the right to speak of global standards”/15/0311/10/AKE0JHMD000915BE.html[4]People’s Posts and Telecommunications News (PPTN),March,2015,”Bell Labs: 5G urgent task is to be completed as soon as possible standardization”/info/2015-03/11/c_134058306.htm[5] Baidu Encyclopedia,”5G network”/view/6220993.htm”[6] METIS deliverable D1.1, ”Scenarios, requirements and KPIs for 5G mobile and wireless system”, April 2013.[7] METIS deliverable D6.1, ”Simulation guidelines”, October 2013.[8] Shuqiang Zhang, Ming Xia, S. Dahlfort, ”Fiber routing, wavelength assignment and multiplexing for DWDM-centric converged metro/aggregation networks,” in Proc. of ECOC, Sept. 2013.[9] B. Skubic, I. Pappa, ”Energy consumption analysis of converged networks:Node consolidation vs metro simplification,” in Proc. of OFC,March 2013.[10] Matteo Fiorani,”Challenges for 5G Transport Networks”,IEEE,2014[11]Cisco, “Global Mobile Data Traffic Forecast Update,2012-2017,” Feb. 2013, White Paper.[12]Open Networking Foundation, “SDN Architecture Overview,” Dec. 2013.[13]ETSI, “Network Functions Virtualisation,” Oct. 2012, White Paper.[14]”ZTE 5G MUSA and UDN developed key technologies to achieve new progresss”/news/127/a892565.html[15]”Huawei will invest $ 600 million R & D 5G”/2015-04/02/content_543144.htm。
通信工程 毕业设计 外文文献翻译:超宽带系统的数据通信
英文资料Ultra-Wideband Systems for Data CommunicationsG. Racherla, J.L. Ellis, D.S. Furuno, S.C. LinGeneral Atomics, Advanced Wireless Group10240 Flanders Ct. San Diego CA 92121WebsitABSTRACTUltra-Widebandt (UWB) is a radio transmission scheme that uses extremely low power pulses of radio energy spread across a wide spectrum of frequencies. UWB has several advantages over conventional continuous wave radio communications including potential support for high data rates, robustness to multipath interference and fading. We present an overview of UWB technology and its use in data communications and networking. We look at design considerations for UWB based networks at various layers of the protocol stack.1.INTRODUCTIONUltra-Wideband [1-6]一also known as baseband or impulse radio一is a carrier-free radio transmission that uses narrow, extremely low power pulses of radio energy spread across a wide spectrum of frequencies. UWB has recently gained a great deal of interest due to the recent Federal Communications Commission (FCC) Report and Order which allocates the UWB band一7.5 GHz of unlicensed spectrum for indoor and outdoor communication applications. UWB communications are required to have a -10 dB fractional bandwidth of more than 20% or a -10 dB bandwidth of more than 500 MHz [7]. It is important to note that the FCC has not defined a specific modulation scheme to be used. UWB systems offer the promise of high data rate, low susceptibilityto multipath fading, high transmission security low prime power requirements, low cost, and simple design [1,2,5,6].UWB has been used in military applications for the past several years for ground-penetrating precision radar applications and secure communications [3,8]. For the past few years, UWB has been developed for commercial applications [1,2,5,6]. With the recent FCC [7] report and order for theuse of UWB technology, there has been an added impetus to this endeavor. Other notable UWB applications include collision avoidance radar, tagging/identification; geolocation [9] and data communications in personal area networks (PAN) and local area network (LAN) environments.There are several future challenges to the wide adoption of UWB for wireless data communications including the infancy of the technology in the commercial arena, lack of reliablechannel models, the early stages of standardization effort and lack of low-cost system on chip (SoC) implementations. In this paper, we look at UWB technology for data communications and inside a UWB physical (PHY) layer characteristics. We also briefly introduce other related wireless standards such as 802.11 [10], 802.15.3 [11-13] Bluetooth [14], HomeRF [15] and HIPERLAN [16] and present a brief synopsis of the regulatory effort worldwide with special emphasis on the FCC. We also present the design considerations for UWB based data networking.2.ULTRA-WIDEBAND TECHNOLOGYThe basic waveform that employed in a UWB system is an approximation to an impulse, such as that shown in Fig. 1. The short duration of the pulse is associated with large inherent bandwidth; hence, the nomenclature "Ultra-Wideband". Typical attributes of UWB waveforms are summarized in Table 1.Fig. 1. UWB waveform example.The high spectral content of the UWB waveform gives rise to one of the primary advantages UWB operation for communications where a UWB system is robust against multipath fading[17] and narrowband interference [18]. In multipath fading, where the transmitted radio frequency (rt) signal can reflect off objects in its transmission path and can cause destructive interferences at the receiver, a loss of reception can occur. ThisTable 1: Characteristics of Typical UWB SystemsFractional Bandwidth > 20%Pulse Width 0.1-2 asPulse Repetition Frequency 1 kHz-2 GHzAverage Transmitted Power<1mWeffect is particularly problematic indoors where there are many reflecting surfaces. In the frequency domain, multipath is shown as frequency selective fading. Because UWB communications systems spreads the transmitted data over a broad frequency band if destructive interference occurs at a specific frequency, whether due to multipath or narrowband interference, the information can still be recovered over the good frequencies.UWB implementations can provide low complexity, low cost solutions [19], thus enabling vast deployments of the technology. A critical component that reaffirms a low cost solution is noting that UWB signals, being carrier-less, have greater simplicity over narrowband transceivers and require smaller silicon die sizes [20]. UWB can be designed to achieve very high bit rates while still achieving low power consumption, a feature set which will be exploited by the consumer electronics industry [21]. UWB schemes can further be designed to be very scalable in terms of complexity, bit rate, power consumption, and range.UWB technology can support many applications. Different UWB modulation schemes offer different advantages for communication, radar, and precisiongeo-location applications. UWB technology, which operates between 3.1 and 10.6 GHz, intrinsically offers an efficient reuse of precious spectrum by operating stealthily at the noise floor [22]. This UWB system operates at low power, to be compliant with operating under FCC Part 15 emissions, across a wide range of frequencies. As a spread spectrum technology, UWB offers a low probability of intercept and a low probability of detection [8]. Thus, it is particularly well suited for covert military or sensitive usage seenarios [8]. Because UWB signals have extremely short bursts in time (e.g., durations of 1 ns or less) they are suited for precision geo-location applications. Though UWB intrinsically offers the above-mentioned features, application optimization and improvements on these characteristics are left to specific designs and implementations, most notably by careful consideration of modulation schemes.2.1. UWB System Design ConsiderationsSeveral considerations are needed when designing a PAN. First, low power design is necessary because the portable devices within the network are battery powered. Second, high data rate transmission is crucial for broadcasting multiple digi\tal audio and video streams: Lastly, low cost is a prerequisite to broadening consumer adoption. In addition to these criteria, the UWB system designer must address synchronization and coexistence. Capturing and locking onto these short pulses make synchronization a non-trivial task. Coexisting peacefully with other wireless systems without interference is important;In particular, one needs to pay attention to the 802.1 la wireless LANs that operate in the 5 GHz ISM bands.At the physical layer, additional challenges lie in the transceiver and antenna design. At the transmitter, pulse shaping is required to produce flat and wideband emission in the desired frequency bands. Although new integrated circuits provide less expensive forms of integration, the pulses can be affected by the parasitics from the component and packaging [23]. To accommodate the high data rates, tradeoffs between high and low pulse repetition frequency (PRF) and modulation schemes must be considered. The low PRF system with higher modulation (more bits per symbol) may require a more complex receiver, while the high PRF system with lower modulation may lead to performance degradation for delay spread in the channel. Finally, traditional antenna designs gear towards narrow band systems. To avoid dispersion at the receiver, the new wideband antennas need phase linearity and a fixed phase center [23].3. UWB STANDARDIZATION ANDREGULATORY EFFORTSThere are several standards bodies presently considering, at some level, UWB technologies. The standards body most advanced in the consideration of UWB is study group "a" of IEEE 802.15.3, which was formed in November 2001 [11-13]. A serious effort is well underway to define a UWB channel model, and numerous UWB tutorials have been given. Many hallway conversations talk to a physical layer standard being ratified in 2004 (though there is no formal knowledge or position on this) and will accompany the soon to be approved 802.15.3 Medium Access Control (MAC) which supports quality of service (QoS) for real-time multimedia applications [12]. The technical requirements presently call for bit rates of 110 to 200 Mbps at ranges up to 10 m, with the option to achieve 480 Mbps possibly at shorter distances. The powerconsumption requirement is presently set at 100 to 250 mW with lOe 5 bit error rate at the top of the physical layer. Complexity/cost are presently expected to be comparable to Bluetooth and the physical layer is required to support four collocated piconets. Coexistence is presently crucial (e.g., IEEE 802.1 la) and the ability to scale the technology is key to a long lasting and widely adopted standard. These technical requirements come from documents that are still being revised; additionally, it is not possible to predict if proposals may fall short of meeting some of the desired requirements.The United States FCC issued a report and order in the early part of 2002. This landmark decision to permit UWB operation in the 3.1 to 10.6 GHz spectrum under Part 15 emis- sion limits, with some additional restrictions, has catalyzed development and standardization processes as is evident by the sheer number of entities (companies, academic and government institutions) associated with UWB and through the serious efforts of the IEEE 802.15.3 group. The FCC carefully chose the frequency band of operation to be above 3.1 GHz to avoid interfering with GPS and other life critical systems. Furthermore, the FCC ruled that emissions below Part 15 would pro-vide for peaceful coexistence, the ability to have narrowband and UWB systems collocated on a non-interfering basis, because unintentional emissions from devicessuch as laptops are also limited to Part 15 rules. This ruling makes it possible to have up to 15 UWB frequency bands in the 7.5 GHz allocated unlicensed spectrum [7]. Extensive efforts are being conducted throughout Europe (CEPT, ETSI, and the European Commission), Korea, and Japan (Association of Radio Industries and Businesses, and the Japanese Ministry of Telecommunications).4. NETWORKING WITH UWB SYSTEMSThere is a significant interest in the ability to perform location determination and tracking of assets and people throughout warehouses, factories, ships, hospita梦,business environments, and other buildings or structures. The ability for UWB technologies to operate within such intense multipath environments in conjunction with the ability for UWB to provide very accurate geo-location capability at low cost and long battery life justifies the increasing technological activity in this market [20].As the rf tags [24] are distributed, it is also recognized tha they can be coordinated and networked. To further reduce the cost of the transceivers, position determination can occur at networked computer terminals. Additionally, it is quite conceivable that tag complexity can be further simplified by installink transmitters that chirp periodically [8]. Just as UWB demonstrates many benefits for rf tags, the technology equally lends itself to distributed sensor networks [9]. Sensor network applications include feedback controls systems and environmental surveillance for commercial, industrial,_ and military applications.In the data communication area, UWB technology may be used to implement ad-hoc networks. An ad-hoc network [25-27] is characterized by a collection of hosts that form a network "on-the-fly". An ad-hoc network is a multi-hop wireless network wherein each host also acts as a router. Mobile TRANSPORT Ad-hoc NETworks (MANETs) [25-27] are ad-hoc networks wherein the wireless hosts have the ability to move. Mobility of hosts in MANETs has a profound impact on the topology of the network and its performance. Figure 2 illustrates how the various layers of the OSI protocol stack have to operate in order to successfully complete a communication session. We look at some of relevant design issues at the different layers for UWB-based sensor networks and MANETs.4.1. Design Issues for Layers of the Protocol StackThere are several design considerations of sensor networks setup (including rftags) [24]. The sensors typically work on batteries and need be low cost, low power, with LPI/LPD and the ability to do geo-location. All of these requirements are satisfied by a UWB PHY.The PHY layer [26,27] is a very complex layer which deals with the medium specification (physical, electrical and mechanical) for data transmission between devices. The PHY layer specifies the operating frequency range, the operating temperature range, modulation scheme, channelization scheme. channel switch time, timing, synchronization, symbol coding, and interference from other systems, carrier-sensing and transmit/receive operations of symbols and power requirements for operations. The PHY layer interacts closely with, the MAC sublayer to ensure smooth performance of the network. The PHY layer for wireless systems (such as MANETs) has special considerations to take into account as the wireless medium is inherently error-prone and prone to interference from other wireless and rf systems in the proximity. Multipath is important to consider when designing wireless PHY layer as the rf propagation environment changes dynamically with time; frequent disconnections may occur. The problem is exacerbated when the devices in the network are mobile because of handoffs and new route establishment. It should be noted that there is a concerted effort by several UWB companies muster supportfor a UWB-based high data rate PITY in the IEEE 802.15.3 working group.The data link layer consists of the Logical Link Control (LLC) and the MAC sub layers. The MAC sublayer is responsible for channel access and the LLC is responsible for link maintenance, framing data unit, synchronization, error detection and possible recovery, and flow control. The MAC sublayer tries to gain access to the shared channel to prevent collision and distortion of transmitted frames with frames sent by the MAC sublayers of other nodes sharing the medium. TheMAC sublayer in sensor networks and MANETs needs to be power-aware, self-organizing and support mobility and handoffs.The network layer of such networks should perform routing so as to minimize power and the number of node hops in the route. In some cases, flooding/gossiping may be required to increase chances of the packets reaching the destination. Data aggregation/fusion may be used for. data-centric routing [24] in the network layer. The network layer needs to allow for route maintenance and updates for fast changing network topology.The transport layer is responsible for the end-to-end integrity of data in thenetwork. The transport layer performs multiplexing, segmenting, blocking, concatenating, error detection and recovery, flow control and expedited data transfer. In the MANET environment, the mobility of the nodes will almost certainly cause packets to be delivered out of order and a significant delay in the acknowledgements is to be expected as a result. Retransmissions are very expensive in terms of the power requirements. Transport protocols for MANETs and sensor networks need to focus on the development of feedback mechanisms that enable the transport layer to recognize the dynamics of the network and adjust its retransmission timer, window size and perform congestion control with more information on the network.Fig. 2. Issues at each layer of the protocol stackThe application layer needs support for location-based services, network management, task assignment, query and data dissemination for sensor networks and possible MANETs.5. RELATED TECHNOLOGIESIn order to better understand UWB-based technologies, we look at some related technology standards. More information on these technologies can be found in Ref. 27.5.1. BluetoothBluetooth [14] is a short-range radio technology standard originallyintended as a wireless cable replacement to connect portable computers, wireless devices, handsets and headsets. Bluetooth devices operate in the 2.4 GHz ISM band. Bluetooth uses the concept of a piconet which is a MANET with a master device controlling one or several slave devices. Bluetooth also allow scatternets wherein a slave device can be part of multiple piconets. Bluetooth has beed designed to handle both voice and data. traffic.5.2. HIPERIANl1 and HIPERIANIlHIPERLAN/I and HIPERLAN/2 [16] are European wireless LAN (WLAN) standards developed by European Telecommunications Standards Institute (ETSI). HIPERLAN/1 is a wireless equivalent of Ethernet while HIPERLAN/2 has architecture based on wireless Asynchronous Transfer Mode (ATM). Both the standards use dedicated frequency spectrum at -5 GHz. HIPERLAN/I provides a gross data rate of 23.5 Mb/s and net data rate of more than 18 Mb/s while HIPERLAN/2 provides gross data rates of 6/16/36154 Mb/s and a maximum of 50 Mb/s net data rate. Both standards use 10/100/1000 mW of transmit power and have a maximum range of 50 m. Also, the standards provide isochronous and asynchronous services with support for QoS. However, they have different channel a-ss and modulation schemes.5.3. IEEE 802]]This IEEE family of wireless Etherdet standards is primarily intended for indoor and in-building WLANs. There are several varities of this standard. The current available versions are the 802.1 la, 802.11b and 802.llg (emerging draft standard) with other versions which are starting to show on the horizon [10]. The 802.11 standards support ad-hoc networking as well as connections using an access point (AP). The standard provides specifications of the PHY and the MAC layers. The MAC specified uses CSMA/CA for access and provides service discovery and scanning, link setup and tear down, data fragmentation, security, power management and roaming facilities. The 802.1 la PHY is similar to the HIPERLAN/2 PHY. The PHY uses OFDM and operates in the 5 GHz UNII band. 802.1 la supports data rates ranging from 6 to 54 Mbps. 802.11 a currently offers much less potential for rf interference than other PHYs (e.g., 802.11b and 802.11g) that utilize the crowded 2.4 GHz ISM band. 802.11 a can support multimedia applications in densely populated user environments.' The 802.11b standard, proposed jointly by Harris and Lucent Technologies, extends the 802.11 Direct Sequence Spread Spectrum (DSSS) PHY to provide 5.5 and 11 Mb/s data rates.5.4. IEEE 802.75.3The emerging draft standard [11-13] defines MAC and PHY (2.4 GHz) layer specifications for a Wireless Personal Area Network (WPAN). The standard is based on the concept of a piconet which is a network confined to a 10 m personal operating space (POS) around a person or object. A WPAN consists of one or more collocated piconets. Each piconet is controlled by a piconet coordinator (PNC) and may consist of devices (DEVs). The 802.15.3 PHY is defined for 2.4 to 2.4835 GHz band and has two defined channel plans. It supports five different data rates (11 to 55 Mb/s). The base uncoded PHY rate is 22 Mb/s5.5. HomeRFHomeRF [15] working group was formed to develop a standard for wireless data communication between personal computers and consumer electronics in a home environment. The HomeRF standard is technically solid, simple, secure, and is easy to use. HomeRF networks provide a range of up to 150 ft typically enough for home networking. HomeRF uses Shared Wireless Access Protocol (SWAP) to provide efficient delivery of voice and data traffic. SWAP uses a transmit power of up to 100 mW and a gross data rate of 2 Mb/s. It can support a maximum of 127 devices per network. A SWAP-based system can work as an ad-hoc network or as a managed network using a connection point6. CONCLUSIONIn this paper, we presented an overview of UWB technology and its characteristics and advantages over conventional, continuous wave transmissions. We presented how UWB is well suited for several applications like sensor networks and MANETs. UWB technology has garnered a lot of interest among vendors who are looking at standardizing the use of the technology in various forums including IEEE.中文翻译超宽带系统的数据通信G. Racherla, J.L. Ellis, D.S. Furuno, S.C. LinGeneral Atomics, Advanced Wireless Group10240 Flanders Ct.San Diego CA 92121E-mail: {gopal.racherla, jason.ellis, susan.lin,超宽带(UWB)是一种在宽频谱范围内使用超低功耗传播无线脉冲能量的无线电传输方案。
5G无线通信基础英文论文 A Brief Introduction About 5G Network
A Brief Introduction About 5G Network JiaAbstractWith the rapid development of wireless technologies, theconcept of the Fifth Generation (5G) wireless communication system started to emerge. But most people know little about 5G,including some aspects of 5G wireless communication networks ,just like what 5G is about: what are the building blocks of core 5G system concept, what are the main challenges and how to tackle them. Besides,A number of countries and organizations working on 5G, 5G development situation in China is of concern to everyone, China also needs to have its own place in such a competitive environment. Keywords:5G Network, history,Core concept, Challenges, Solutions, In chinaTable of Content1. Introduction................................................................................................................. - 3 -2. Research and development history ............................................................................. - 3 -3. Core Concept .............................................................................................................. - 4 -4. Challenges and Solutions............................................................................................ - 5 - 4.1 5G Transport Challenge ........................................................................................ - 6 - 4.2 5G Transport Challenge and some Solutions........................................................ - 7 - 4.3 Machine to Machine Communication................................................................... - 7 - 4.3 Core Network Virtualisation ................................................................................. - 8 -4.4 Summary............................................................................................................... - 8 -5. 5G In China................................................................................................................. - 9 - 5.5.1 White paper........................................................................................................ - 9 - 5.5.2 5G standards ...................................................................................................... - 9 - 5.5.3 China communications companies .................................................................... - 9 -5.5.4 Summary.......................................................................................................... - 10 -6. Conlusion.................................................................................................................. - 10 -7. Acronyms.................................................................................................................. - 11 -8. References................................................................................................................. - 11 -1. Introduction5G (Fifth-generation mobile communications) is a new generation of mobile communication mobile communication systems for 2020, with high spectral efficiency and low power consumption, in terms of transfer rate and resource utilization improvement over 4G system 10 times, its wireless coverage performance and user experience will be significantly improved. 5G will be closely integrated with other wireless mobile communication technology, constitute a new generation of ubiquitous mobile information network, to meet future mobile Internet traffic 1000x development needs in 10 years.[1]In this paper I will show you some latest research and development history,what are the building blocks of core 5G system concept, what are the main challenges and how to tackle them firstly. In the rest of paper I will show how 5G development in China in recent years and my conclusion after research literature.2. Research and development historyFebruary 2013, the EU announced that it would grant 50 million euros to accelerate the development of 5G mobile technology, plans to launch a mature standard in 2020. [2][3]May 13,2013,South Korea's Samsung Electronics Co., Ltd. announced that it has successfully developed the 5th generation mobile communication (5G) core technology, which is expected to begin in 2020 to commercialization. The technology can transmit data at ultra-high frequency 28GHz to 1Gbps per second speed, and the maximum transmission distance of up to 2 km. In contrast, the current fourth generation Long Term Evolution (4GLTE) and services of only the transmission rate 75Mbps. Prior to the transmission bottleneck is widely believed that a technical problem, while Samsung Electronics is the use of 64 adaptive array antenna elements transmission technology to crack this problem. Compared with the transmission speed of 4G technology in South Korea, 5G technology is hundreds of times faster. Using this technique, download a high-definition (HD) movie just need 10 seconds.Back in 2009, Huawei has launched the early research related technologies, and to show the prototype of the 5G base in later years.In November 6, 2013,Huawei announced that it would invest $600 million in 2018 for the 5G technology development and innovation, and predicted that users will enjoy 20Gbps commercial 5G mobile networks in 2020. May 8, 2014, the Japanese telecom operator NTT DoCoMo announced officially, Ericsson ,Nokia, Samsung and other six manufacturers to work together, began testing override 1000 times than existing 4G networks the carrying capacity of the high-speed network 5G network, the transmission speed is expected to 10Gbps. Outdoor testing scheduled to commence in 2015, and expects to begin operations in 2020.[3]March 1, 2015, the British "Daily Mail" reported that the British 5G network has successfully developed and tested for data transmission within 100 meters per second data transfer of up to 125GB, is 6.5 times the 4G network, in theory, a 30 seconds to download movies, adding that investment in public test in 2018, 2020 officially put into commercial use.[4]February 11, 2015 in the afternoon news, IMT-2020 (5G) to promote the group (hereinafter referred to as "advance group") held a conference in Beijing 5G concept of white paper. White Paper from the mobile Internet and networking composed mainly of application scenarios, business needs and challenges of starting summed continuous wide area coverage, high reliability of the four major technology 5G scene of high capacity, low power consumption and low latency connection. Meanwhile, the combination of core technologies and key capabilities 5G and 5G concept proposed by the "flag sexuality index + a set of key technologies" common definition.March 3,2015,the European Economic and Social Commission for Digital Furusawa Ottinge officially announced the EU's vision of public-private partnerships 5G, and strive to ensure that the right to speak in the next generation of mobile technology in Europe in the global standard.Ottinger said that, 5G vision of public-private partnership involves not only fiber, wireless or satellite communications network integrated with each other, will also use the software-defined networking (SDN), network functions virtualization (NFV), Mobile Edge computing (MEC) and Fog Computing technology. In the spectrum, the EU's vision of public-private partnership will be designated 5G hundreds of megahertz to improve network performance, 60 GHz and higher frequency bands will also be taken into account.A number of countries and organizations announced, 5G network will be operational between 2020 ~ 2025.3. Core ConceptWhat is 5G? I believe many people will be so questionable when see 5G. Judging from the word meaning, 5G refers to the fifth generation of mobile communications. However, how should it define? Currently, the global industry for 5G concept not yet agreed. China IMT-2020 (5G) group released the White Paper considers the concept 5G, 5G integrated key capabilities and core technology, 5G concept by "important targets" and "a group of key technologies" to a common definition. Among them, the flag indicators "Gbps rate user experience" is a set of key technologies, including large-scale antenna array, ultra-dense networking, new multi-site, full-spectrum access and new network architectures.Recalling the course of development of mobile communications, each generation ofmobile communication systems can be defined by sexual performance indicators and signs of key technologies. Wherein, 1G using FDMA, only analog voice services; 2G mainly using TDMA, can provide voice and low -speed digital data services; 3G to CDMA technology is characterized by user peak rate of 2Mbps to reach tens of Mbps, support multimedia data services; 4G OFDMA technology as the core, the user peak rate of up to 100Mbps ~ 1Gbps, can support a variety of mobile broadband data services.5G key competencies richer than previous generations of mobile communications, user experience, speed, density of connections, end to end delay, the peak rate and mobility and so will be the 5G key performance indicators. However, unlike the case in the past only to emphasize different peak rate, the industry generally believe that the rate of the user experience is the most important performance indicators, it truly reflects the real data rate available to the user, and the user experience is the closest performance. Based on the technology needs of the main scene 5G, 5G user experience rate should reach Gbps magnitude.Faced with diverse scenes of extreme performance demands differentiation, 5G cannot have solutions for all scenarios. In addition, the current wireless technology innovation has diversified development trend, in addition to the new multi -access technology, large -scale antenna array, ultra -dense network, the whole spectrum access, the new network architecture, also is considered to be the main technical direction.5G can play a key role in the major technology scene. [5]4. Challenges and SolutionsIn this part I outline some observed research challengesand directions in the mobile network development and show some may become the future trends and solutions that may lead to improved network performance while meeting the constantly increasing user demands. the new network architecture Gbps user exerperience rate Ultra -dense network Large -scale antenna array New multi -access technology The new network architecture Figure 1 - 5G Concept4.1 5G Transport ChallengeIn order to understand the 5G transport challenges one must understand how 5G may evolve the radio access segment.Among the various initiatives that are looking into 5G, we can defines 5G in terms of scenarios which the next generation wireless access networks will have to support. [6]A total of five future scenarios have been defined,namely amazingly fast (users want to enjoy instantaneous network connectivity), great service in a crowd, ubiquitous things communicating (i.e., effective support to Internet of Things), super real time and reliable connections, and best experience follows you. Each of these scenarios introduces a challenge .Three of these challenges (i.e., very high data rate, very dense crowds of users and mobility) are more traditional in the sense that they are related to continued enhancement of user experience and supporting increasing traffic volumes and mobility. Two emerging challenges, very low latency and very low energy, cost and massive number of devices, are associated with the application of wireless communications to new areas. Future applications may be associated with one or several of these scenarios imposing different challenges to the network. In METIS twelve specific test cases were defined and mapped onto the five scenarios. The selected test cases essentially sample the space of future applications. Once technical enablers that fulfill there quirements for these test cases are defined, it is expected that other applications subject to the same fundamental challenges, will successfully be supported. As a consequence, defining technical enablers for the 5G test cases means also defining technical solutions to the 5G challenges.While METIS[7] is focused on wireless access, the challenges defined for 5G are expected to impact also the transport. Support for very high data rates will require both higher capacity radio access nodes as well as a densification of radio access sites. This, in turn, translates into a transport network that needs to support more sites and higher capacity per site, i.e. huge traffic volumes. The great service in a crowd scenario will put requirements on the transport network to provide very high capacity on-demand to specific geographical locations. In addition, the best experience follows you scenario, suggests a challenge in terms of fast reconfigurability of the transport resources. On the contrary, the other 5G challenges are not expected to play as important role for shaping the transport, as for example the case of very low latency and very low energy, cost and massive number of devices. A properly dimensioned transport network based on modern wireless and/or optical technologies is already today able to provide extremely low latency, i.e., the end-to-end delay contribution of the transport network is usually almost negligible. In addition, while a huge number of connected machines and devices will create a challenge for the wireless network, it will most probably not significantly impact the transport. This is due to the fact that the traffic generated by a large number of devices over a geographical area will already be aggregated in the transport. The three scenarios for the transport network described above are summarized along with their corresponding challenges and test cases. Note that does not report all the original test cases but only those that pose challenges to the transport network. This information will be used later inthe paper to identify the appropriate transport technologies.4.2 5G Transport Challenge and some SolutionsThis section provides an overview of a number of transportoptions for 5G wireless networks. A 5G transport network can be divided in two different segments, i.e., small cell transportand metro/aggregation (Fig. 2). The small cell transport segment aggregates the traffic to/from the wireless small cells towards the metro/aggregation segment. Different solutions in terms of technology (e.g., optics, wireless) and topology (e.g., tree, ring, mesh) are possible depending on the specific wireless access scenario. The metro/aggregation segment, on the other hand, connects different site types (i.e., macro and/or small cells) among themselves and to the core network, the latter via the service edge (service node for the interconnection among different network domains).For the metro/aggregation segment one promising solution is represented by a dense-wavelength-division multiplexing (DWDM)[8] -centric network. In such a network, packet aggregation takes place at the edges of the network (e.g., at small/macro cells sites and at the service edge), while at center (i.e., between access and metro rings) switching is done completely in the optical domain thanks to active optical elements such as wavelength selective switches (WSSs) and reconfigurable optical add-drop multiplexers (ROADMs). It has already been demonstrated that DWDM-centric solutions have the potential to offer high capacity (in the order of tens to hundreds of Gbps) and lower energy consumption than their packet-centric counterparts (i.e., with packet aggregation at the center of the network). [9] For this reason the DWDM-centric metro/aggregation concept may represent a good candidate for future 5G transport networks.[10]4.3 Machine to Machine CommunicationMachine to Machine Communication Besides network evolution, we observe also device evolution that become more and more powerful. The future wireless landscape will serve not only mobile users through such devices as smartphones, tablets or game consoles but also a tremendous number of any other devices, such as cars, smart grid terminals, health monitoring devices and household appliances that would soon require a connection to the Internet. The number of connected devices will proliferate at a very high speed. It is estimated that the M2M traffic will increase 24-fold between 2012 and 2017 .[11]M2M communication is already today often used in fleet monitoring or vehicle tracking. Possible future usage scenarios include a wide variety of e-health applications and devices, for instance new electronic and wireless apparatus used to address the needs of elderly people suffering from diseases like Alzheimer’s, or wearable heart monitors. Suchsensors would enable patient monitoring and aid doctors to observe patients constantly and treat them in a better way. It will also reduce the costs of treatment, as it can be done remotely, without the need of going to a hospital.Remote patient monitoring using a Body Area Network (BAN), where a number of wireless sensors, both on-skin and implanted, record the patient’s health parameters and sends reports to a doctor, will soon become a reality and an important part of 5G paradigm. Therefore, in order to offer e-health services, 5G will need to provide high bandwidth, meet extremely high Quality of Service (QoS) requirements, e.g., ultra low latency and lossless video compression for medical purposes, and implement enhanced security mechanisms. Furthermore, extended work will need to be done to efficiently manage radio resources, due to high diversity of traffic types, ranging from the reports sent periodically by the meters, to high quality medical video transmission.4.3 Core Network VirtualisationMoving towards 5G imposes changes not only in the Radio Access Network (RAN) but also in the Core Network (CN), where new approaches to network design are needed to provide connectivity to growing number of users and devices. The trend is to decouple hardware from software and move the network functions towards the latter one. Software Defined Networking (SDN) being standardised by Open Networking Foundation (ONF) assumes separation of the control and data plane[12]. Consequently, thanks to centralization and programmability, configuration of forwarding can be greatly automated.Moreover, standardisation efforts aiming at defining Network Functions Virtualisation (NFV) are conducted by multiple industrial partners including network operators and equipment vendors within ETSI.[13] Introducing a new software based solution is much faster than installing an additional specialised device with a particular functionality. Both solutions would improve the network adaptability and make it easily scalable. As a result of simpler operation, one can expect more dynamic and faster deployment of new network features.4.4 SummaryI only list a partial of the challenges of 5G networks and possible solutions , in fact, before making a formal universal 5G are still many problems to be overcome, it also requires effort frontline researchers.5. 5G In China5.5.1 White paperFebruary 11, 2015,China released White paper about concept of 5G.It instantly make more people are concerned about 5G. People eager to 5G network as soon as possible. The White Paper published, the concept from various angles, core competencies, technical characteristics of 5G defined and interpreted. At the same time, this is the IMT-2020 (5G) to promote the group last year after the publication of the White Paper 5G vision and needs another masterpiece. The foreseeable future, as the Chinese government pay more attention to the development of 5G and adopt a more open attitude, with the joint efforts of the industry, and China will play an increasingly important role in the global 5G development, global industry will also be unified 5G standard stride forward.5.5.2 5G standardsChina will actively participate in the development of 5G standards, will help China to further enhance the patent position in international communication standards, escort for our mobile phone manufacturing.China is a big manufacturing country, the state has proposed the creation of a strategic shift to China, 3G and 4G standards successful experience will help us win more patents in the development of 5G standard time, to achieve the transformation of China to create the goal.5.5.3 China communications companiesFebruary 12, 2015, the International Telecommunication Union standard 5G start research work, and clearly the IMT-2020 work plan: will complete the IMT-2020 international standard preliminary studies in 2015, 2016 will be carried out 5G technical performance requirements and evaluation methods Research, by the end of 2017 to start collecting 5G candidate to complete standards by the end of 2020.It is worth noting that, in the 5G standards, Huawei, ZTE and other Chinese telecommunications companies such as Ericsson veteran communications companies also play an important role, in which Huawei from between 2013 to 2018, five years is ho throw $ 600 million 5G conduct research and innovation.Recently, ZTE 5G key technologies to achieve new progress. Following the end of the year to complete Massive MIMO antenna array massive field test, ZTE independently developed the proposed super dense network UDN, multiple users to share access to Multi-User Shared Access and other core technologies through demonstration, in Pre5G phase is expected to be applied.[14]Huawei CEO HuHouKun rotation, said in 2015, the company will spend the equivalent of about 10% in 2014 research and development budget, or $ 60 million, the development of 5G technology. Overall, the company's commitment in the next few years, $ 600 million investment in 5G technology. 5G is a next-generation mobile communications standard, is expected early in the next decade and put into use.[15]5.5.4 SummaryChina needs to have its own place in the 5G market, China's communications companies are also very hard, believe in the future, China's R & D level 5G will lead other countries.6. ConlusionIn this paper,I presented a summary of the concept,chanlleges,solusions and 5G in china.For 2020 and the future of the mobile Internet and networking business needs, 5G will focus on supporting the continuous wide area coverage, hot high-capacity, low power consumption and low latency connection highly reliable four main technical scenario, the use of large scale antenna array , ultra-dense networking, new multi-site, full-spectrum access and new network architectures, such as the core technology, through the evolution of new 4G air interface and two technical routes to achieve Gbps rate user experience, and to ensure consistency in service under a variety of scenarios .5G network to achieve real business there are a lot of unresolved issues. Also faced include how to design network architecture, including many technical challenges. Compared with previous generations of communications technology, 5G era biggest challenge is not how to increase the rate, but the user experience with traffic density, the number of terminals from a series of interwoven problems. As much as possible while also reducing user costs. This is the 5G network must be solved.5G study conducted in China are enthusiastic, China needs to accelerate the pace of its own 5G technology to get rid of dependence on foreign companies.5G study conducted in China are enthusiastic, China needs to accelerate the pace of its own 5G technology to get rid of dependence on foreign companies. 5G accelerate the development is conducive to China stand at the forefront of the competition in the next wave of data, a competitive advantage.7. Acronyms5G - Fifth-generation mobile communicationsSDN - software-defined networkingNFV - network functions virtualizationMEC - Mobile Edge computingFDMA - Frequency Division Multiple AccessTDMA - Time Division Multiple AccessCDMA - Code Division Multiple AccessOFDMA - Orthogonal Frequency Division Multiple AccessDWDM - dense-wavelength-division multiplexingBAN - Body Area NetworkQoS - Quality of ServiceRAN - Radio Access Network8. References[1]Chen Si ,Li Hua Sheng,”5G technology trends and challenges for radio management”, /news/41/a888991.html[2]”Samsung developed 5G technology”,/link?url=m_HOSi6QF36L7im-m0NRBaQggvikTgV0GLWBNy vN1OllSGp6_nYwU2B_fXsl6tEnyO0lXAw4Fnk0Ku0vtPSBMq#reference-[2]-764107 0-wrap[3] C114 China Communication Network,(Shanghai) ,March2015 ,”The EU announced 5G Vision: To guarantee the right to speak of global standards”/15/0311/10/AKE0JHMD000915BE.html[4]People’s Posts and Telecommunications News (PPTN),March,2015,”Bell Labs: 5G urgent task is to be completed as soon as possible standardization”/info/2015-03/11/c_134058306.htm[5] Baidu Encyclopedia,”5G network”/view/6220993.htm”[6] METIS deliverable D1.1, ”Scenarios, requirements and KPIs for 5G mobile and wireless system”, April 2013.[7] METIS deliverable D6.1, ”Simulation guidelines”, October 2013.[8] Shuqiang Zhang, Ming Xia, S. Dahlfort, ”Fiber routing, wavelength assignment and multiplexing for DWDM-centric converged metro/aggregation networks,” in Proc. of ECOC, Sept. 2013.[9] B. Skubic, I. Pappa, ”Energy consumption analysis of converged networks:Node consolidation vs metro simplification,” in Proc. of OFC,March 2013.[10] Matteo Fiorani,”Challenges for 5G Transport Networks”,IEEE,2014[11]Cisco, “Global Mobile Data Traffic Forecast Update,2012-2017,” Feb. 2013, White Paper.[12]Open Networking Foundation, “SDN Architecture Overview,” Dec. 2013.[13]ETSI, “Network Functions Virtualisation,” Oct. 2012, White Paper.[14]”ZTE 5G MUSA and UDN developed key technologies to achieve new progresss”/news/127/a892565.html[15]”Huawei will invest $ 600 million R & D 5G”/2015-04/02/content_543144.htm。
通信工程移动通信中英文对照外文翻译文献
中英文翻译(文档含英文原文和中文翻译)附件1:外文资料翻译译文通用移动通信系统的回顾1.1 UMTS网络架构欧洲/日本的3G标准,被称为UMTS。
UMTS是一个在IMT-2000保护伞下的ITU-T 批准的许多标准之一。
随着美国的CDMA2000标准的发展,它是目前占主导地位的标准,特别是运营商将cdmaOne部署为他们的2G技术。
在写这本书时,日本是在3G 网络部署方面最先进的。
三名现任运营商已经实施了三个不同的技术:J - PHONE 使用UMTS,KDDI拥有CDMA2000网络,最大的运营商NTT DoCoMo正在使用品牌的FOMA(自由多媒体接入)系统。
FOMA是基于原来的UMTS协议,而且更加的协调和标准化。
UMTS标准被定义为一个通过通用分组无线系统(GPRS)和全球演进的增强数据技术(EDGE)从第二代GSM标准到UNTS的迁移,如图。
这是一个广泛应用的基本原理,因为自2003年4月起,全球有超过847万GSM用户,占全球的移动用户数字的68%。
重点是在保持尽可能多的GSM网络与新系统的操作。
我们现在在第三代(3G)的发展道路上,其中网络将支持所有类型的流量:语音,视频和数据,我们应该看到一个最终的爆炸在移动设备上的可用服务。
此驱动技术是IP协议。
现在,许多移动运营商在简称为2.5G的位置,伴随GPRS的部署,即将IP骨干网引入到移动核心网。
在下图中,图2显示了一个在GPRS网络中的关键部件的概述,以及它是如何适应现有的GSM基础设施。
SGSN和GGSN之间的接口被称为Gn接口和使用GPRS隧道协议(GTP的,稍后讨论)。
引进这种基础设施的首要原因是提供连接到外部分组网络如,Internet或企业Intranet。
这使IP协议作为SGSN和GGSN之间的运输工具应用到网络。
这使得数据服务,如移动设备上的电子邮件或浏览网页,用户被起诉基于数据流量,而不是时间连接基础上的数据量。
通信毕设中英文文献翻译
英文文献The Application of one point Multiple Access Spread SpectrumCommunication SystemLiu Jiangang, Nan yang City, Henan Province Electric Power Industry Bureau【ABSTRACT】Spread Spectrum Digital Microwave communication as a communication, because their excellent performance have been widely used. The article in Nan yang City Power Industry Bureau one point Multiple Access Spread Spectrum Communication System as an example. briefed the spread spectrum communications, the basic concept and characteristics of the power system communication applications.KEYWORDS:one point multiple access; Spread-spectrum communication; AttenuationNan yang City in the outskirts of Central cloth 35 to 11 kv substation farm terminals, their operation management rights belong to the Council East, Rural Power Company west (the eastern suburb of agricultural management companies -- four, the western suburbs of Rural Power Company Management 7), Scheduling of the various stations of the means of communication to the original M-150 radio and telephone posts. 2002 With the transformation of rural network, the remote station equipment into operation and communication channels to put a higher demand .As PUC Dispatch Communication Building to the east and west of farmers -- the difference between a company linked to fiber, Therefore, if 11 substations and the establishment of a transfer Link Building links Point may be the data and voice were sent to two rural power companies dispatch room, Rural Network scheduling for the implementation of automation to create the necessary conditions.Given the status and power grid substation level, nature, taking into account the carrier and optical-fiber communications to conduct multiple forwarding, increasing the instability factor, considering the cost and conditions of the urban construction, Finallydecided to adopt wireless spread-spectrum technology to establish that 11 farm terminal substation communication system. This paper describes the spread spectrum technology and the current system of the building.1.The basic concept of spread-spectrum communication.Spread Spectrum Communication's basic characteristics, is used to transmit information to the signal bandwidth (W) is far greater than the practical information required minimum (effective) bandwidth (△ F) , as the ratio of processing gain GP .G P = W/△FAs we all know, the ordinary AM, FM, or pulse code modulation communications, GP values in the area more than 10 times, collectively, the "narrow-band communication", and spread-spectrum communications GP values as high as hundreds or even thousands of times, can be called "broadband communications."Due to the spread-spectrum signal, it is very low power transmitters, transmission space mostly drowned in the noise, it is difficult to intercepted by the other receiver, only spreading codes with the same (or random PN code) receiver, Gain can be dealt with, and dispreading resume the original signal.2.The technology superiority of spread-spectrum communication.Strong anti-interference, bit error rate is low. As noted above, the spread spectrum communication system due to the expansion of the transmitter signal spectrum, the receiver dispreading reduction signal produced spreading gain, thereby greatly enhancing its interference tolerance. Under the spreading gain, or even negative in the signal-to-noise ratio conditions, can also signal from the noise drowned out Extraction, in the current business communications systems, spread spectrum communication is only able to work in a negative signal-to-noise ratio under the conditions of communication.Anti-multi-path interference capability, increase the reliability of the system. Spread-spectrum systems as used in the PN has a good correlation, correlation is very weak. different paths to the transmission signal can easily be separated and may in time and re-alignment phase, formation of several superimposed signal power, thereby improving the system's performance to receive increased reliability of the system.Easy to use the same frequency, improving the wireless spectrum utilization.Wireless spectrum is very valuable, although long-wave microwave have to be exploited, and still can not meet the needs of the community. To this end, countries around the world are designed spectrum management, users can only use the frequency applications, rely on the channel to prevent the division between the channel interference.Due to the use of spread-spectrum communication related receive this high-tech, low signal output power ( "a W, as a general-100 mW), and will work in the channel noise and thermal noise in the background, easy to duplicate in the same area using the same frequency, can now all share the same narrow-band frequency communications resources.Spread spectrum communication is digital communications, particularly for digital voice and data transmission while, spread spectrum communication with their own encryption, only in the same PN code communication between users, is good for hiding and confidential in nature, facilitating communications business . Easy to use spread-spectrum CDMA communications, voice compression and many other new technologies, more applicable to computer networks and digitization of voice, image information transmission.Communication is the most digital circuits, equipment, highly integrated, easy installation, easy maintenance, but also very compact and reliable. The average failure rate no time was very long.We have decided to adopt the spread-spectrum communication technology construction of 11 farm terminal substation communications system, Due to the spread-spectrum communication by the line-of-sight transmission distance restrictions, has become unstoppable system design premise.If the PUC scheduling Building and 11 substations have stopped, and the problem becomes more complicated, use spread spectrum system on the feasibility greatly reduced. Therefore, we look at the city Aerial topographical map, initially identified has not stopped to consider systems design, and requests the companies used this equipment Spread Spectrum 11 points transmission routing of the measured and the results have been satisfactory.Then spread spectrum wireless equipment market supply of cash, initially, weselected a series of Spread Spectrum Comlink third generation products. Because most of the point-to-point mode, Merit functions of the spread-spectrum equipment in a point-to-multipoint application environments encountered many problems: First is the issue of frequency resources. Even a minimum of 64 kbit / s data rate radio, space also occupied bandwidth 5 MHz, Because 32 of the PN code isolation is only about 15 dBm, the project had to use frequency division multiple access 35 db to get around the theoretical isolation. 11 stations will use 11 frequencies, frequency greater waste of resources. Comlink and Spread Spectrum products in the same frequency to achieve a point-to-multipoint communications.Second antenna erection problems, point-to-point equipment for the main radio station, the main station need to set up a number of terminal antennas, the vast majority of domestic engineering companies used by the U.S. Conifer 24 dBi parabolic semi-cast magnesium grid directional antenna. vertical polarization - 1 m wide, it is difficult to top the layout and avoid flap and the mutual interference, Although the project can be set up to take stratified, or through cooperation and on the road to one or more Omni directional antenna launch, However, as construction of a road and the signal attenuation, transmission result is not satisfactory.In addition, the RF cable lying, The application of network management software such factors we have also decided to adopt the final 1:00 Comlink Multiple Access Spread Spectrum products. Its system configuration, as shown in Figure 2:3.Routing AnalysisCombining visual distance access and use the radio and antenna gain, cable attenuation and environmental factors, and testing the design is reasonable, determinethe attenuation affluent channel capacity. Spread spectrum microwave link attenuation depends on the reliability margin.Attenuation margin calculation formula : F G= G SG + G ANT - L GL - L PLF G——Attenuation margin ;G SG——System Gain (dB);G ANT——Antenna Gain (dBi);L GL——Connectors and cables attenuation (dB);L pL—— Channel attenuation (dB)。
通信工程外文文献翻译
毕业设计(论文)的外文文献翻译原始资料的题目/来源:Fundamentals of wireless communications by David Tse翻译后的中文题目:无线通信基础专业通信工程学生王晓宇学号110240318班号1102403指导教师杨洪娟翻译日期2015年6月15日外文文献的中文翻译7.mimo:空间多路复用与信道建模本书我们已经看到多天线在无线通信中的几种不同应用。
在第3章中,多天线用于提供分集增益,增益无线链路的可靠性,并同时研究了接受分解和发射分解,而且,接受天线还能提供功率增益。
在第5章中,我们看到了如果发射机已知信道,那么多采用多幅发射天线通过发射波束成形还可以提供功率增益。
在第6章中,多副发射天线用于生产信道波动,满足机会通信技术的需要,改方案可以解释为机会波束成形,同时也能够提供功率增益。
章以及接下来的几章将研究一种利用多天线的新方法。
我们将会看到在合适的信道衰落条件下,同时采用多幅发射天线和多幅接收天线可以提供用于通信的额外的空间维数并产生自由度增益,利用这些额外的自由度可以将若干数据流在空间上多路复用至MIMO信道中,从而带来容量的增加:采用n副发射天线和接受天线的这类MIMO 信道的容量正比于n。
过去一度认为在基站采用多幅天线的多址接入系统允许若干个用户同时与基站通信,多幅天线可以实现不同用户信号的空间隔离。
20世纪90年代中期,研究人员发现采用多幅发射天线和接收天线的点对点信道也会出现类似的效应,即使当发射天线相距不远时也是如此。
只要散射环境足够丰富,使得接受天线能够将来自不同发射天线的信号分离开,该结论就成立。
我们已经了解到了机会通信技术如何利用信道衰落,本章还会看到信道衰落对通信有益的另一例子。
将机会通信与MIMO技术提供的性能增益的本质进行比较和对比是非常的有远见的。
机会通信技术主要提供功率增益,改功率增益在功率受限系统的低信噪比情况下相当明显,但在宽带受限系统的高信噪比情况下则很不明显。
通信工程外文资料翻译2篇
南京理工大学毕业设计(论文)外文资料翻译学院(系):电子工程与光电技术学院专业:通信工程姓名:学号:外文出处:1. IEEE TRANSACTIONS ONANTENNAS AND PROPAGATION,VOL. 53,NO.9, SEPTEMBER 20052. IEEE TRANSACTIONS ONMICROWA VE THEORY ANDTECHNIQUES, VOL. 53,NO.6,JUNE 2005附件:1.外文资料翻译译文一;2.外文资料翻译译文二;3.外文原文一;4.外文原文二;注:请将该封面与附件装订成册。
附件1:外文资料翻译译文一在单封装超宽波段无线通信中使用LTCC技术的平面天线作者:Chen Ying and Y.P.Zhang摘要:此通讯提出了一个使用低温度共烧陶瓷技术的平面天线用于超宽频带(UWB)无线通信的单封装解决方案。
该天线具有一个通过微带线反馈的椭圆形的辐射体。
该辐射体和微带线拥有与其它UWBR电路相同的接地板。
实验结果表明原型天线已达到110.9%的带宽,从1.34到5.43 dBi的增益,宽模式和频率从3到10.6GHz 的相对恒定的群延迟。
更多地还发现,标准化天线辐射功率谱密度基本符合FCCS 对于室内UWB系统的发射限制。
关键词:低温共烧陶瓷(LTCC),平面天线,超宽频带(UWB)。
一、引言现在,发展用于窄范围高速度的无线通信网络的超宽频带(UWB)无线电是一个研究热点。
超宽带无线电利用一个7.5 GHz的超宽带宽来交换信息。
使用这样大的带宽,在使U超宽带无线电发挥它最大的作用上存在一些问题.其中的一个主要问题是用于移植系统的超宽带天线的设计。
好的超宽带天线应具有较低的回波损耗,全向辐射模式,从3.1至10.6 GHz的超宽带宽下的高效率,同时也应当满足FCCS规定的发射限制。
现在已经有一些超宽带天线,如钻石偶极子和互补缝隙天线。
它们已被证明适用于超宽带无线电[1] - [4]。
4G网络技术 外文翻译
大连科技学院毕业设计(论文)外文翻译学生姓名李婷专业班级信息工程09(2)班指导教师扬扬职称讲师所在单位电气工程系教研室主任石桂名完成日期 2013年4月12日Talkabout the development trend for mobile communications One,introduction:Mobile communication means between the mobile users, or mobile users and fixed communications between.,With the development of electronic technology, particularly semiconductors, sets Development of circuit and computer technology and mobile communications have enjoyed rapid development. With the expansion of its application fields and on improving the performance requirements, allow mobile communication in technology and development of the theory to a higher level. Since in the 1980s of the 20th century, the mobile communications have become indispensable in modern communication network and one of the fastest means of communication.Reviewing the development of mobile communications, mobile communications development through several stages of development : the first major cellular mobile communication technology of analog mobile communications, the technical characteristics of Cellular network structure overcome the regional capacity low, restricted the scope of activities of the problem. Second G is the cellular mobile communications, cellular systems can provide integrated service digital transmission, and other advantages. Main Characteristics of third G is in addition to providing second of mobile communication system own advantages, overcome its shortcomings, but can also provide broadband multimedia service can provide high - quality video multimedia integrated services, and global roaming. With most of them are now second technology, third technology is still not very successful. but there are already fourth technology vision. 4G standard with more than third of the fourth mobile communication system function.。
NGN下一代网络通信英语翻译
NGN下一代网络通信英语翻译NGN 下一代网络The market for information and communications technology is currently undergoing a structural change. The classic telecommunication networks were planned and implemented for the transfer of specific data such as telephone calls or pure data packages. The recent growth in competition, newrequirements for the market and technological developments have fundamentally changed the traditional attitudes of the telecommunications industry. The present industry is characterized by the rapid growth of broadband connections, the convergence processes of various network technologies and the emergence of a uniform IP standard for individual and mass communications.信息和通信技术市场目前正在经历结构化变革。
传统的电信网络是为电话呼叫或纯数据包这类特定数据的传输规划和实施的。
近来随着竞争的加剧,对市场和技术发展的新需求已经彻底改变了电信业原有的态度。
目前电信业对个人通信和大众通信的特点是:宽带连接的快速增长、各种网络技术的汇聚进程和统一IP通信标准的出现。
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附录一、英文原文:Goals Of True Broad band’s Wireless Next Wave(4G-5G)K.R.Santhi,Prof.V.K.Srivastava,G.SenthilKumaran,Eng. Albert Butare.Kigali Institute of Science Technology and Management (KIST),B.P.3900, Kigali,Rwanda.AbstractAs access technology increases, voice, video,multimedia, and broadband data services are becomingintegrated into the same network. Fourth Generation (4G)is the next generation of wireless networks that will replacethird Generation (3G) networks sometimes in future. 4G isintended to provide high speed, high capacity, low cost perbit, IP based services.4G is all about an integrated, globalnetwork that’s based on an open system approach. The goalof 4G i s to “replace the current proliferation of core cellularnetworks with a single worldwide cellular core networkstandard based on IP for control, video, packet data andV oIP. But while 3G haven’t quite arrived, researchers wantto contribute their ideas to the development of an as-yetundefined "wireless world" that could become operationalby around 2010. This paper deals with the fundamentalsand issues of networks, technologies, spectrum, standards,terminals, services of 4G and about the visions that thenetwork operators and service providers see for theevolution of 4G mobile systems and where is future researchfrom their perspective necessary?Keywords:Wireless, 4G, W-OFDM, MC-CDMA, LAS-CDMA,UWB.I. INTRODUCTIONWhile carriers and handset manufacturers obviously havetheir hands full with 3G, some companies are alreadylooking beyond this next generation of wirelesstechnology and networks. 4G is simply an initiative byacademic R&D labs to move beyond the limitations andproblems of 3G which is having trouble getting deployedand meeting its promised performance and throughput.While this 3G has not completely reached researchers andvendors are expressing growing interest in 4G why? Twomain areas are addressed in these initiatives: An increaseof capacity in the radio link and seamless mobility acrossheterogeneous access networks. Section 2 discusses aboutthe issues of 3G that has created interest towards 4Gdevelopments.Section 3 about evolution and comparison,Section 4 describes about the goals and the vision, section5 explains about some of the technologies for 4G, and inother following sections the applications, the research andother issues for 4G developments are discussed.II. WHY THE LEAP TOWARDS 4G?3G networks are in a very painful phase of theirdevelopment, with early trials yielding disappointingresults, costs ballooning, technical glitches, and networkoperators being forced to deflate expectations based onunrealistic hype. Despite the hype surrounding thehigher-speed 3G mobile networks now underconstruction, the reasons for the leap towards 4G are:A. PerformanceIndustry skeptics say that users will not be able to takeadvantage of rich multimedia content across wirelessnetworks with 3G. 4G communications will featureextremely high-quality video equal to that of high-definitiontelevision. In addition, it will enable wirelessdownloads at speeds exceeding 100 Mbps, about 260times than 3G wireless network.B. InteroperabilityThere are multiple standards for 3G making it difficult toroam and interoperate across networks. We need a globalstandard that provides global mobility and serviceportability so that service provider would no longer bebound by single-system vendors of proprietaryequipment.C. Networking3G are based on primarily a wide-area concept. We needhybrid networks that utilize both wireless LAN (hot spot)concept and cell or base-station WAN design. With 4G,the world would have base stations everywhere, ensuringphone usersconnection to a high-speed networkanywhere, anytime.D. BandwidthWe need wider bandwidth and higher bit rates. The 4Gtechnology, with its transmission speeds of more than 20mbps, would offer high-bandwidth services within thereach of LAN "hotspots," installed in offices,homes,coffee shops,and airport lounges. Away from thesehotspots, customers could connect to souped-up 2Gnetworks for voice and rudimentary data coverage.E. TechnologyUnlike 3G, 4G will more resemble a conglomeration ofexisting technologies rather than an entirely newstandard. Analysts define 4G as a seamless combinationof existing 2G wireless networks with local-areanetworks (LANs) or Bluetooth.F. ConvergenceConvergence involves more than mere technology; it is acoming together of services and markets.We need allnetwork that utilizes IP in its fullest form with convergedvoice and data capability,which the 4G will achieve.G. Cost4G systems will prove far cheaper than 3G, since theycan be built atop existing networks and won't requireoperators to completely retool and won't require carriersto purchase costly extra spectrum.Also an open systemIP wireless environment would probably further reducescosts for service providers by ushering in an era of realequipment interoperability.H. ScalabilityScalability, or the ability to handle increasing numbers ofusers and diversity of services, is more challenging withmobile networks."Design for Scalability," includesinformation that can help you meet changing usagedemands.Because an all IP core layer of 4G is easilyscalable, it is ideally suited to meet this challenge.III.EVOLUTION AND COMPARISON OFBROADBANDWIRELESS1) First Generation (1G):1G wireless mobilecommunication systems, was introduced in the early1980s.1G wireless was analog and supported the firstgeneration of analog cell phones.They include asignaling protocol known as SS7 (Signaling System 7).2) Second Generation (2G): 2G systems, fielded in thelate 1980s, were intended primarily for voicetransmission and was all about digital PCS.3) Third Generation (3G): 3G in wireless will be adeliberate migration to faster, data-centric wirelessnetworks.The immediate goal is to raise transmissionspeeds from 125kbps to 2M bit/sec.4) Fourth Generation (4G): In reality, as of first half of2002, 4G is a conceptual framework for or a discussionpoint to address future needs of a universal high speedwireless network that will interface with wirelinebackbone network seamlessly.IV. THE 4G NETWORK THAT THECELL-HEADSDREAM ABOUT4G can be imagined of as an integrated wireless systemthat enables seamless roaming between technologies.Auser can be operating in cellular technology network andget handed over to a satellite-based network and back to afixed wireless network, depending upon the networkcoverage and preference of charging.A. The GoalsOpen Mobile Alliance’s (OMA) main goal is to makesure different wireless services and devices worktogether, and across countries, operators, and mobileterminals.Other plans in the group's charter include:•Deliver open standards and specifications based onmarket and customer requirements.• Create and promote a common industry view on anarchitectural framework.• Help consolidate standards groups and work inconjunction with other existing standardsorganizations and groups.B. The Composite Vision• 20 Mbps data rates• Streaming Audio/Video• Asymmetric Access• Adaptive Modulation/Coding• Dynamic packet assignment• Smart/Adaptive antennas supportedC. 4G Network Architecture“4G” wireless networks can be realized with an IP-basedcore network for global routing along with morecustomized local-area radio access networks that supportfeatures such as dynamic handoff and ad-hoc routing aswell as newer requirements such as self-organization,QoS, multicasting, content caching, etc..In 4G LANs will be installed in trains and trucks as wellas buildings, or even just formed on an ad-hoc basisbetween random collections of devices that happen tocome within radio range of one other. Routing in suchnetworks will depend on new architectures, already underdevelopment by the IEEE and a European project calledMobile IP Network Developments (MIND).D. The working PrincipleIn 4G-style mobile IP, each cell phone is assigned apermanent "home" IP address, along with a "care-of"address that represents its actual location.When acomputer somewhere on the Internet wants tocommunicate with the cell phone, it first sends apacketto the phone's home address.A directory server on thehome network forwards this to the care-of address via atunnel, as in regular mobile IP. However, the directoryserver also sends a message to the computer informing itof the correct care-of address, so future packets can besent directly.This should enable TCP sessions and HTTPdownloads to be maintained as users move betweendifferent types of networks.Because of the manyaddresses and the multiple layers of subnetting, IPv6 isneeded for this type of mobility.V. TECHNOLOGIES THAT SUPPORT 4GThe revolution in 4G will be the optical networking, thenew air interface, the portable device etc.A. The Transmission Protocols1) OFDM: OFDM is a digital modulation technology inwhich in one time symbol waveform, thousands oforthogonal waves are multiplexed.This is good for highbandwidth digital data transition.2) W-OFDM: W-OFDM enables data to be encoded onmultiple high-speed radio frequencies concurrently. Thisallows for greater security, increased amounts of databeing sent, and the industry’s most efficient use ofbandwidth.W-OFDM enables the implementation of lowpower multipoint RF networks that minimize interferencewith adjacent networks.This enables independentchannels to operate within the same band allowingmultipoint networks and point-to-point backbone systemsto be overlaid in the same frequency band.3) MC-CDMA : MC-CDMA is actually OFDM with aCDMA overlay.Similar to single-carrier CDMA systems,the users are multiplexed with orthogonal codes todistinguish users in (multi-carrier) MC-CDMA.Howeverin MC-CDMA, each user can be allocated several codes,where the data is spread in time or frequency.4) LAS-CDMA:LinkAir Communications is developer of LAS-CDMA(Large Area Synchronized Code Division MultipleAccess) a patented 4G wireless technology. LAS-CDMAenables high-speed data and increases voice capacity andlatest innovative solution, CDD, merges the highlyspectral efficient LAS-CDMA technology with thesuperior data transmission characteristics of TDD.Thisresulting combination makes CDD the most spectrallyefficient, high-capacity duplexing system available today.B. The Radio Interface-UWB RadioTo make 4G really work carries will need to migrate toUltra Wideband (UWB) technology.UWB radiowill deliver essential new wireless andwired bandwidth inexpensively, without using preciousand scarce radio frequencies.Instead,digital video, voiceand data are enabled using modulated pulses of energythat peacefully co-exist alongside traditionalcommunications.UWB radio solves the multipath fadingissues and is 1,000% more process efficient than CDMA.C. The Network-LMDSLocal multipoint distribution system (LMDS) is thebroadband wireless technology used to deliver voice,data, Internet, and video services in the 25-GHz andhigher spectrum (depending on licensing).The acronymLMDS is derived from the following: L(local)—denotes that propagation characteristics ofsignals in this frequency range limit the potentialcoverage area of a single cell site;M (multipoint)—indicates that signals are transmitted ina point-to-multipoint or broadcast method;D (distribution)—refers to the distribution of signals,which may consist of simultaneous voice, data, Internet,and video traffic;S (service)—implies the subscriber nature of therelationship between the operator and the customer.VI. POTENTIAL APPLICATIONS OF 4G1) Virtual Presence: 4G system gives mobile users a"virtual presence" -- for example, always-on connectionsthat keep people involved in business activities regardlessof whether they are on-site or off.2)Virtual navigation:A remote database contains thegraphical representation of streets, buildings, andphysical characteristics of a large metropolis.Blocks ofthis database are transmitted in rapid sequence to avehicle, where a rendering program permits the occupantsto visualize the environment ahead.3) Tele-medicine: 4G will support remote healthmonitoring of patients.For e.g. the paramedic assistingthe victim of traffic accident in a remote location mustaccess medical records and may need videoconferenceassistance from a surgeon for an emergency intervention.The paramedic may need to relay back to the hospital thevictim's x-rays taken locally.4)Tele-geoprocessing applications:Thecombination of geographical information systems (GIS),global positioning systems (GPS), and high-capacitywireless mobile systems will enable a new type ofapplication referred to as tele-geoprocessing.Queriesdependent on location information of several users, inaddition to temporal aspects have many applications.5) Crisis-management applications:Naturaldisasters can affect the entire communicationsinfrastructure is in disarray.Restoring communicationsquickly is essential.With wideband wireless mobilecommunications Internet and video services, could be setup in hours instead of days or even weeks required forrestoration of wireline communications.6) Education :Educational opportunities availableon the internet, for individuals interested in life-longeducation, will be unavailable to client in remote areasbecause of the economic unfeasibility of providingwideband wireline internet access.4G wirelesscommunications provides a cost-effective alternative inthese situations.VII. ROLE OF THE WIRELESSINDUSTRYRECOMMENDATIONSWe are bringing to the attention of professionalsfollowing issues and problems that must be analyzed andresolved:1)Standardization: Standardization of wireless networksin terms of modulation techniques, switching schemesand roaming is an absolute necessity for 4G. We mustpay more attention to general meaning advancedtechnologies.2) Lower Price Points Only Slightly Higher thanAlternatives: The business visionaries should do someeconomic modeling before they start 4G hype. Theyshould understand that 4G data applications likestreaming video must compete with very low costwireline applications.3) More Coordination Among Spectrum RegulatorsAround the World:We must demand almost freespectrum NOT necessarily unlicensed Spectrumregulation bodies must get involved in guiding theresearchers by indicating which frequency band might beused for 4G.4) Regulatory frameworks:Policy and RegulatoryEnvironment which Provides Transparency, Certaintyand a Level Playing Field are necessary. The mostimportant thing is that we should recognize thatregulatory framework is as much an evolving matter astechnology, and be prepared to meet changes with anopen-minded and pragmatic attitude, always keeping theinterests of the industry and consumers in mind.5) More Academic Research:Universities must spendmore effort in solving fundamental problems in radiocommunications (especially multiband and widebandradios, intelligent antennas and signal processing).6) Voice-independent Business Justification Thinking:Business and Technology executives should not bias theirbusiness models by using voice channels as economicdeterminant for data applications.V oice has a built-indemand limit - data applications do not.7) Integration Across Different Network Topologies:Network architects must base their architecture on hybridnetwork concepts thatintegrates wireless wide areanetworks, wireless LANS (IEEE 802.11a, IEEE 802.11b,IEEE 802.11g, IEEE 802.15 and IEEE 802.16), Bluetoothwith fiber-based Internet backbone.Broadband wirelessnetworks must be a part of this integrated networkarchitecture.8) Non-disruptive Implementation: Upgrading from 3G to 4G is expected to be seamless to end-users with nodevice upgrades required.VIII. DEVELOPMENTS IN 4GAT&T is combining W-OFDM and EDGE technologies,to provide broadband mobile downlink access at peakrates of up to 10 Mbps while EDGE offers uplink accessat 384 Kbps with an 800KHz bandwidth in a high-mobilityenvironment.Sun Microsystems Laboratories are building 4G wirelesstechnologies that promise tointegrate voice and web datain an IP-based mobile communications.The Government of Karnataka in India has signed a MoUwith Charmed Technologies Inc from Beverly Hills,California and Software Technology Parks of India inKarnataka to develop 4G wireless technology. Theproject plan to use wireless technology based on theIEEE802.11a and IEEE802.11b standards for wirelessLAN for the underlying network is designed to support adata rate of up to 11Mbps and 54Mbps respectively. Thegoal is to get 6 billion people connected to the wirelessInternet by 2010.NTT DoCoMo and Hewlett-Packard Company &MOTOmediacollaboration will explore new mobile serviceconcepts in which people, places and things will be ableto interact, thereby bridging the real and the cyber world.MOTO-media is expected to enable high performancestreaming of multimedia content to mobile users.DoCoMo and HP aim to nish the shared study of basictechnology by 2003 and hope to push for 4G in 2006.IX. SUGGESTIONSWe would like to give the following suggestions for thedevelopment of 4G mobile technologies:1. Technologies like 4G must be developed to integrateinto a more flexible network that grow within thenetwork so that we don't have to scarp the old network toimplement the next generation, the generations to come.2. The very big challenge for developing a technology isproper human resource for building high quality systems.Big organization, which is engaged in software andsystem development, should rapidly go for tie-ups witheducational institutes for better manpower and knowledgemanagement.3. We talk about mobile multimedia that 4G will supportbut in reality people are not going to watch TV whilethey walk down the street. Likewise people will not buyCoca Cola at vending machines with a cell phone. Quitoften services conjured up by the engineering side of thevendor organizations has little to do with the reality. Sowireless industry should ponder well about marketdemand and invest money so that they will not be at loss.X.CONCLUSION4G should make a significant difference and addperceived benefit to an ordinary person’s life over 3G.We should drop the 2.5G, 3G, 4G speak altogether wherean additional “G” means merely an increase in capacity.What really means something for the users are newservices, integration of services, applications etc. Ourgoal is to struggle to get a “G”eneration of standards sothat we can take our phone anywhere in the world andaccess any service or communicate with any other userany way we want that will offer connectivity soinexpensively. In short, 4G or WWWW (World WideWireless web) should be a more intelligent technologythat interconnects the entire world without limits.二、英文翻译:下一代无线宽带的目标(4G—5G)摘要:随着接入技术的增长,语音、视频、多媒体和宽带数据业务正在集成到同一个网络中去。