Wireless Communications Digital Communications

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通信常见英语词汇完整版

1. WLAN--Wireless Local Area Network, 中文名叫: 无线局域网2. WiFi--Wireless Fidelity ，是一种无线联网的技术（俗称：无线宽带）3. DT--Drive Test ，路测，是无线网络优化数据采集的方法。

4. CQT--Call Quality Test ，呼叫质量测试或定点网络质量测试5. GPS--Global Positioning System （全球定位系统）的简称6. KPI--Key Performance indicator 关键性能指标7. SIM 卡--Subscriber Identification Module 用户身份鉴别模件8. FTTH--Fiber To The Home 光纤到户9. Channel-- 海峡, 频道, 通道，通信中指信息传输的通道（信道）10. Frequency-- 频率，通信中特指无线信号的频率11. Mobile station-- 移动的设备，移动台，特指手机12. Base station-- 基站，用于接收和发送手机信号13. Short message-- 短消息，短信14. Communication-- 通信15. Network-- 网络16. Mobile community-- 移动通信17. 4G--G 是generation （一代）的简称，特指第四代移动通信技术18. Protocol-- 协议，网络之间互联遵循的规范Online--在线的，名词可指网游 On li ne bankin g--网上银行 Wireless--无线，通信领域范畴指的是无线电或无线电波 Broadcast--广播Cell--细胞；电池；蜂房的巢室；单人小室。

移动通信网络中特指小区（基站信号覆盖的范围） Satellite Com mun icatio n-- 卫星通信Ch ina Mobile--中国移动 China Telecom--中国电信 China Unicom--中国联通 Opted fiber-- 光纤 Cable--电缆Man ageme nt--管理 DC--direct curre nt ，直流电AC--alternati ng curre nt，交流电 DT--Drive Test ，无线网络路测 CQT--Call Quality Test ，呼叫质量测试（通信里常称为拨打测试） 19.20.21.22.23. 24.25.26.27.28.29.30.31.32.33.34. 35.36.37.38.Accepta nee of work-- 工程验收Project startup -- 工程启动Prelimi nary in specti on-- 初验Con structi on quality-- 工程质量39. Project acco un ti ng-- 项目核算40. Engin eeri ng supervisi on-- 工程督导41. Project ma nager-- 项目经理42. Project engin eer--项目工程师43. Project completio n-- 项目竣工44. Un pack ing in specti on-- 开箱验货45. Time limit for a project-- 工期46. 抽样量化与编码:sampling,quantizing and coding47. 话路:speech channel 幅值：amplitude value48. 抽样频率:sampling frequency49. 抽样速率：sampling rate 脉冲流：stream of pulses50. 重复率:repetition rate 编码过程:coding process51. 模拟信号:analog signal52. 传输质量:transmission quality53. 数字通信:digital communication54. 数字传输:digital transmission55. 含噪声的环境:noisy environment56. 传输路由：transmission path57 信噪比：signal-to-noise ratio58.信号电平:signal levels 噪声功率:noise power59地面系统：terrestrial system60. 二进制传输:binary tra nsmissi on61. 反向操作：reverse operati on62.8-位码序列:8-digit sequenee63. 接受端:receiving termi nal 帧格式:frame format64. 同步字：synchronization word65. 串行接口serial in terface显示终端CRT term in al发送器与接收器tra nsmitter and receiver数据传输data tran smissi on数据流data stream闲置状态the idle state传号电平mark level空号电位space level起始位start bit停止位stop bitT 秒的持续时间durati on of T seco nds奇偶校检位parity bit错误标志error flag 传输错误tra nsmissi on error下降沿fallinf edge 符号间的空格in tersymbol space接收机的定时receiver timi ng 本地时钟local clock 磁带magnetic tape 控制比特con trol bit 逻辑1 电平logical 1 level二进制数据binary data通信卫星commu ni cati on satellite微波设备microwave facilities 调制器与解调器modulator and demodulator缓冲器buffer定时信号timi ng sig nals同步脉冲syn chr oni zati on pulses时隙time slot移位寄存器shift register传输媒体tra nsmissi on medium线形衰弱lin ear atte nuati on信息安全in formati on security键盘keyboard数据终端data termi nals网络资源：n etwork resource信息服务：in formatio n services远程终端：remote termi nals互联的系统：interconn ected systems命令：comma nd电子邮件：electro nic mail主机：host无线信道：wireless cha nnels搜索工具：search ing tools用户界面：user in terface存取：access文本信息：textual messages协议：protocol超文本协议：hypertext protocolthe 分布在全世界的计算机的巨大网络：gaint network of computers located all overworld主干系统：backb one system全国范围的网络：n atio nwild network电子会议：electro nic con fere nces实时对话：live con versati on最大的信息库the largest repository of the computers on the net 网络设备资源：n etwork facilities resources在网上的绝大多数计算机：the vast majority of the computer on the netUNIX 操作系统：the UNIX operating system在因特网和你的PC机之间传送数据的方法： a way to move data between theand your PC方便的搜索工具：the convenient search ing tools联网的超文本协议：the :n etwork hypertextprotoco l光纤通信:optical fiber commu ni cati ons光源：light source波长：wavele ngth激光器：laser色散：dispersi on传输介质：tran smissi on medium多模光纤：multi-mode fiber长途干线：lon g-houl trunks单模光纤：sin ger-mode fiber带宽：ban dwidth带宽用户：wideba nd subscriber纤维光学：fiber-optics商用技术：commercial tech no loge门限电流：threshod curre nt光检测器：photodetector波分复用：wavele ngth multiplex ing纤维光网络：fiber-optic network视频带宽：video ban dwidth长途传输：long dista nee tra nsmissi on中继距离：repeater spac ing已装光纤的总长度：the total len gth of in stalled fiber 长途通信系统：lon g-haul telecommu nicatio nsystem低衰减的石英纤维：the low-loss silica fiber波分复用：wavele ngth multiplexi ng带宽用户环路系统：widebe nd subscriber loop system多纤连接器:multifibre conn ectors设计寿命：projected lifetime光源：light source单模光纤：sin gle-mode fibre分布反馈式激光器：distributed-feedback laser信息容量：in formatio n capacity交换体系：switch ing hierarchy带宽业务：broadband services公用电信网public telecommu nicatio n n etwork本地环路local loop交换节点switching 1 nodeinternet双绞线 twisted pair外部呼叫 externalcall 二线连接 two wire connection收费中心 toll cen ter电路交换网 circuit-switch ing n etwork电话用户 telepho ne subscriber数据流量 data traffic链路 link中继线 trunk半双工的 half-duplex全双工的 full-duplex中间交换节点 in termediate switchi ng node音频电路voice-freque ncy circuit汇接交换机 tan dem switch拓扑 topology多媒体 multimedia交互环境in teractive en vior nment视频压缩 video compress in高清晰度电视 high defi ni tio n televisi on数字信号处理器 digital sig nal processor点播业务 on-dema nd services视频服务器 video servers全球通信 global commu ni cati ons灵活性 flexibility端到端的数字连接 en d-to-e nd digital conn ectivity开放网络 ope n n etwork语声编码voice en cod ing综合业务数字网 in tegrated services digital n etwork系统结构 in frastructure国际标准化组织 Intern ati onal Organi zati on for Stan dardizati on 通信载体 commu ni cati on carriers传输媒体 tran smissi on medium接口设备 in terface equipme nt带宽限制 ban dwidth limitati on 交换设备 switchi ng equipme nt语音编码 voice en cod ing脉码调制 pulse code modulati on基本接入 basic accessX.25协议 X.25 protocol电视信号 televisi on sig nals 宽带业务 n arrowba nd services基本接入 basic access端局数字数据系统 digital data systemsend officeteleservicetelexradio waves grou nd antenna coaxial直接广播系统 direct broadcast systemvideo-on-dema nd in teractive services 交互式视频点播业务multimedia en virome nt 多媒体环境 visual images 视频图象hard disk storage 硬盘存储colour mon itor 彩显the standards of multimedia 多媒体标准 moti on pictures 活动图象consumer quality of video and audio 顾客质量的视频和音频 broadcast images 广播图象high defin ition televisi on 高清晰度电视 cod ing algorithms 编码算法digital sig nals processor 数字信号处理器端到端的时延 en d-to-e nd delay抖动繁忙小时芯片技术高清晰度电视运行也维护 jitterpeak hourschip tech no logyhigh defi niti on televisi on operations and maintenance 现有的公用网络 the exist ing public 硬件、软件和应用 hardware,software 存储 storage n etwork and applicati ons 彩显 colour mon iter全活动图象 full motion picture视频编码器 visio n en coder字节 bytemixture of hardware,software and applicatio ns 硬件、软件和应用层 in teractive en vir onment 交互环境personal desk top computers video compressi on 视频压缩the vision encoder 视频编码器个人桌面电脑电信业务用户电报无线电波地面天线同轴的。

视听说,wireless,communication

The preview of the wireless communication future.
The preview of the wireless communication future.
◆ Hardware Design
Small, lightweight, low power, cheap, high frequency operation
the sales of their goods.
Wi-Fi
How doeswireless communication influence our l i f e ?
无线能量传输
Wireless energy transfer is a process whereby electrical energy is transmitt e from a power source to an electrica电l力l负o荷 ad that does not have a built-in power sourc without the use of interconnecting s There are two different fundamen 线 methods for wireless energy transfer. It can help us charge our digital product without wire which used to bother us a lot
Sumner Tainter invented and patented the photophone, a v. 取得…的
telep 音o机n； e 电at话机conducted au i利o权
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数据通信毕业论文外文文献英文翻译

郑州轻工业学院本科毕业设计（论文）——英文翻译题目差错控制编码解决加性噪声的仿真学生姓名专业班级通信工程05-2 学号 12院（系）计算机与通信工程学院指导教师完成时间 2009年4月26日英文原文:Data communicationsGildas Avoine and Philippe OechslinEPFL, Lausanne, Switzerlandfgildas.avoine, philippe.oechsling@ep.chAbstractData communications are communications and computer technology resulting from the combination of a new means of communication. To transfer information between the two places must have transmission channel, according to the different transmission media, there is wired data communications and wireless data communications division. But they are through the transmission channel data link terminals and computers, different locations of implementation of the data terminal software and hardware and the sharing of information resources.1 The development of data communicationsThe first phase: the main language, through the human, horsepower, war and other means of transmission of original information.Phase II: Letter Post. (An increase means the dissemination of information)The third stage: printing. (Expand the scope of information dissemination)Phase IV: telegraph, telephone, radio. (Electric to enter the time)Fifth stage: the information age, with the exception of language information, there are data, images, text and so on.1.1 The history of modern data communicationsCommunication as a Telecommunications are from the 19th century, the beginning Year 30. Faraday discovered electromagnetic induction in 1831. Morse invented telegraph in 1837. Maxwell's electromagnetic theory in 1833. Bell invented the telephone in 1876. Marconi invented radio in 1895. Telecom has opened up in the new era. Tube invented in 1906 in order to simulate the development of communications.Sampling theorem of Nyquist criteria In 1928. Shannong theorem in 1948. The invention of the 20th century, thesemiconductor 50, thereby the development of digital communications. During the 20th century, the invention of integrated circuits 60. Made during the 20th century, 40 the concept of geostationary satellites, but can not be achieved. During the 20th century, space technology 50. Implementation in 1963 first synchronized satellite communications. The invention of the 20th century, 60 laser, intended to be used for communications, was not successful. 70 The invention of the 20th century, optical fiber, optical fiber communications can be developed.1.2 Key figuresBell (1847-1922), English, job in London in 1868. In 1871 to work in Boston. In 1873, he was appointed professor at Boston University. In 1875, invented many Telegram Rd. In 1876, invented the telephone. Lot of patents have been life. Yes, a deaf wife.Marconi (1874-1937), Italian people, in 1894, the pilot at his father's estate. 1896, to London. In 1897, the company set up the radio reported. In 1899, the first time the British and French wireless communications. 1916, implementation of short-wave radio communications. 1929, set up a global wireless communications network. Kim won the Nobel Prize. Took part in the Fascist Party.1.3 Classification of Communication SystemsAccording to type of information: Telephone communication system, Cable television system ,Data communication systems.Modulation by sub: Baseband transmission,Modulation transfer.Characteristics of transmission signals in accordance with sub: Analog Communication System ,Digital communication system.Transmission means of communication system: Cable Communications,Twisted pair, coaxial cable and so on.And long-distance telephone communication. Modulation: SSB / FDM. Based on the PCM time division multiple coaxial digital base-band transmission technology. Will gradually replace the coaxial fiber.Microwave relay communications:Comparison of coaxial and easy to set up, low investment, short-cycle. Analog phone microwave communications mainly SSB / FM /FDM modulation, communication capacity of 6,000 road / Channel. Digital microwave using BPSK, QPSK and QAM modulation techniques. The use of 64QAM, 256QAM such as multi-level modulation technique enhance the capacity of microwave communications can be transmitted at 40M Channel 1920 ~ 7680 Telephone Rd PCM figure.Optical Fiber Communication: Optical fiber communication is the use of lasers in optical fiber transmission characteristics of long-distance with a large communication capacity, communication, long distance and strong anti-interference characteristics. Currently used for local, long distance, trunk transmission, and progressive development of fiber-optic communications network users. At present, based on the long-wave lasers and single-mode optical fiber, each fiber road approach more than 10,000 calls, optical fiber communication itself is very strong force. Over the past decades, optical fiber communication technology develops very quickly, and there is a variety of applications, access devices, photoelectric conversion equipment, transmission equipment, switching equipment, network equipment and so on. Fiber-optic communications equipment has photoelectric conversion module and digital signal processing unit is composed of two parts.Satellite communications: Distance communications, transmission capacity, coverage, and not subject to geographical constraints and high reliability. At present, the use of sophisticated techniques Analog modulation, frequency division multiplexing and frequency division multiple access. Digital satellite communication using digital modulation, time division multiple road in time division multiple access.Mobile Communications: GSM, CDMA. Number of key technologies for mobile communications: modulation techniques, error correction coding and digital voice encoding. Data Communication Systems.1.4 Five basic types of data communication system:（1）Off-line data transmission is simply the use of a telephone or similar link to transmit data without involving a computer system.The equipment used at both ends of such a link is not part of a computer, or at least does not immediately make the data available for computer process, that is, the data when sent and / or received are 'off-line'.This type of data communication is relatively cheap and simple.（2）Remote batch is the term used for the way in which data communication technology is used geographically to separate the input and / or output of data from the computer on which they are processed in batch mode.（3）On-line data collection is the method of using communications technology to provide input data to a computer as such input arises-the data are then stored in the computer (say on a magnetic disk) and processed either at predetermined intervals or as required.（4）Enquiry-response systems provide, as the term suggests, the facility for a user to extract information from a computer.The enquiry facility is passive, that is, does not modify the information stored.The interrogation may be simple, for example, 'RETRIEVE THE RECORD FOR EMPLOYEE NUMBER 1234 'or complex.Such systems may use terminals producing hard copy and / or visual displays.（5）Real-time systems are those in which information is made available to and processed by a computer system in a dynamic manner so that either the computer may cause action to be taken to influence events as they occur (for example as in a process control application) or human operators may be influenced by the accurate and up-to-date information stored in the computer, for example as in reservation systems.2 Signal spectrum with bandwidthElectromagnetic data signals are encoded, the signal to be included in the data transmission. Signal in time for the general argument to show the message (or data) as a parameter (amplitude, frequency or phase) as the dependent variable. Signal of their value since the time variables are or not continuous, can be divided into continuous signals and discrete signals; according to whether the values of the dependent variable continuous, can be divided into analog signals and digital Signal.Signals with time-domain and frequency domain performance of the two most basic forms and features. Time-domain signal over time to reflect changing circumstances. Frequency domain characteristics of signals not only contain the same information domain, and the spectrum of signal analysis, can also be a clear understanding of the distribution ofthe signal spectrum and share the bandwidth. In order to receive the signal transmission and receiving equipment on the request channel, Only know the time-domain characteristics of the signal is not enough, it is also necessary to know the distribution of the signal spectrum. Time-domain characteristics of signals to show the letter .It’s changes over time. Because most of the signal energy is concentrated in a relatively narrow band, so most of our energy focused on the signal that Paragraph referred to as the effective band Bandwidth, or bandwidth. Have any signal bandwidth. In general, the greater the bandwidth of the signal using this signal to send data Rate on the higher bandwidth requirements of transmission medium greater. We will introduce the following simple common signal and bandwidth of the spectrum.More or less the voice signal spectrum at 20 Hz ~ 2000 kHz range (below 20 Hz infrasound signals for higher than 2000 KHz. For the ultrasonic signal), but with a much narrower bandwidth of the voice can produce an acceptable return, and the standard voice-frequency signal gnal 0 ~ 4 MHz, so the bandwidth of 4 MHz.As a special example of the monostable pulse infinite bandwidth. As for the binary signal, the bandwidth depends on the generalThe exact shape of the signal waveform, as well as the order of 0,1. The greater the bandwidth of the signal, it more faithfully express the number of sequences.3 The cut-off frequency channel with bandwidthAccording to Fourier series we know that if a signal for all frequency components can be completely the same through the transmission channel to the receiving end, then at the receiving frequency components of these formed by stacking up the signal and send the signal side are exactly the same, That is fully recovered from the receiving end of the send-side signals. But on the real world, there is no channel to no wear and tear through all the Frequency components. If all the Fourier components are equivalent attenuation, then the signal reception while Receive termination at an amplitude up Attenuation, but the distortion did not happen. However, all the transmission channel and equipment for different frequency components of the degree of attenuation is differentSome frequency components almost no attenuation, and attenuation of some frequency components by anumber, that is to say, channel also has a certain amount of vibrationIncrease the frequency characteristics, resulting in output signal distortion. Usually are frequency of 0 Hz to fc-wide channel at Chuan harmonic lost during the attenuation does not occur (or are a very small attenuation constant), whereas in the fc frequency harmonics at all above the transmission cross Decay process a lot, we put the signal in the transmission channel of the amplitude attenuation of a component to the original 0.707(that is, the output signal Reduce by half the power) when the frequency of the corresponding channel known as the cut-off frequency (cut - off frequency).Cut-off frequency transmission medium reflects the inherent physical properties. Other cases, it is because people interested in Line filter is installed to limit the bandwidth used by each user. In some cases, because of the add channel Two-pass filter, which corresponds to two-channel cut-off frequency f1 and f2, they were called up under the cut-off frequency and the cut-off frequency.This difference between the two cut-off frequency f2-f1 is called the channel bandwidth. If the input signal bandwidth is less than the bandwidth of channel, then the entire input signal Frequency components can be adopted by the Department of channels, which the letter Road to be the output of the output waveform will be true yet. However, if the input signal bandwidth greater than the channel bandwidth, the signal of a Frequency components can not be more on the channel, so that the signal output will be sent with the sending end of the signal is somewhat different, that is produced Distortion. In order to ensure the accuracy of data transmission, we must limit the signal bandwidth.4 Data transfer rateChannel maximum data transfer rate Unit time to be able to transfer binary data transfer rate as the median. Improve data transfer rate means that the space occupied by each Reduce the time that the sequence of binary digital pulse will reduce the cycle time, of course, will also reduce the pulse width.The previous section we already know, even if the binary digital pulse signal through a limited bandwidth channel will also be the ideal generated wave Shape distortion, and when must the input signal bandwidth, the smaller channel bandwidth, output waveformdistortion will be greater. Another angle Degree that when a certain channel bandwidth, the greater the bandwidth of the input signal, the output signal the greater the distortion, so when the data transmissionRate to a certain degree (signal bandwidth increases to a certain extent), in the on-channel output signal from the receiver could not have been Distortion of the output signal sent to recover a number of sequences. That is to say, even for an ideal channel, the limited bandwidth limit System of channel data transfer rate.At early 1924, H. Nyquist (Nyquist) to recognize the basic limitations of this existence, and deduced that the noise-free Limited bandwidth channel maximum data transfer rate formula. In 1948, C. Shannon (Shannon) put into the work of Nyquist 1 Step-by-step expansion of the channel by the random noise interference. Here we do not add on to prove to those now seen as the result of a classic.Nyquist proved that any continuous signal f (t) through a noise-free bandwidth for channel B, its output signal as a Time bandwidth of B continuous signal g (t). If you want to output digital signal, it must be the rate of g (t) for interval Sample. 2B samples per second times faster than are meaningless, because the signal bandwidth B is higher than the high-frequency component other than a letter has been Road decay away. If g (t) by V of discrete levels, namely, the likely outcome of each sample for the V level of a discrete one, The biggest channel data rate Rm ax as follows:Rmax = 2Blog 2 V (bit / s)For example, a 3000 Hz noise bandwidth of the channel should not transmit rate of more than 6,000 bits / second binary digital signal.In front of us considered only the ideal noise-free channel. There is noise in the channel, the situation will rapidly deteriorate. Channel Thermal noise with signal power and noise power ratio to measure the signal power and noise power as the signal-to-noise ratio (S ignal - to -- Noise Ratio). If we express the signal power S, and N express the noise power, while signal to noise ratio should be expressed as S / N. However, people Usually do not use the absolute value of signal to noise ratio, but the use of 10 lo g1 0S / N to indicate the units are decibels (d B). For the S / N equal 10 Channel, said its signal to noise ratio for the 1 0 d B; the same token, if the channel S / N equal to one hundred, then the signal to noiseratio for the 2 0 d B; And so on. S hannon noise channel has about the maximum data rate of the conclusions are: The bandwidth for the BH z, signal to noise ratio for the S / N Channel, the maximum data rate Rm ax as follows:Rmax = Blog 2 (1 + S / N) (bits / second)For example, for a bandwidth of 3 kHz, signal to noise ratio of 30 dB for the channel, regardless of their use to quantify the number of levels, nor Fast sampling rate control, the data transfer rate can not be greater than 30,000 bits / second. S h a n n o n the conclusions are derived based on information theory Out for a very wide scope, in order to go beyond this conclusion, like you want to invent perpetual motion machine, as it is almost impossible.It is worth noting that, S hannon conclusions give only a theoretical limit, and in fact, we should be pretty near the limit Difficult.SUMMARYMessage signals are (or data) of a magnetic encoder, the signal contains the message to be transmitted. Signal according to the dependent variable Whether or not a row of values, can be classified into analog signals and digital signals, the corresponding communication can be divided into analog communication and digital communication.Fourier has proven: any signal (either analog or digital signal) are different types of harmonic frequencies Composed of any signal has a corresponding bandwidth. And any transmission channel signal attenuation signals will, therefore, Channel transmission of any signal at all, there is a data transfer rate limitations, and this is Chengkui N yquist (Nyquist) theorem and S hannon (Shannon) theorem tells us to conclusions.Transmission medium of computer networks and communication are the most basic part of it at the cost of the entire computer network in a very Large proportion. In order to improve the utilization of transmission medium, we can use multiplexing. Frequency division multiplexing technology has many Road multiplexing, wave division multiplexing and TDM three that they use on different occasions.Data exchange technologies such as circuit switching, packet switching and packetswitching three have their respective advantages and disadvantages. M odem are at Analog phone line for the computer's binary data transmission equipment. Modem AM modulation methods have, FM, phase modulation and quadrature amplitude modulation, and M odem also supports data compression and error control. The concept of data communications Data communication is based on "data" for business communications systems, data are pre-agreed with a good meaning of numbers, letters or symbols and their combinations.参考文献[1]C.Y.Huang and A.Polydoros,“Two small SNR classification rules for CPM,”inProc.IEEE Milcom,vol.3,San Diego,CA,USA,Oct.1992,pp.1236–1240.[2]“Envelope-based classification schemes for continuous-phase binary Frequency-shift-keyed modulations,”in Pr oc.IEEE Milcom,vol.3,Fort Monmouth,NJ,USA,Oct.1994,pp. 796–800.[3]A.E.El-Mahdy and N.M.Namazi,“Classification of multiple M-ary frequency-shift keying over a rayleigh fading channel,”IEEE m.,vol.50,no.6,pp.967–974,June 2002.[4]Consulative Committee for Space Data Systems(CCSDS),Radio Frequency and Modulation SDS,2001,no.401.[5]E.E.Azzouz and A.K.Nandi,“Procedure for automatic recognition of analogue and digital modulations,”IEE mun,vol.143,no.5,pp.259–266,Oct.1996.[6]A.Puengn im,T.Robert,N.Thomas,and J.Vidal,“Hidden Markov models for digital modulation classification in unknown ISI channels,”in Eusipco2007,Poznan,Poland, September 2007,pp.1882–1885.[7]E.Vassalo and M.Visintin,“Carrier phase synchronization for GMSK signals,”I nt.J.Satell. Commun.,vol.20,no.6,pp.391–415,Nov.2002.[8]J.G.Proakis,Digital Communications.Mc Graw Hill,2001.[9]L.Rabiner,“A tutorial on hidden Markov models and selected applications in speechrecognition,”Proc.IEEE,vol.77,no.2,pp.257–286,1989.英文译文：数据通信Gildas Avoine and Philippe OechslinEPFL, Lausanne, Switzerlandfgildas.avoine, philippe.oechsling@ep.ch摘要数据通信是通信技术和计算机技术相结合而产生的一种新的通信方式。

数字通信的优势英语作文

数字通信的优势英语作文Advantages of Digital Communication。

Digital communication refers to the transmission of information from one person to another through digital devices such as computers, smartphones, and tablets. In recent years, digital communication has become increasingly popular due to its many advantages over traditional communication methods. In this essay, I will discuss the advantages of digital communication.Firstly, digital communication is fast and efficient. With just a few clicks, you can send an email, text message, or instant message to anyone in the world. This is much faster than traditional communication methods such as sending a letter through the mail or making a phone call.In addition, digital communication allows you to communicate with multiple people at the same time, which is especially useful for businesses and organizations.Secondly, digital communication is convenient and accessible. With the widespread use of smartphones and tablets, people can communicate with each other anytime, anywhere. This is particularly useful for people who travel frequently or work remotely. Digital communication also allows people to access information and resources from anywhere in the world, which is essential in today's globalized economy.Thirdly, digital communication is cost-effective. Compared to traditional communication methods such as sending a letter through the mail or making a long-distance phone call, digital communication is much cheaper. This is especially important for businesses and organizations that need to communicate with customers and clients on a regular basis.Fourthly, digital communication is environmentally friendly. Traditional communication methods such as sending a letter through the mail or making a phone call require the use of paper, ink, and other resources. Digital communication, on the other hand, is paperless and requiresminimal resources. This is important for the environment, as it reduces the amount of waste and pollution generated by traditional communication methods.In conclusion, digital communication has many advantages over traditional communication methods. It is fast, efficient, convenient, accessible, cost-effective, and environmentally friendly. As technology continues to advance, digital communication will become even more important in our daily lives.。

信息通信专业英语词汇及常用英语口语

信息通信专业英语词汇及常用英语口语以下是一些信息通信专业的英语词汇和一些常用的英语口语表达，供参考：信息通信专业英语词汇：munication Networks:•Wired Network: 有线网络•Wireless Network: 无线网络•LAN (Local Area Network): 局域网•WAN (Wide Area Network): 广域网2.Telecommunications:•Telecommunication Systems: 电信系统•Fiber Optic Communication: 光纤通信•Satellite Communication: 卫星通信3.Data Transmission:•Data Rate: 数据传输速率•Bandwidth: 带宽•Modulation: 调制•Demodulation: 解调4.Internet Technologies:•Internet Protocol (IP): 互联网协议•TCP/IP (Transmission Control Protocol/Internet Protocol): 传输控制协议/互联网协议•URL (Uniform Resource Locator): 统一资源定位符5.Wireless Communication:•Mobile Communication: 移动通信•5G Technology: 5G 技术•Bluetooth: 蓝牙•Wi-Fi: 无线网络6.Security:•Cybersecurity: 网络安全•Encryption: 加密•Firewall: 防火墙•Authentication: 身份验证7.Hardware and Software:•Router: 路由器•Switch: 交换机•Protocol: 协议•Application Software: 应用软件8.VoIP (Voice over Internet Protocol):•VoIP Call: 互联网电话•SIP (Session Initiation Protocol): 会话初始协议常用英语口语表达：1.Greetings:•"Hello! How are you doing?"•"Good morning/afternoon/evening."2.Making Requests:•"Could you please explain that in more detail?"•"Would you mind providing some more information?"3.Giving Opinions:•"In my opinion,..."•"From my perspective,..."4.Describing Technology:•"This device operates on the latest technology."•"The software is user-friendly and intuitive."5.Problem-Solving:•"Let's troubleshoot the issue together."•"We need to identify the root cause of the problem."6.Meetings and Presentations:•"I'd like to present the key findings of our project."•"Are there any questions or concerns?"7.Expressing Agreement/Disagreement:•"I completely agree with your point."•"I see what you're saying, but I have a different perspective."8.Closing a Conversation:•"It was great talking to you."•"Let's keep in touch. Have a great day!"这些词汇和表达方式应该能够涵盖信息通信专业中的许多常见主题和情境。

Wireless Communication Connecting the World

Wireless Communication Connecting the World Wireless communication has revolutionized the way people connect with each other and the world around them. It has enabled instant communication across vast distances, allowing people to stay in touch with friends and family, conduct business, and access information from virtually anywhere. The impact of wireless communication on society has been profound, shaping the way we live, work, and interact with one another.From a personal perspective, wireless communication has greatly enhanced my ability to stay connected with loved ones. Whether it's through text messages, phone calls, or video chats, I can easily reach out to friends and family members, no matter where they are in the world. This has made it possible to maintain strong relationships despite physical distance, fostering a sense of closeness and connection that would have been much more difficult to achieve in the past.In addition to its impact on personal relationships, wireless communication has also transformed the way we conduct business. Mobile devices and wireless networks have made it possible for professionals to work remotely, collaborate with colleagues in different locations, and access important information on the go. This has led to increased flexibility and productivity in the workplace, as well as the ability to conduct business on a global scale with ease.Furthermore, wireless communication has had a significant impact on education and access to information. With the rise of mobile devices and wireless internet, students and learners of all ages can access a wealth of knowledge and educational resources from anywhere with an internet connection. This has democratized access to information, allowing people from all walks of life to pursue learning and personal growth in ways that were previously unimaginable.On a broader societal level, wireless communication has also played a crucial role in emergency response and disaster relief efforts. During natural disasters or other emergencies, wireless communication networks have been vital in coordinating rescue andrelief operations, as well as keeping affected populations informed and connected. This has undoubtedly saved lives and mitigated the impact of disasters in countless situations.However, it's important to acknowledge that the widespread adoption of wireless communication has also raised concerns about privacy and security. As people increasingly rely on wireless devices to store and transmit sensitive information, the risk of data breaches and cyber attacks has become a significant issue. This has led to ongoing debates about the balance between convenience and security in the digital age, as well as the need for robust measures to protect personal and sensitive information.In conclusion, wireless communication has had a profound and far-reaching impact on society, transforming the way we connect with one another, conduct business, access information, and respond to emergencies. While it has undoubtedly brought about many positive changes, it has also raised important questions about privacy and security in the digital age. As we continue to navigate the evolving landscape of wireless communication, it will be crucial to prioritize the responsible use of technology while harnessing its potential for positive impact.。

双工无线语音数据传输系统外文翻译

Triple wireless voice data transmission system designStudent :,Instructor :, UniversityEvery day, in our work and in our leisure time, we come in contact with and use a variety of modern communication media, the most common being the telephone, radio, television, and the Internet. Though these media we are able to communicate (nearly) instantaneously with people on diffident continents, transact our daily business, and receive information about various developments and events of note that occur all around the world. Electronic mail and facsimile transmission have made it possible to rapidly communicate written message across great distances.Wireless communications. The development of wireless communications stems from the works of Oersted, Faraday, Gauss, Maxwell, and Hertz. In1820, Oersted demonstrated that an electric current produces a magnetic field. On August 29,1831,Michael Faraday showed that an induced current is produced by moving a magnet in the vicinity of a conductor. Thus, he demonstrated that a changing magnetic field produces an electric field. With this early work as background, James C. Maxwell in 1864 predicted the existence of electromagnetic radiation and formulated the basic theory that has been in use for over a century. Maxwell’s theory was verified experimentally by Hertz in 1887.In 1894, a sensitive device that could device that could detect radio signals, called the coherer, was used by its inventor Oliver Lodge to demonstrate wireless communication over a distance of 150 yards at Oxford, England. Guglielmo Marconi is credited with the development of wireless telegraphy. Marconi demonstrated the transmission of radio signals at a distance of approximately 2 kilometers in 1895. Two years later, in 1897 , he patented a radio telegraph system and established the Wireless Telegraph and Signal Company. On December 12, 1901, Marconi received a radio signal at Signal Hill in Newfoundland, which was transmitted from Cornwall, England, a distance of about 1700 miles.The invention of the vacuum tube was especially instrumental in the development of radio communication system .The vacuum diode was invented by Fleming in 1904 and the vacuum triode amplifier was invented by De Forest in 1906, as previously indicated. The invention of the triode made radio broadcast possible in the early part of the twentieth century. Amplitude modulation (AM) broadcast was initiated in 1920 when radio station KDKA, Pittsburgh, went on the air. From that date, AM radio broadcasting grew rapidly across the country and around the world. The super heterodyne AM radio receiver, as we know it today, was invented by Edwin Armstrong during World War I. Another significant development in radio communications was the invention of Frequency modulation (FM), also by Armstrong.In 1933, Armstrong built and demonstrated the first FM communication system. However, the use of FM was slow to develop compared with AM broadcast. It was not until the end of World War II that FM broadcast gained in popularity and developed commercially.The first television system was built in the United States by V. K. Zworykin and demonstrated in 1929. Commercial television broadcasting began in London in 1936 by the British Broadcasting Corporation(BBC) . Five years later the Federal Communications Commission(FCC) authorized television broadcasting in the United States.ELEMENTS OF AN ELECTRICAL COMMUNICA SYSTEM Electrical communication systems are designed to send messages or information from a source that generates the message to one more destinations. In general, a communication system can be represented by the functional block diagram shown . The information generated by the source may be of the form of voice (speech source), a picture (image source), or plain text in some particular language, such as English , Japanese, German , French, etc. An essential feature of any source that generates information is that its output is described in probabilistic terms; i.e., the output of a source is not deterministic. Otherwise, there would be no need to transmit the message.A transducer is usually required to convert the output of a source into an electrical signal that is suitable for transmission. For example, a microphone serves as the transducer that converts an acoustic speech signal. At the destination, a similar transducer is required to convert the electrical signals that are received into a form that is suitable for the user; e.g., acoustic signals, images, etc.The heart of the communication system consists of three basic parts, namely, the transmitter, the channel, and the receiver. The functions performed by these three elements are described next.The Transmitter. The Transmitter converts the electrical signal into a form that is suitable for transmission though the physical channel or transmission medium. For example, in radio and TV broadcast, the Federal Communications Commission (FCC) specifies the frequency range for each transmitting station. Hence, the transmitter must translate the information signal to be transmitted into the appropriate The Transmitter range that matches the frequency allocation assigned to the transmitter. Thus, signal transmitted by multiple radio station do not interfere with one another. Similar functions are performed in telephone communication systems where the electrical speech signals from many users are transmitted over the same wire.In general, the transmitter performs the matching of the message signal to the channel by a process called modulation. Usually, modulation involves the use of the information signal to systematically vary either the amplitude, frequency, or phase of a sinusoidal carrier. For example, in AM radio broadcast, the information signal that is transmitted is contained in the amplitude variations of the sinusoidal carrier, which is the center frequency in the amplitude modulation. In FM radio broadcast., the information signal that is transmitted is contained in the frequency variations of thesinusoidal carrier. This is an example of frequency modulation. Phase modulation (PM) is yet a third method for impressing the information signal on a sinusoidal carrier.In general, carrier modulation such as AM, FM, and PM is performed at the transmitter, as indicated above, to convert the information signal to a form that matches the characteristics of the channel. Thus, though the process of modulation, the choice of the type of modulated in frequency to match the allocation of the channel. The choice of the type of modulation is based on several factors, such as the amount of bandwidth over the channel, the type of noise and the interference that the signal encounters in transmission. In any case, the modulation process makes it possible to accommodate the transmission of multiple messages from many users over the same physical channel.In addition to modulation, other functions that are usually performed at the transmitter are filtering of the information-bearing signal , amplification of the modulated signal, and in case of wireless transmission, radiation of the signal by means of a transmitting antenna.The channel. The communications channel is the physical medium that is used to send the signal from the transmitter to the receiver. In wireless transmission, the channel is usually the atmosphere (free space). On the other hand, telephone channels usually employ a variety of physical media, including wirelines, optical fiber cables, and wireless (microwave radio). Whatever the physical medium for signal transmission, the essential feature is that the transmitted signal is corrupted in a random manner by a variety of possible mechanisms. The most common from of signal degradation comes in the form of additive noise ,which is generated at the front end of the receiver, where signal amplification is performed. This noise is often called thermal noise. In wire less transmission, additional additive disturbances are man-made noise, and atmospheric noise picked up by a receiving antenna. Automovile ignition noise is an example of man-made noise, and electrical lightning discharges from thunderstorms is an example of atmospheric noise. Interference from other users of the channel is another form of additive noise that often arises in both wireless and wire line communication systems .In some radio communication channels, such as the ionospheric channel that is used for long range ,short-wave radio transmission, another form of signal degradation is multipath propagation. Such signal distortion is characterized as a nonadditive signal disturbance which manifests itself as time variations in the signal amplitude, usually called fading .Both additive and nonadditive signal distortions are usually characterized as random phenomena and described in statistical terms. The effect of these signal distortions must be taken into account on the design of the communication system.In the design of a communication system, the system, the system designer works with mathematical models that statistically characterize he signal distortion encountered on physical channels. Often, the statistical description that is used in mathematical model is a result of actual empirical measurements obtained from experiments involving signal transmission over such channels .In such cases , there isa physical justification for the mathematical model used in the design of communication systems. On the other hand, in some communication system designs ,the statistical characteristics of the channel may vary significantly with time. In such cases, the system design may designer may design a communication system that is robust to the variety of signal distortions. This can be accomplished by having the system adapt some of its parameters to the channel distortion encountered.The receiver. The function of the receiver is to recover the message signal contained in the received signal. If the message signal is transmitted by carrier modulation, the receiver performs carrier demodulation in order to extract the message from the sinusoidal carrier. Since the signal demodulation is performed in the presence of additive noise and possibly other signal distortion, the demodulated message signal is generally degraded to some extent by the presence of these distortions in the received signal. As we shall see, the fidelity of the additive noise, the type and strength of any other additive interference, and the type of any nonadditive interference.Besides performing the primary function of signal demodulation, the receiver also performs a number of peripheral functions, including signal filtering and noise suppression.Digital Communication SystemAn electrical communication system in rather broad terms based on the implicit assumption that message signal is a continuous timevarying waveform. We refer to such continuous-time signal waveforms as analog sources. Analog signal can be transmitted directly via modulation over the communication channel and demodulated accordingly at the receiver. We call such a i communication system an analog communication system.Alternatively, an analog source output may be converted into a digital form and the message can be transmitted via digital modulation as a digital signal at the receiver. There are some potential advantage to transmitting an analog signal by means of digital modulation. The most important reason is that signal fidelity is better controlled though digital transmission than analog transmission. In particular, digital transmission allows us to regenerate the digital signal in long-distance transmission, thus eliminating effects of noise at each regeneration point. In contrast, the noise added in analog transmission is amplified along with the signal when amplifiers are used periodically to boost the signal level in long-distance transmission. Another reason for choosing digital transmission over analog is that the analog message signal may be highly redundant. With digital processing, redundancy may be removed prior to modulation, thus conserving channel bandwidth. Yet a third reason may be that digital communication systems are often cheaper to implement.In some applications, the information to be transmitted is inherently digital; e.g., in the form of English text, computer data, etc. In such cases, the information source that generates the data is called a discrete (digital)source.In a digital communication systems , the some applications, the functional operations performed at the transmitter and receiver must be expanded to includemessage signal discrimination at the transmitter and message signal synthesis or interpolation at the receiver. Additional functions include redundancy removal, and channel coding and decoding.The source output may be either an analog signal, such as audio or video signal, or a digital signal , such as the output of a computer which is discrete in time and has a finite number of output characters. In a digital communication system, the message produced by the source are usually converted into a sequence of binary digits as possible. In other words, we seek inefficient representation of the source output of either an analog or a digital source into a sequence of binary digits is called source encoding or date compression.The sequence of binary digits from the coerce encoder, which we call the information sequence is passed to the channel encoder. The purpose of the channel encoder is to introduce, in a controlled manner, some redundancy in binary information sequence which can be used at the receiver to overcome the effects of noise and interference encountered in the transmission of the signal though the channel. Thus the added redundancy serves to increase the reliability of the received data and improves the fidelity in decoding the deceived signal. In fact, redundancy serves in the information sequence aids the receiver in decoding the desired information sequence .The binary sequence at the output of the channel encoder is passed to the digital modulator, which servers as the interface to the communications channel. Since nearly all of the communication channels encountered in practice are capable of transmitting electrical signals (waveforms), the primary purpose of the digital modulator is to map the binary information sequence into signal waveforms.At the receiving end of a digital communication system, the digital demodulator processes the channel-corrupted transmitted waveform and reduces reduce each waveform to a signal number that represents an estimate of the transmitted data symbol (binary or Mary) . When there is no redundancy in the transmitted information, the demodulator must decide which of the M waveform was transmitted in any given time interval. A measure of how well the demodulator and encoder perform is the frequency with which errors occur in the decoded sequence.As a final step, when an analog output is desired, the source decoder accepts the output sequence from the channel and , from knowledge of the source-encoding method used, attempts to reconstruct the original signal from the source.双工无线语音数据传输系统的设计学生：学院指导老师：汉大学在日常的工作和生活中，人们每天都要接触和使用大量的现代通信系统和通信媒介，其中最常见的是电话，无线电广播，电视和因特网。

近距离无线数字通信的技术标准

近距离无线数字通信的技术标准Near-field wireless digital communication refers to the technology that allows devices to communicate with each other over short distances, typically within a few centimeters to a few meters. 近距离无线数字通信是指允许设备在短距离内进行通信的技术，通常在几厘米到几米之间。

This technology has become increasingly popular in recent years due to the rise of IoT devices, smart homes, and contactless payment systems. 这项技术近年来因物联网设备、智能家居和非接触式支付系统的兴起而日益流行。

One of the key aspects of near-field wireless digital communicationis its convenience and ease of use. 近距离无线数字通信的一个关键方面是其便利性和易用性。

Devices equipped with this technology can easily transfer data and information without the need for physical cables or complex setup processes. 配备这种技术的设备可以轻松传输数据和信息，无需物理电缆或复杂的设置过程。

This makes it ideal for scenarios where quick and seamless communication is essential, such as mobile payments, file sharing between devices, and smart home automation. 这使其非常适用于需要快速和无缝通信的场景，比如移动支付、设备间文件共享和智能家居自动化等情况。

对数码通讯的看法英语作文

对数码通讯的看法英语作文In recent years, digital communication has become an increasingly important part of our daily lives. From social media to instant messaging, we rely on digital communication to stay connected with friends, family, and colleagues. In this essay, I will explore the benefits and drawbacks of digital communication and offer my own perspective on this topic.One of the biggest advantages of digital communicationis its convenience. With just a few clicks or taps, we can send messages, photos, and videos to anyone, anywhere inthe world. This has made it easier than ever to stay in touch with people we care about, even if they live on the other side of the planet. In addition, digital communication has made it possible to collaborate with colleagues and work remotely, which can be a huge benefitfor people who live in remote areas or have mobility issues.Another advantage of digital communication is its speed.Unlike traditional mail or telephone calls, digital messages can be sent and received instantly, allowing us to communicate in real-time. This can be especially useful in emergency situations or when we need to make quick decisions.However, digital communication also has its drawbacks. One of the biggest concerns is privacy. With so much personal information being shared online, there is always a risk of identity theft or cyberbullying. In addition,digital communication can be addictive, leading to a loss of productivity or social isolation.Despite these concerns, I believe that digital communication is a valuable tool that has enriched ourlives in many ways. However, it is important to use it responsibly and be mindful of the potential risks. By staying informed and taking steps to protect our privacy, we can continue to enjoy the benefits of digital communication while minimizing the drawbacks.In conclusion, digital communication has revolutionizedthe way we communicate and connect with others. While there are certainly risks and drawbacks associated with this technology, I believe that the benefits outweigh the costs. As long as we use digital communication responsibly and remain vigilant about our privacy, we can continue to enjoy the many benefits of this powerful tool.。

Wireless Communication Technologies

Wireless Communication Technologieshave revolutionized the way we stay connected with each other and access information. From the early days of basic radio transmissions to the modern world of 5G networks, wireless communication technologies have evolved rapidly and have become an integral part of our everyday lives.One of the most commonly used wireless communication technologies is Wi-Fi, which allows us to connect our devices to the internet without the need for physical cables. Wi-Fi operates on radio frequencies and can be found in homes, offices, cafes, and public spaces around the world. With the increasing demand for high-speed internet access, the latest Wi-Fi standards, such as Wi-Fi 6, have been introduced to provide faster and more reliable connections.Another popular wireless communication technology is Bluetooth, which enables us to wirelessly connect our devices, such as smartphones, laptops, and headphones, to each other. Bluetooth technology has evolved over the years, with the latest version, Bluetooth 5.2, offering improved speed, range, and security features. Bluetooth is widely used for wireless audio streaming, file sharing, and connecting smart home devices.In addition to Wi-Fi and Bluetooth, cellular networks play a crucial role in wireless communication. Mobile phones rely on cellular networks, such as 4G LTE and 5G, to connect to the internet and make voice calls. These networks use a network of towers and base stations to provide coverage over large geographical areas. The introduction of 5G networks has brought faster speeds, lower latency, and increased capacity, paving the way for new technologies like autonomous vehicles and smart cities.Satellite communication is another important wireless technology that enables global connectivity, especially in remote areas where traditional infrastructure is limited. Satellites orbiting the Earth transmit signals to and from ground stations, providing services like satellite TV, GPS navigation, and internet access. Satellite communication is also essential for disaster relief efforts and military operations.The Internet of Things (IoT) is a rapidly growing field that relies on wireless communication technologies to connect billions of devices and sensors to the internet. IoT devices, such as smart thermostats, wearables, and industrial sensors, use wireless technologies like Bluetooth, Wi-Fi, and cellular networks to collect and transmit data for monitoring and control purposes. The widespread adoption of IoT is driving the development of new wireless standards and protocols to ensure secure and reliable communication.Overall, wireless communication technologies have transformed the way we communicate, work, and live. The advancements in wireless technologies have enabled us to stay connected anytime, anywhere, and have opened up new possibilities for innovation and collaboration. As we continue to embrace the digital age, wireless communication technologies will play an increasingly important role in shaping our future.。

无线通信的英语作文

无线通信的英语作文Title: The Evolution of Wireless Communication。

Wireless communication has revolutionized the way humans interact, exchange information, and conduct business. From the early days of telegraphy to the present era of 5G networks, the journey of wireless communication has been marked by remarkable advancements and innovations.The inception of wireless communication can be traced back to the late 19th century with the invention of theradio by Guglielmo Marconi. This groundbreaking technology enabled long-distance transmission of signals without the need for physical wires. The radio laid the foundation for subsequent developments in wireless communication, serving as a precursor to modern technologies such as Wi-Fi, Bluetooth, and cellular networks.One of the most significant milestones in the historyof wireless communication was the advent of cellularnetworks. In 1973, Motorola engineer Martin Cooper made the first public call using a handheld mobile phone, marking the birth of the cellular era. Since then, cellular technology has undergone rapid evolution, transitioning from analog to digital systems and culminating in the widespread deployment of 4G LTE networks.The emergence of smartphones and other mobile devices has further propelled the demand for wireless connectivity. Today, wireless communication is not only about voice calls but also encompasses a wide range of data services, including internet browsing, video streaming, and social media interaction. The advent of 5G technology promises even faster data speeds, lower latency, and greater network capacity, paving the way for the Internet of Things (IoT) and smart cities.In addition to cellular networks, Wi-Fi has become an integral part of everyday life. Originally developed as a wireless alternative to Ethernet for local area networking, Wi-Fi has evolved into a ubiquitous technology found in homes, offices, cafes, and public spaces worldwide. Thelatest iterations of Wi-Fi, such as Wi-Fi 6, offer significant improvements in speed, efficiency, and reliability, catering to the ever-increasing demand for high-bandwidth applications.Bluetooth is another key wireless technology that enables short-range communication between devices.Initially conceived as a way to eliminate cables for connecting peripherals such as keyboards and mice, Bluetooth has evolved into a versatile protocol used for audio streaming, file sharing, and IoT connectivity. The latest version of Bluetooth, Bluetooth Low Energy (BLE), is particularly well-suited for battery-powered devices and IoT sensors.The future of wireless communication holds immense promise, driven by ongoing research and development in areas such as millimeter-wave technology, massive MIMO (Multiple Input Multiple Output), and cognitive radio. These advancements aim to address the growing demand for faster speeds, greater reliability, and ubiquitous connectivity across diverse environments.However, along with its numerous benefits, wireless communication also poses challenges such as spectrum congestion, security vulnerabilities, and privacy concerns. As the reliance on wireless technology continues to grow,it becomes increasingly important to address these issues through effective regulation, standardization, and cybersecurity measures.In conclusion, wireless communication has come a long way since its humble beginnings, transforming the world in profound ways. From the radio waves of the past to the 5G networks of the future, the evolution of wireless communication reflects humanity's relentless pursuit of connectivity and innovation. As we stand on the brink of a new era driven by emerging technologies, the possibilities for wireless communication are limitless, promising afuture where connectivity knows no boundaries.。

无线通信技术在数字化中的应用

应用Technology ApplicationI G I T C W 技术172DIGITCW2021.021 无线通信技术的定义如今使用无线通信技术的人员与日俱增。

无线通信技术是通过无线的方式，将光波，电磁波等介质传送到终端，通过编码传递信息，最终实现通信。

根据无线通信覆盖的范围不同，可以分为局域网，城域网以及广域网。

2 无线通信技术的发展历程无线通信技术的发展历经了5个阶段，实现了从固定的位置进行通信到移动通信，从军队等特殊群体使用到普遍化，进入了普通百姓家。

发展阶段如下：第一个阶段，无线通信主要用于军队，采用了电子管以及短波频技术，适用范围较为局限。

第二阶段主要采用半导体技术，是实现移动电话与公共电话串联起来的里程碑，是无线通信网络发展上质的飞跃。

第三阶段是初频段达到800MHz ，提出了蜂窝系统的概念并进行了AMPS 试验。

第四阶段迎来了第二代数字移动通信的大规模发展，从特殊领域的使用逐渐向个人业务推广，TACS ，PCS 等多种系统百花齐放。

第五阶段是第三代移动通信开始流行，此时的移动通信可以满足移动数据及多媒体的需要，实现了从第二代到第三代的过渡。

3 无线通信技术的特点3.1 具有较强的信息处理功能无线通信技术是通过互联网进行的信息传递，可以实现跨越距离和时间的限制，信息处理功能强大，平日里常说的互联网记忆即是在网络中可以随时进行信息的查询与搜索。

3.2 抗干扰能力强无线通信技术是采用的二进制转化系统，具有较强的抗干扰能力，读取信息数据等速度快且准。

3.3 使用范围广无线通信可以实现图片，文字的传播，且能实现视频，语音的远程传输。

3.4 降低了管理成本无线通信的应用，降低了企业在基础设施上投入的费用，节约了资源，同时也使得员工的工作强度降低，也便于企业的日常管理。

4 无线通信技术的现状无线通信技术改变了人们的交流方式，使得人与人之间的沟通变得更加的便捷，也改变了传统的信息传输的方式，信息传输速度快，使得不出门就能知道天下事成为了可能。

数字交流英语作文

数字交流英语作文Digital communication has become an integral part of our daily lives. It's hard to imagine a world without smartphones, emails, or social media platforms. We use digital tools to stay connected with friends and family, share our thoughts and experiences, and even conduct business transactions.I love the convenience of digital communication. With just a few taps on my phone, I can send a message to someone on the other side of the world. It's so much faster and easier than writing a letter and waiting for it to be delivered by snail mail. Plus, I can send photos and videos to make my messages more engaging and personal.But digital communication isn't always perfect. Sometimes, it can lead to misunderstandings or even conflicts. When we're communicating through a screen, it's easy to misinterpret someone's tone or intention. We can't always see facial expressions or hear voice inflections,which can make it harder to understand each other.That's why it's important to be mindful of how we communicate digitally. We should try to be clear and concise in our messages, and avoid using sarcasm or irony that might be misinterpreted. It's also a good idea。

Mobile and Wireless Communications

Mobile and Wireless Communications Mobile and wireless communications have revolutionized the way we connect with each other, access information, and conduct business. From the early days of basic cell phones to the advanced smartphones we have today, these technologies have become an integral part of our daily lives. The convenience and flexibility that mobile and wireless communications offer have made them essential tools for communication and productivity.One of the key benefits of mobile and wireless communications is the ability to stay connected on the go. With smartphones and mobile devices, we can make calls, send messages, and access the internet from virtually anywhere. This level of connectivity has transformed how we communicate with each other, enabling us to stay in touch with friends, family, and colleagues no matter where we are. Whether we're traveling for work or on vacation, we can always stay connected through our mobile devices.In addition to personal communication, mobile and wireless communications have also had a significant impact on businesses and industries. With the rise of mobile apps and mobile-friendly websites, businesses can reach their customers anytime, anywhere. This has opened up new opportunities for marketing, sales, and customer engagement. Mobile payments have also become increasingly popular, allowing customers to make purchases with a simple tap of their phone. This convenience has led to a surge in mobile commerce, with more and more businesses embracing mobile technology to reach their customers.However, the widespread adoption of mobile and wireless communications has also raised concerns about privacy and security. With so much personal information stored on our devices, there is a risk of data breaches and cyber attacks. From malware and phishing scams to unauthorized access to sensitive information, the potential threats to our privacy and security are ever-present. As we rely more and more on our mobile devices for everyday tasks, it's important to take precautions to protect our data and ensure our online safety.Another challenge of mobile and wireless communications is the issue ofdigital divide. While many of us take for granted the access to high-speedinternet and mobile devices, there are still large segments of the population thatlack access to these technologies. This digital divide can exacerbate existing inequalities, limiting opportunities for education, employment, and social connections. Bridging the digital divide requires investment in infrastructure, policies to promote digital inclusion, and efforts to increase digital literacy among underserved communities.Despite these challenges, the potential of mobile and wireless communications to improve our lives and society is immense. From telemedicine and remote learning to smart cities and IoT devices, these technologies have the power to drive innovation and create positive change. By harnessing the capabilities of mobile and wireless communications, we can build a more connected, efficient, and inclusive world for all. As we continue to embrace and adapt to the ever-evolving landscape of mobile technology, it's important to consider the impact on individuals, communities, and the broader society.。

wireless communication

Smoke signals on the Great Wall
The history of wireless communication.
The world's first wireless telephone conversation occurred in 1880, when Alexander Graham Bell and Charles Sumner Tainter invented and patented the photophone, a telephone that conducted audio conversations wirelessly over modulated light beams (which are narrow projections of electromagnetic waves).
Wireless mice and keyboard
The history of wireless communication.
The history of wireless communication.
The first wireless networks were developed in the Pre-industrial age. These systems transmitted information over line-of-sight distances (later extended by telescopes) using smoke signals, torch signals, flashing mirrors, signal flares, or semaphore flags. Observation stations were built on hilltops and along roads to relay these messages over large distances.