wifi简介

Direction 5: build "attractive" content together
4:Building material union

5G embedded Wi-Fi module application vehicle network Connecting vehicles to reduce traffic accidents
Biblioteka BaiduA.
B.
Network architecture based on all IP
Sharing open business platform and operation support system
2:Complementarity of application

Speech and VoWLAN data services under wide area coverage and area coverage Utilization of wireless channel resources handheld terminal and Laptop/PDA combination The connection between the mobile phone and the computer is no longer wired, and the wireless is all able to do it.
The main characteristics of WiFi
The coverage of radio waves is relatively wide The speed of transmission is very fast and meets the needs of personal and social information. The doorsill of the manufacturer is low and the price of the equipment is low Small signal power Working at the IMS band of 2.4GHZ, global unification
Network
protocol
1:Basic Service Set,BSS:The most basic service unit of the network. The simplest unit of service can be made up of only two sites. A site can dynamically connect (Associate) to the basic service unit. 2:Distribution System,DS:The allocation system is used to connect different basic service units. The medium used by the distribution system (Medium) is completely separated from the basic service unit logically, though physically they may be the same medium, such as the same wireless band. 3:Access Point,AP:The access point not only has the identity of the common site, but also has the function of accessing the distribution system.
11b 2.4G band, the transmission rate is increased to 5.5M and 11M 11A 5.8G band, the transmission rate is increased to 54M The first generation of WLAN standards launched by IEEE The transmission rate of the 2.4G band is 1M
3:Business operation

Direction 1: regional electronic map
Direction 2: personalized Portal pages
Direction 3: Location Location Direction 4: advertising for Wi-Fi free
The application field of WiFi

Network media:Long distance calls (including international long distance), web pages, email, music downloads, and digital photos Handheld:Intelligent mobile phone Day-to-day leisure:Travel, office Passenger train Comfort station

The background of WiFi
The transmission rate of 2.4G band and 5.8G band is increased to 300M Compatible 11a/11b/11g The transmission rate of the frequency band and 60G band below 6G is not less than 1Gbit/s
Brief introduction of WiFi Technology
1551100403 王晓娜
1551100404 周子璇 1551100405 邱越
What is WiFi The background of WiFi The structure of WiFi The main characteristics of WiFi The application field of WiFi The development prospect of WiFi
5:Cover the world
Making every corner of the world covered wireless networks sounds like a beautiful idea, but an American technology company is going to turn it into reality. The company is expected to launch hundreds of mini satellites to the near earth orbit by June 2015, which will continuously release the wireless network signals to the earth, covering all parts of the world, and use any electronic terminals to connect to the wireless network.
What is WiFi

The common thing is a wireless router WIFI (WIreless-FIdelity) wireless connection is a technology that can connect personal computers, handheld devices (such as PAD, mobile phone) and other terminals in wireless way. In fact, it is a high frequency radio signal. Wireless network in the category of WLAN is "wireless compatibility authentication", which is essentially a kind of commercial authentication, and is also a wireless networking technology.
The transmission rate is raised to the 54M 2.4G band Compatible 11B
802.11g 2003年 802.11a/b 1999年
802.11n 2009年
802.11ac 802.11ad 2012年
802.11 1997年
The structure of WiFi
The development prospect of WiFi
1:Fusion 3G
From the aspects of coverage, transmission rate, basic business category, mobile speed, forward expansion and evolution trend, 3G and WLAN are complementary relations that can take advantages and avoid disadvantages.
Hardware
equipment
1:Communication interface aspect：In 2010, basically the form of USB interface is adopted. There are also a few parts of PCIE and SDIO. PCIE's market share should be small, and the price of one to one is expensive, and its practicability is not strong, so many functions of integration will not be used. In fact, it is also a waste. 2:Power supply aspect:Most of them use 5V direct power supply, and some also use the power sharing in the main board design, directly using 3.3V power supply. 3:Antenna processing mode:It can have built-in PCB board antenna or ceramic antenna; it can also connect the antenna extension line through the I-PEX joint, and then let the antenna be outside.