1、Brief introduction of WiFi Technology,1551100403 王晓娜1551100404 周子璇1551100405 邱越,What is WiFi,The common thing is a wireless routerWIFI(WIreless-FIdelity)wireless connection is a technology that can connect personal computers,handheld devices(such as PAD,mobile phone)and other terminals in wireless w
2、ay.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 background of WiFi,The first generation of WLAN standards launch
3、ed by IEEEThe transmission rate of the 2.4G band is 1M,11b 2.4G band,the transmission rate is increased to 5.5M and 11M11A 5.8G band,the transmission rate is increased to 54M,The transmission rate is raised to the 54M2.4G bandCompatible 11B,The transmission rate of 2.4G band and 5.8G band is increas
4、ed to 300MCompatible 11a/11b/11g,The transmission rate of the frequency band and 60G band below 6G is not less than 1Gbit/s,The structure of WiFi,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.PCI
5、Es 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 boa
6、rd 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.,Network protocol 1:Basic Service Set,BSS:The most basic service u
7、nit 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 com
8、pletely 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.,The main characteristic
9、s of WiFi,The coverage of radio waves is relatively wideThe 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 lowSmall signal powerWorking at the IMS band of 2.4GHZ,global unification,Th
10、e application field of WiFi,Network media:Long distance calls(including international long distance),web pages,email,music downloads,and digital photosHandheld:Intelligent mobile phoneDay-to-day leisure:Travel,officePassenger trainComfort station,The development prospect of WiFi,1:Fusion 3G From the
11、 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.Network architecture based on all IPSharing open business platform and operation support system,2
12、:Complementarity of applicationSpeech and VoWLANdata services under wide area coverage and area coverageUtilization of wireless channel resources handheld terminal and Laptop/PDA combinationThe connection between the mobile phone and the computer is no longer wired,and the wireless is all able to do
13、 it.,3:Business operationDirection 1:regional electronic mapDirection 2:personalized Portal pagesDirection 3:Location LocationDirection 4:advertising for Wi-Fi freeDirection 5:build attractive content together4:Building material union5G embedded Wi-Fi module application vehicle networkConnecting veh
14、icles to reduce traffic accidents,5:Cover the worldMaking 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.,
