The Implementation Of Platform Based On802.11P Protocol

With the development of intelligent transportation system, vehicle networking research is concerned by more and more researchers. Vehicle ad hoc network (VANET) provides wireless access in a high-speed mobile environment, and builds a wireless communication between the vehicle and the vehicle, the vehicle and the roadside infrastructure. VANET can solve the traffic congestion problem, ensure traffic safety and traffic efficiency, and provide the vehicle driver assistance applications and in-car entertainment.This paper is to build platform compliance with IEEE802.11p protocol, including two parts, the analysis of WAVE/IEEE1609series protocols and driver of network card. Then set up the platform with wireless network module and test the performance of the platform. IEEE802.11p is based on extensive testing and analyses of wireless communications in a mobile environment. The difference between the IEEE802.11p amendment and IEEE802.11a is small. The PHY layer of the standard uses the same signal processing as the OFDM PHY used in the IEEE802.11a standard. But the bandwidth in the IEEE802.11p is10MHz, so parameters in the time domain are doubled and data rates are halved, and the maximum transfer rate is27Mbps. The allowable transmit power is defined to provide larger communication ranges for vehicular scenarios. The MAC layer of the standard defines a new MIB (Management information base), dot11OCBENABLED, used by stations communicating outside of the context of a BSS. Through research and analysis, selecting DCMA-86P2network card as IEEE802.11p wireless communication module is more convenient and feasible conducive to build platform than the use of existing products and implementation method based on FPGA. The thesis proposes the method of developing IEEE802.11p driver based on ath5k source code, including channel bandwidth and other physical layer parameters. At last, set mode and frequency of the network card with Linux Wireless Extensions such as iw, iwconfig. Then test performance in the ad-hoc network architecture by iperf, and verify the usage of IEEE802.11p driver.