Reserarch And Implementation Of Rate Adaptation Algorithms In Internet Of Vehicle

The Internet of Vehicle (IOV) is a kind of the Internet of Things which extend to the field of Intelligent Transportation Systems, with high technical and economic feasibility, as well as a very promising future. Wireless communication technology--the802.11protocol is the foundation of IOV applications. Its physical layer has different modulation and coding abilities which support multi-rate transmission. But it does not define the rate selection method, so rate adaptive algorithm becomes to the hotspot of wireless arena.The rate adaptation selection depending on the quality of channel can not only ensure the data received correctly, but also meet the QoS need of different services. And this method can improve the throughput and save power consumption. Connectionless data transmission is the key of data communication application, channel estimation and rate selection is also the key of rate adaptive algorithm. By reading a lot of literatures, we presented a rate adaptive algorithm for broadcast data frame transmission in IOV, and then implemented based on Multiband Atheros Driver for Wifi, final analyze the performance. Contents and results are as follows:Firstly, the concept, hierarchy and development of IOV are reviewed.Secondly, wireless communication technologies of IOV are analyzed. According to comparison of multiple wireless technologies, we found the key technology of IOV data communication is DSRC (Dedicated Short Range Communication). And WAVE (Wireless Access in Vehicular Environments) is composed of IEEE802.11p and IEEE1609protocol family; it’s the improvement of DSRC.Thirdly, by means of analyzing the rate adaptive algorithms and comparing the performance of several algorithms, we proposed a VRAB (Vehicle Rate-Adaptive Broadcast) algorithm, which channel assessment is a method base on combination of statistics and measurement.Fourthly, MadWifi wireless driver platform structure, and as well as the processes the sending and receiving are analyzed, then VRAB algorithm implement on MadWifi.Fifthly, the hardware and software of the experimental platform, as well as the test environment simulated scenarios are described. Then the VRAB algorithms transplanted in the test platform based on MadWifi is compared with fixed rate Algorithm. The test data shows that VRAB algorithm is more suitable than the fixed rate in IOV, which can improve the network throughput.Finally, summary the work this paper has done and the research works also be prospected in the future.