摘要： 车载网衰落信道质量变化频繁，传统速率自适应算法不能选择合适传输速率。为此，提出一种适用于车路网的速率自适应算法。该算法基于发送端的接收信号强度指示(RSSI)预测进行速率选择，即用发送端路边设施测量接收到ACK报文的RSSI值，预测下次传输时的信道质量。模拟结果表明，该算法能提高信道质量预测的准确度，在不同的信道衰落程度下，取得比RBAR算法和SampleRate算法更高的系统吞吐率。

关键词: 车载网, 车路通信, 速率自适应, 指数平滑, 保守预测, 信道衰落

Abstract: The traditional rate adaptive algorithm can not select the appropriate transmission rate under the vehicular network of which channel quality changes quickly. This paper proposes a rate adaptive algorithm for vehicle to roadside network. The algorithm is based on Receive Signal Strength Indication(RSSI) of transmitting terminal to predict and select rate, Roadside Unit(RSU) of transmitting terminal measures RSSI value of received ACK messages to predict next time transmission channel quality. Simulation results show that the algorithm for channel quality prediction can achieve higher accuracy and higher system throughput under different degree of channel fading, compared with RBAR algorithm and SampleRate algorithm.

Key words: vehicular network, vehicle to roadside communication, rate adaptation, exponential smoothing, conservative forecast, channel fading

中图分类号: 

• TP393