一种基于选择式ARQ协议的自适应反馈方案

Adaptive Feedback Scheme Based on SR_ARQ

自动重传请求(ARQ)协议对于保证通信网络的可靠传输起着关键性作用。无差错反馈环境下基于ARQ协议的网络传输性能已经得到广泛研究,但是实际环境中反馈信道不可避免的存在一定程度的干扰,尤其是无线通信环境。本文提出了一种在反馈信道不可靠状态下的自适应反馈方案,通过记录接收数据包个数自适应调整反馈周期、根据接收状态封装不同格式的应答包、简单预测反馈信道质量状况后采用发送应答包不同次数的方法,有效地保证了反馈信息的可靠性,避免了不必要的重传。对协议性能的理论分析和仿真结果表明,在一定的传输条件下自适应反馈方案能够获得较高的系统吞吐量。

Automatic-repeat-request （ARQ） protocol plays a key role in communication networks to ensure reliable delivery of packet data. Its performance has been widely studied under reliable feedback environment, but actual feedback channel is noisy inevitably. This paper provides an adaptive feedback scheme based on selective-repeat-ARQ under unreliable feedback transmission, which ensures reliability of feedback and improves acknowledge efficiency. This scheme uses counting method to adjust feedback period and constructs different style frames according to packets＇ states and sends different frames different times after simply channel forecasting. Theoretic analysis and simulation results show that, adaptive scheme can achieve higher throughput performance compared to the traditional scheme.