Ad Hoc网络中基于传输状态的自适应退避算法

提出一种适用于Ad Hoc网络、基于传输状态的自适应退避(ABTS)算法.为了预测信道状态,ABTS算法采用局部竞争节点估计的方法,并且针对不同的信道状态采用退避窗口乘性或线性增加的策略.鉴于重传多次的数据容易被丢弃,ABTS赋予重传多次的数据高传输优先级,以减少数据丢失.理论分析和仿真结果表明,ABTS算法能满足Ad Hoc网络多跳特性,并对网络吞吐量、延时和冲突概率有明显地改善,性能优于经典的二进制指数退避(BEB)算法.

An Adaptive Backoff Algorithm for Ad Hoc Network Based on Transmission State

An adaptive backoff algorithm based on transmission state(ABTS) for Ad Hoc network is proposed.Used with ABTS,the channel status is sensed by calculating amount of competitive nodes locally and the contention window is adjusted linearly or multiplicatively according to different channel status.To reduce data losses,ABTS algorithm gives frames retransmitted repeatedly higher priority to send.Experiment demonstrates that ABTS algorithm has suitable performances in multi-hop Ad Hoc network,and,compared to Binary Exponential Backoff algorithm,ABTS algorithm has better performances in term of throughput,end-to-end delay and collision rate.