【摘要】 目前,无线局域网(WLAN)中的媒体接入控制层(MAC)广泛采用基于IEEE802.11的二进制指数回退算法(BEB)的DCF协议。当WLAN中的节点数目迅速增加时,该协议存在系统吞吐量会急剧降低,网络性能变差的缺点。详细分析了无线局域网中IEEE802.11MAC层的二进制退避协议,指出原协议在进行冲突处理上的不足,并结合树型分解算法(TSA)和快速分解算法(FCR),提出一种改进的树型冲突分解算法(ITSA)。并用MATLAB仿真了CSMA/CA协议和ITSA算法。分析和仿真结果证明,与IEEE802.11等协议采用的二进制指数退避算法相比,该算法能较大的提高系统吞吐量。更多还原

【Abstract】 At present, Medium Access Control(MAC) in Wireless Lan(WLAN) widely uses DCF protocols of Binary Exponential Backoff(BEB) algorithm based on IEEE802.11. If the number of competing stations grows rapidly, the system throughput and network capacity will decrease sharply. This paper analyzes BEB algorithm in IEEE 802.11 MAC layer in detail, then points out the shortage of collision disposal of former protocols. Based on Tree-Shaped Arithmetic(TSA) and Fast Collision Arithmetic(FCA), a kind of improved collision disposal arithmetic is presented, which is called Improved Tree-Shaped Arithmetic(ITSA). For further research, CSMA/CA protocols and ITSA are imitated by MATLAB. Analysis and imitation results show that, compared with BEB algorithm and other algorithms, ITSA can improve system throughput greatly.更多还原