关键词: 无线局域网, 多输入多输出系统, 帧聚合, 性能优化, 链路质量判据, 跨层设计

Abstract:

In order to meet the requirements of the next-generation wireless LAN,an optimization algorithm of frame aggregation is proposed for the multiple-input multiple-output ( MIMO) system. In this algorithm,first,the bit error rates ( BERs) in different spatial streams and modulation /coding schemas are calculated. Next,the frame aggregation throughput under saturated traffic is analyzed by integrating the Markov chain model that describes the
contention access process of channel. Then,the optimization algorithm which tunes the parameters such as the aggregated size dynamically under current channel and collision conditions is presented. Finally,the algorithm is implemented based on the link quality metric using a simplified method. Analytical and simulated results show that,with the help of the diversity of MIMO technology,the proposed algorithm helps to select optimal control parameters in real time,improves the network throughput,reduces the BER and greatly decreases the complexity of the system to meet the requirements of real-time control.

Key words: wireless LAN, multiple-input multiple-output system, frame aggregation, performance optimization, link quality metric, cross-layer design