A CSMA/CA Optimization Algorithm Based on Priority in ZigBee Network
SHI Jiachuan;LIU Jianfei;QIN Hao;WANG Mengjun;School of Electronic and Information Engineering,Hebei University of Technology;
The CSMA/CA is the core algorithm in MAC layer for ZigBee,which can't provide priority service and has poor performance in high load network. A new scheme is proposed,including that the priorities of different services can be rated by setting the contention window according to network load states,meanwhile,the backoff exponent of the algorithm can be adjusted adaptively with network load. The network model of the proposed algorithm is constructed by means of Markov chain model and simulated by NS2. The simulation results show that the network throughput capacity is improved and the packet loss rate is reduced,obviously,the overall performance of the network is optimized with a little time delay increasing.