关键词: 无线局域网络, 分布式协调机制, 指数退避算法, 饱和吞吐量

Abstract: DCF is the main network protocol of accessing other mobile stations for nodes in ad hoc networks.It is necessary to provide each station with a self-controlling method，called the backoff algorithm.In this article，two changes of exponential backoff algorithm for DCF has been made.In order to test its validity，it is modeled with a discrete time Markov-chain，then its saturation throughput is measured and evaluated under several conditions and several sets of parameters which are to be adjusted according to the network condition，with the aim of approaching maximum throughput when stations are saturated.

Key words: wireless local area network, distributed coordination function, exponential backoff algorithms, saturation throughput