Abstract: A linear auto regressive (AR) model channel prediction technique is proposed to enhance the performance of auto rate selection mechanism in IEEE 802.11, and eliminate the delay effect between measurement of received signal strength (RSS) values and rate selection for the immediate frame transmission. The best rate is selected based on the data payload length, frame retry count and the RSS value estimated from recorded values.The estimation step-size is analyzed and the proposed mechanism is simulated in TwoRayGround and Ricean channel models in the NS2 environment.Simulation results show that the proposed mechanism enhances mean throughput performance of IEEE 802.11 system compared with that presented in the literature.In saturation, the enhancement reaches 7%, and under a finite load condition, the enhancement reaches 30%.

Key words: wireless LAN, rate selection, channel estimation, AR model, throughput