A self-adaptive minimum contention window adjusting backoff algorithm in IEEE 802.11 DCF

With the popularity of smart electronic products, wireless network, such as WLAN in particular is facing huge challenges in capacity, etc. In this work, we introduce a simple but extremely accurate, analytical Markov chain model on the IEEE802.11 DCF backoff procedure and find that the maximum saturation throughput of the current network is directly related to the number of competition station. What´s more, the DCF is actually a static protocol that cannot adjust itself to the changing network environment. This paper proposes a self-adaptive minimum contention window adjusting (SMCWA) backoff algorithm to get maximum saturation throughput by flexibly adjusting the minimum contention window of DCF based on the number of competition station in the network. Moreover the simulation result shows that SMCWA also improves other aspects of network performance significantly.