Contention Window and Transmission Opportunity Adaptation for Dense IEEE 802.11 WLAN Based on Loss Differentiation

In high density (HD) WLANs, packet losses can occur due to hidden terminals (asynchronous interference) or collisions (synchronous interference). Without differentiating above packet losses, the standard backoff algorithm of IEEE 802.11 with binary exponential backoff (BEB) can greatly degrade throughput and fairness. In this work, we exploit differentiated PER (packet error rate) to propose a novel CWTO (joint contention window and transmission opportunity) adaptation algorithm to improve the aggregate throughput as well as network fairness for multi-cell HD WLANs. Contention window and transmission opportunity adaptation are dedicated to throughput maximization and fairness provision respectively and their effectiveness supported by extensive simulation results.