Improving Network Capacity by Delegate Polling Hybrid Access Protocol in Non-Infrastructure WLANs

In non-infrastructure WLANs low network capacity and lack of QoS guarantee are the bottlenecks of commonly used contention access protocols. In this paper, we proposed a novel MAC protocol, the Delegate Polling Hybrid Access (DPHA) ¹protocol, which uses a distributed polling-based access scheme, delegate polling access scheme, to avoid collisions and adopt contention access scheme as a complement when wrong polling decisions occur. We designed a feasible delegate polling access scheme in non-infrastructure networks, which lets the current transmitting Traffic Stream (TS) delegate the AP to select the next transmitting TS based on a polling algorithm and announce it in the data packet header. The elaborately designed polling algorithm employs conditional service differentiation to improve fairness for best effort traffics and overcomes the drawbacks of existing polling algorithms. Simulation results demonstrate that DPHA protocol can significantly improve network capacity and QoS performance for all kinds of traffics.