Statistical Priority Control for Ad Hoc Networks with Different Communication Ranges

Abstract

In the IEEE 802.11e MAC protocol, the Enhanced Distributed Channel Access (EDCA) was issued to support the quality of service (QoS) for the different categories of traffic. However, the performance will deteriorate rapidly when the network is overloaded, and the QoS required by real-time services cannot be guaranteed. In this paper, we first derive a Markov chain model to analyze the performance of the EDCA at different transmission distances. Then, we propose a dynamic access threshold-based MAC protocol that supports working at different transmission distances, called DAT-EDCA, with the goal of improving access performance when the network is overloaded. The ns3 simulation results show that the DAT-EDCA can significantly improve throughput and reduce access delay when the network is overloaded, while QoS is also guaranteed. The protocol can be seamlessly integrable with the EDCA and works without APs which has guiding significance for the design of the Ad Hoc network MAC protocol.