Design and Implementation of Distributed Cognitive Medium Access Control Protocol for Multi-hop Mobile Ad Hoc Network with Single Transceiver

摘要

Recently, cognitive medium access control (MAC) protocol has played a dominant role in mobile ad hoc network (MANET). However, existing algorithms ignore mobility, multihop nature and channel selection fairness. Thus extension of them becomes a critical issue. In this paper, we attempt to address the improvement of these shortages based on power saving mode (PSM) by redesinging channel sensing and data transmission for nodes deployed with a single transceiver. The contribution of this paper is threefold. First, we present the flowchart of proposed model with announcement traffic indication message (ATIM) and DATA window, resulting in separation of control channel and data channel in time field. To realize it, three types of channel information as state, maintenance time and selection priority are raised, based on which channel sensing, information sharing and channel sorting are realized. Second, we realize channel sensing and state sharing through redefinition and cooperation of control packets to record channel state, idle or busy. Third, we propose multi-hop cooperation, channel state updating/changing and reservation mechanisms to exchange packets, guaranteeing that channel would be used fairly and balanced. Simulation results show that, not only throughput and channel utilization are improved as well as acceptable value of channel vacate time (CVT) and channel opening time (COT), but also multi-hop, mobility and fairness nature are taken into account, which meets the need of MANET.