A Novel Multi-channel MAC Protocol for Directional Antennas in Ad Hoc Networks

Abstract

In recent years, the employment of directional antennas in ad hoc networks has increased significantly. In this paper, we propose a multi-channel MAC protocol for directional antennas (MCMDA) for IEEE 802.11 based ad hoc networks. To improve the network performance, the so-called hidden terminals and deafness should be decreased as much as possible. In MCMDA, not only multiple channels are effectively utilized but also vertically opposite clear-to-send is employed to minimize the effects of hidden terminals and deafness. Each node is equipped with multiple interfaces for multiple directional antennas such that concurrent transmissions and receptions take place in a node at the same time, resulting in further improvement of the network capacity. The performance study based on extensive computer simulation shows that the proposed MCMDA achieves significant performance improvement in comparison to the conventional directional MAC as well as IEEE 802.11 distributed coordination function in terms of network throughput and end-to-end delay.