Measurement-based link scheduling for maritime mesh networks with directional antennas

The proliferation of wireless transceivers and the availability of unlicensed band has given a boost to the deployment of wireless networks, with IEEE802.11/WiFi being the major driver in this arena. In this research, we consider a wireless mesh network designed for long distance communication with a typical deployment scenario of a maritime mesh network. This network uses an antenna system made up of multiple fixed-beamwidth antennas. Compared to most other directional antenna schemes which use directional antenna for transmission and omnidirectional antenna for reception, our system uses directional antennas for both transmission and reception where a pair of transmitter-receiver antennas need to be aligned and have an acceptable channel quality before transmission can take place. Through efficient use of directional antennas for both transmission and reception, and spatial reuse in transmission, we are able to realize a high capacity mesh network. In this paper, we present a practical approach to achieve contention-free medium access, namely, a measurement-based link scheduling algorithm. We evaluate the performance of the link scheduling algorithm using simulations and show that it is able to exploit the spatial diversity provided by the directional antennas to outperform comparable schemes for wireless mesh networks. We also briefly discuss implementation issues to demonstrate the viability of the approach. Copyright c © 2008 John Wiley & Sons, Ltd.