Optimization of antenna beam pattern in ad hoc networks for optimal global performance

Directional antennas shape transmission patterns to provide greater coverage distance and reduced coverage angle. When used in an ad-hoc network, this reduces interference among transmitting nodes and thereby increases throughput. A problem that has not been addressed is how to compute individual beam patterns that maximize some measure of global network performance. Historically, the focus has been on finding node antenna patterns that give locally optimal performance. In this paper we investigate a low hardware complexity beamforming approach aimed at improving global performance. Given a multi-hop route from source to destination, beam patterns are shaped to maximize average signal-to-noise ratio across all nodes on the route, which reduces bit-error rates and extends battery and network lifetime. By using phase-only weights, hardware costs are minimized.