An adaptive MAC protocol for wireless ad hoc community network (WACNet) using electronically steerable passive array radiator antenna

In the context of ad hoc networks, use of directional antennas can largely reduce the radio interference, thereby improving the utilization of wireless medium and consequently the network throughput. However, in order to fully exploit the capability of directional antennas, whenever a source and a destination engage in a communication, all the neighbors of source and destination nodes should know the direction of communication so that they can initiate new communication in other directions, thus preventing interference with on-going data communication. In our adaptive MAC protocol, each node keeps certain neighborhood information dynamically so that each node can keep a track of the direction of communication events going on in its neighborhood at that instant of time. Moreover, appropriate mechanisms for null steering of directional antennas in user terminals can help exchange the neighborhood information in the presence of on-going communication and can drastically improve the medium utilization through overlapping communications in different directions.