Routing improvement using directional antennas in mobile ad hoc networks

In this paper, we present the initial design and evaluation of two techniques for routing improvement using directional antennas in mobile ad hoc networks. First, we use directional antennas to bridge permanent network partitions by adaptively transmitting selected packets over a longer distance, still transmitting most packets a shorter distance. Second, in a network without permanent partitions, we use directional antennas to repair routes in use, when an intermediate node moves out of wireless transmission range along the route; by using the capability of a directional antenna to transmit packets over a longer distance, we bridge the route breakage caused by the intermediate node´s movement, thus reducing packet delivery latency. Through simulations, we demonstrate the effectiveness of our design in the context of the dynamic source routing protocol (DSR).