A QoS constrained cognitive routing algorithm for ad hoc networks based on directional antenna

Communication and networking with directional antenna are widely used recently. In this paper, for the communication scenarios based on the directional antenna, we design a cognitive retransmission mechanism. The mechanism can increase the probability of successful retransmission on one hand, on the other hand, it can dramatically reduce the route discovery time in ad hoc networks. For factual applications, we propose a QoS-constrained cognitive routing algorithm named as QoS CRA for wireless ad hoc networks. This algorithm adopts the strategy of initiating the route discovery by the source node, but making decision to choose the best route by the destination node. The simulation results demonstrate that the cognitive retransmit strategy is far more efficient than the traditional one and different QoS parameters in our algorithm can meet different application requirements.