QOS constrained routing algorithm using directional antenna

Directional antenna provides tremendous performance improvement in an ad hoc network. There are many applications such as multimedia and real time, which requires guaranteed QoS (quality of service) in the network. In this paper, we present QoS routing algorithm which finds a optimal path from source to destination as well as for other nodes in the network. Route discovery is initiated by source node and routing path is selected based on routing metric value which is having delay and bandwidth as constraints. The probability updation rule is used to increase the probability of beam in the direction of successful transmission and it reduces the routing overhead in retransmission. The simulation results demonstrate the routing overhead which reduces as the number of iteration increases. It shows significant improvement in terms of average routing overhead with directional transmission over omnidirectional transmission.