Opportunistic AODV routing protocol for cognitive radio wireless sensor networks

The two major concerns of the wireless communication system are throughput of the network and underutilization of wireless channels. Opportunistic routing (OR) aims at improving the former and coping with the latter. Due to the unreliable characteristics of such channels, traditional routing achieves poor throughput. Since traditional routing arbitrarily selects high lossy links among diverse paths of same minimum length. This paper focuses on designing a multipath, multichannel opportunistic ad-hoc on demand distance vector routing protocol that uses shortest distance as well as expected transmissions count (ETX) as a parameter to choose the next forwarding node and the most reliable link respectively. The conventional AODV uses hop count for the selection of route in the network. In this paper it is proposed to harvest the advantage of OR with AODV for cognitive radio wireless sensor networks (CRWSN) to improve its efficiency. The ETX is computed based on the quantized value of RSSI of the links. Using ETX the reliable link is computed and stored in routing table. The packets are forwarded to the destination using the next hop and channel details available in the routing table. The routing parameters such as capacity, spectrum occupancy, throughput, and packet delivery ratio (PDR) are evaluated. Simulation result shows that opportunistic AODV protocol yields increased PDR (7%) than traditional AODV in the presence of two interferers.