An Opportunistic Routing Protocol based on Link Quality and Local Topology in Mobile Ad hoc Networks

In mobile ad hoc networks (MANETs), the frequent changes of network topology due to node mobility increases the cost of maintaining deterministic routing. As one state-less routing protocol, opportunistic routing utilizes the nature of broadcast and does not have to maintain deterministic routes. However, broadcast may cause interference to some nodes and affect the transmission quality between nodes. Thus, how to adapt opportunistic routing to the dynamic environment and avoid unreliable transmissions are two important issues to solve. In this paper, we propose an opportunistic routing protocol based on link quality and local topology (OR-LqT) in MANETs. In the protocol, we measure link qualities by considering both interference and nodes' mobility to find the candidate set, and select a next forwarding node by prioritizing the neighbor nodes based on their locations, local topology and moving adaptivity. The proposed OR-LqT can avoid the number of unreliable transmissions and the number of dead-ends. The performance results show that compared to the conventional routing protocols, such as AODV, $\mathbf{PRR}^{\ast}\mathbf{d}$ and GPSR, the OR-LqT decreases the number of dead-ends by more than 33.5%, packet drop ratio by more than 21%, average delay by more than 22% and overhead by more than 21%.