Energy Efficient Opportunistic Routing in Wireless Networks

Opportunistic routing [1, 2] was shown to improve the network throughput greatly. The core idea is to allow any node in the forwarder list, which overhears the transmission and is closer to the destination to participate in forwarding the packet. The nodes in forwarder list are prioritized and the lower priority forwarder will discard the packet if it has been forwarded by a higher priority forwarder. One open problem is how to select and prioritize forwarder list efficiently. In the paper, we investigate how to select and prioritize forwarder list to minimize energy consumptions. We study the case where the transmission power of each node is fixed (known as non-adjustable transmission model) as well as the case where each node is able to adjust its transmission power for each transmission (known as adjustable transmission model). Energy optimum algorithms to select and prioritize forwarder list in both cases are presented and analyzed. Worth to mention that, our methods do not assume any geometrical properties or energy models, they apply to practical and dynamic wireless networks. In addition, we conducted extensive simulations in TOSSIM to study the performance of the proposed routing protocol by comparing it with ExOR [1].