WSN13-3: Path Shortening for Delivery Rate Enhancement in Geographical Routing via Channel Listening

Geographical routing protocols are promising in wireless sensor networks because of their ability to discover a sub-optimal route without the help of a global state. Existing geographical routing protocols can guarantee packet delivery if the network topology after planarization remains connected. However, face routing used in non-flooding geographical routing algorithms usually results in a large number of hops, which not only reduces network efficiency, but may also decrease delivery rate when packets are subject to the constraint of time to live (TTL). In this paper, we present a path shortening algorithm that reduces the number of hops of geographical routing by exploiting the channel listening capability of wireless nodes. We investigate the impact of the algorithm on the delivery rate under the constraint of TTL. Simulation results show that in average the path shortening algorithm can reduce as much as 80% hops on the routes obtained by existing geographical protocols such as GPSR and GOAFR⁺ in a critical network density region, and the improvement of packet delivery rate is up to 50% with a maximum of three retransmissions without increasing TTL.