Optimal Location of Feedback Handler under Receiver Contention Schemes for Routing in Wireless Networks

Due to the broadcast and error prone nature of wireless medium, novel routing mechanisms based on receiver contention have been proposed recently. The intuition of this strategy is, transmitters make routing decisions based on contentions of nodes that have successful reception. A remarkable advantage of receiver contention is the long average advancement of transmissions. To the best our knowledge, existing works utilizing receiver contention schemes are all based on a common assumption. That is, feedback packets sent by contending nodes are all destined to the transmitters. However, probability of reception is a function of distance. The longer the distance is, the lower the reception probability will be. According to this relation, we argue that transmitters may not be the best nodes to taking care of contention packets. In this paper, we consider uniformly distributed sensor networks, and propose the optimal locations, in terms of maximizing the expected advancement of each transmission, to place nodes which are responsible for handling feedback packets. We call these nodes feedback handlers. Based on the simulation results, placing the feedback handlers on the optimal locations can raise expected advancement up to about 30 percent, comparing to existing works.