Distributed Relay-Assignment Protocols for Coverage Expansion in Cooperative Wireless Networks

—One important application of cooperative communications is to extend coverage area in wireless networks without increasing infrastructure. However, a crucial challenge in implementing cooperation protocols is how to select relay-source pairs. In this paper, we address this problem based on the knowledge of the users’ spatial distribution which determines the channel statistics. We consider two scenarios at the destination node, when the receiver uses MRC and when no-MRC is used. First, we characterize the optimal relay location to minimize the outage probability. Then, we propose and analyze the performance of two schemes: a distributed nearest neighbor relay assignment in which users can act as relays, and an infrastructure-based relay-assignment protocol in which fixed relay nodes are deployed in the network to help the users forward their data. The outage probabilities of these two schemes are derived. We also derive universal lower bounds on the performance of relay-assignment...

• Type: Journal
• Year: 2010
• Where: TMC
• Authors: Ahmed K. Sadek, Zhu Han, K. J. Ray Liu
• Keywords: Coverage Area, Outage Probability, Relay-assignment Protocols, TMC 2010