Distributed Relay Selection Scheme in Decode-and-Forward Cooperative Systems

Conventional cooperative relaying schemes usually process the network CSI in a centralized way by setting one central node where decisions, such as relay selection, are made by relying on information from all channels. In this paper, we propose a novel distributed relay selection scheme for Decode-and- Forward networks. In this scheme, each relay decides to participate in cooperation based on link status of its own, thereby eliminating the need for relay coordination. Outage performance of the proposed distributed system is then investigated and general results applicable to an arbitrary number of relays are provided in closed-form.