A Threshold-Based Relay Switching Protocol for Enhanced Capacity and Resource Efficiency

This letter deals with the issue of inefficient use of radio resources due to frequent relay switchings in overhead constrained cooperative relay networks. A threshold-based relay switching protocol is proposed for enhanced achievable capacity and efficient resource management while preventing frequent switchings. We derive the achievable capacity under fading channels based on switching probability and ergodic capacity analysis. Also, the optimal threshold value is obtained from a convex optimization problem. Numerical and simulation results reveal the advantage of the proposed protocol over the conventional opportunistic relay selection protocols.