Relay selection for peer-to-peer cooperative OFDMA with channel distribution uncertainty

Abstract

Peer-to-peer relay technique provides the opportunity of cooperative communication between users to achieve the transmission diversity. In this paper, the problem of relay selection and subcarrier allocation in peer-to-peer cooperative OFDMA system with channel distribution uncertainty is studied. The quality of service (QoS) requirements are characterized with the probabilistic constraints. The Kullback-Leibler (KL) divergence is adopted to describe the uncertainty of the channel state information (CSI), which follows a distribution deviated within a certain distance from the reference distribution. Since the probabilistic constraint is intractable, we resort to a tractable upper bound instead. The problem is solved by the interior point cutting plane (IPCP) method, which proceeds in round whereby an iterative method is designed to combine both golden section method and interior point method to find the saddle point of the constraint. Simulation results show the effectiveness of our algorithm.