Energy-Efficient Path Selection Using SNR Correlation for Wireless Multi-Hop Cooperative Communications

• Main Authors: In-Ho Lee, Haejoon Jung
• Format: Article
• Language: English
• Published: MDPI AG 2018-11-01
• Series: Energies
• Subjects: multi-hop decode-and-forward relaying; limited channel feedback; SNR correlation; relay selection; Nakagami fading channels
• Online Access: https://www.mdpi.com/1996-1073/11/11/3004

In this paper, we consider partial path selection (PPS) for a multi-hop decode-and-forward cooperative system with limited channel state information (CSI) feedback, where the PPS utilizes local CSI only for a subset of hops on each of all independent paths between a source and a destination to reduce the energy consumption for CSI feedback. To enhance the end-to-end performance of the PPS, we propose a novel PPS method with local CSI chosen by the correlation between the end-to-end signal-to-noise ratios (SNRs) based on global and local CSI under Nakagami-<i>m</i> fading channels. For each path, we pick a subset of hops to report CSI with the highest correlation for a given CSI feedback overhead requirement, which can achieve the similar end-to-end outage probability to the best path selection with global CSI. We provide an exact and closed-form expression for the SNR correlation coefficient and present an impact of the SNR correlation on the end-to-end outage probability.