Selection Relaying at Low Signal to Noise Ratios

TL;DR

This paper investigates the performance of selection relaying schemes at low SNRs, emphasizing energy transfer and proposing an energy-optimized SDF approach to improve outage probability.

Contribution

It introduces an energy optimization scheme for selection decode and forward relaying at low SNRs, enhancing outage performance beyond existing methods.

Findings

Selection relaying improves outage probability at low SNRs.

Energy optimization further reduces outage probability.

Proposed scheme approaches the max-flow min-cut bound.

Abstract

Performance of cooperative diversity schemes at Low Signal to Noise Ratios (LSNR) was recently studied by Avestimehr et. al. [1] who emphasized the importance of diversity gain over multiplexing gain at low SNRs. It has also been pointed out that continuous energy transfer to the channel is necessary for achieving the max-flow min-cut bound at LSNR. Motivated by this we propose the use of Selection Decode and Forward (SDF) at LSNR and analyze its performance in terms of the outage probability. We also propose an energy optimization scheme which further brings down the outage probability.