Relay subset selection in wireless networks using partial decode-and-forward transmission

This paper considers the problem of selecting a set of relay nodes to assist a transmitting node in a two-hop wireless network. Through put-maximizing relay subset selection is a difficult problem that depends on variables such as node locations and power constraints. It is proposed that all relays employ partial decode-and-forward operations to improve the tractability of the relay selection problem. This allows relay selection to be transformed into a simpler relay placement problem which motivates two proximity-based relay selection algorithms. These algorithms are compared with a greedy algorithm based on relay channel gains to the sink and an algorithm that randomly selects relays. The diversity gain achieved by employing multiple relay nodes is derived. The proposed proximity-based algorithms offer good performance in terms of the expected achieved rate.