Inter-Relay Traffic through Network Coding in Cooperative Wireless Ad Hoc Networks

Abstract

Cooperative Network-Coded Hybrid ARQ (Coop-NC HARQ) has recently been proposed as a smart way to improve Decode & Forward (D&F) relaying. According to this idea, cooperators send HARQ redundancy on behalf of a source coded together with a data packet intended for the destination they are helping and taken from their own queue. This paper applies for the first time such a technique in ad hoc networks with Multi-User Detection (MUD) capabilities, allowing several terminals to simultaneously act as relays. In this context, we introduce a novel communication paradigm that leverages network-coded retransmissions to allow more efficient data exchanges among all terminals involved in a cooperative process, enabling interrelay communications as well. Simulation results show that the proposed solution offers important gains over D&F as well as Coop-NC HARQ in both single- and multi-hop networks in terms of throughput and energy consumption.