Optimised Constellation Prerotation for 3-Terminal 1-Relay Network with Wireless Network Coding

• Published in: IEEE communications letters 2012-08, Vol.16 (8), p.1200-1203
• Main Authors: Hekrdla, Miroslav, Sykora, Jan
• Format: Article
• Language: English
• Subjects: Access methods and protocols, osi model; Applied sciences; Binary phase shift keying; Encoding; Exact sciences and technology; Network coding; Network topology; Organization and planning of networks (techniques and equipments); precoding design; Relays; Switching and signalling; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Teleprocessing networks. Isdn; Transmission and modulation (techniques and equipments); Wireless network coding; Wireless networks
• ISSN: 1089-7798; 1558-2558
• DOI: 10.1109/LCOMM.2012.060812.120427

Wireless (Physical-Layer) Network Coding (WNC) is an interference harnessing physical-layer concept combining network coding principles and broadcast nature of the wireless medium. Significant capacity gains of WNC were shown in a wireless 2-Way Relay Channel (2-WRC). Extension of WNC to more complicated network topologies potentially offers even larger gains than in the 2-WRC. However, such an extension is generally non-trivial. In this paper, we show that it is feasible to achieve additional considerable capacity gains in comparison to bidirectional relaying approach in a three-terminal one-relay network. We focus on the constellation design for its uplink (Multiple Access Channel (MAC) stage). The throughput maximisation is achieved by an optimised prerotation of source constellations, effectively reducing a number of required MAC stages.