2012/10/01 by Vijayvaradharaj T. Muralidharan, Muralidharan, Vijayvaradharaj T., B. Sundar Rajan +1 · 1 citation
Computer Science · Engineering · Mathematics · #Advanced Wireless Communication Technologies #Cooperative Communication and Network Coding #FOS: Computer and information sciences #Information Theory (cs.IT) #Wireless Communication Security Techniques #cs.IT #math.IT
paper · pdf · doi:10.48550/arxiv.1210.0490
10 pages, 5 figures
openalex publication_date 2012/10/01 · arxiv created 2012/10/19 · arxiv updated 2012/10/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We consider the two user wireless Multiple Access Relay Channel (MARC), in which nodes A and B want to transmit messages to a destination node D with the help of a relay node R. For the MARC, Wang and Giannakis proposed a Complex Field Network Coding (CFNC) scheme. As an alternative, we propose a scheme based on Physical layer Network Coding (PNC), which has so far been studied widely only in the context of two-way relaying. For the proposed PNC scheme, transmission takes place in two phases: (i) Phase 1 during which A and B simultaneously transmit and, R and D receive, (ii) Phase 2 during which A, B and R simultaneously transmit to D. At the end of Phase 1, R decodes the messages xA of A and xB of B, and during Phase 2 transmits f(xA,xB), where f is many-to-one. Communication protocols in which the relay node decodes are prone to loss of diversity order, due to error propagation from the relay node. To counter this, we propose a novel decoder which takes into account the possibility of an error event at R, without having any knowledge about the links from A to R and B to R. It is shown that if certain parameters are chosen properly and if the map f satisfies a condition called exclusive law, the proposed decoder offers the maximum diversity order of two. Also, it is shown that for a proper choice of the parameters, the proposed decoder admits fast decoding, with the same decoding complexity order as that of the CFNC scheme. Simulation results indicate that the proposed PNC scheme performs better than the CFNC scheme.