Joint Virtual MIMO and Network Coding Scheme with Superposition ARQ in Relay System

Abstract

A new two-way transmission protocol termed VMNC-SARQ (Virtual MIMO Network Coding with Superposition ARQ) was proposed in this paper, which could improve throughput efficiency of DF (Decode-and Forward) relay network signally. In first step, two single-antenna nodes send messages to the double-antenna relay station simultaneously by using a method similar to 2×2 VBLAST (Vertical Bell Laboratories Layered Space Time) system. In step two, relay station processes the decoded signals received from two source nodes through Network Coding, and then broadcasts the combined messages with Alamouti Coding. A novel retransmission strategy will be implemented when demodulation and decoding failure presents. In order to reduce retransmission overhead, we attach the retransmitted packet to the latter normal packet by using higher modulation, and exploit the confidence value of previously error packet to help to recover both packets. Theoretical analysis and simulation results show that the proposed scheme could greatly improve end-to-end throughput efficiency for two-way relaying systems

DOI : http://dx.doi.org/10.11591/telkomnika.v12i2.3444