Wireless space network coding for cooperative communications

Network-coded cooperation techniques endow Network Coding (NC) capability with the relay to reduce time slots overhead for multi-session Cooperative Communications (CC). However, recent results have shown that employing NC may have an adverse effect and diminish the advantage of NC in CC due to the existence of NC noise. In this paper, we propose Space Network-Coded Cooperation (SNCC) in which sources transmit in turn, and relay terminals overhear and process the data they have received from different sources. Then, they broadcast the coded data to corresponding destinations in a single time instance. In this spirit, NC can be viewed as being performed in the space, and each destination can average NC noises that come from different relays. We derive a closed-form expression for the NC noise of SNCC, and show that SNCC has a potential to significantly reduced the NC noise compared with the traditional scheme. Consequently, SNCC is able to take more advantage of NC in CC. Finally, numerical simulations have been constructed to illustrate its performance.