SER Performance Analysis for Jointing Network Coding and Space Time Codes in DF Relay System

In this paper, a new joint coding scheme that combine the network coding and the conditional distributed space-time codes was proposed in decode-and-forward (DF) wireless relay network. Symbol-error-rate (SER) performance of proposed scheme was analyzed. Based on studying the SER of the traditional distributed space time in three relays system, the SER closed-form and upper-bounds expression of scheme were derived. In our systems, three relays were considered. Two relays were operated as the space time codes, and one relay was used as the simple network coding. The theoretical analysis proved that proposed joint coding scheme had better performance of SER than traditional space time codes in DF relay system. The numerical results shown that our scheme had the lower SER compared with traditional distributed space time codes.