Outage Performance of DF Network Coded (DFNC) Multi-User Cooperative Diversity in Orthogonal Uplink Channels

Abstract

In this paper, we propose a Decode-and-Forward Network Coded (DFNC) multi-user cooperation scheme for orthogonal uplink channels in a wireless network. The network consists of m peers having independent information transmitting to a common destination. Each peer transmits its own data in the first time phase and serves as a relay in the second time phase to transmit the network coded information combining its own and others. Assuming block fading with independent fading coefficients, we evaluate the outage probability performance of the proposed scheme using high-SNR approximation. Particularly, we develop an upper bound on outage probability of DFNC, and compare it with Space-Time-Coded (STC) cooperation protocol and Repetition-based (REP) cooperation protocol. From theoretical analysis and numerical results, we show that the outage performance of proposed scheme outperforms both STC and REP at least in high-SNR region, regardless of total number of cooperating peers and provides diversity order of m + 1 in contrast with diversity order of m provided by STC and REP.