Cooperative Signal Constellation for LDPC-Coded Relay System

In this letter, we first develop the cooperative constellation design for the single relay LDPC-coded system; then we describe the associated iterative detection/decoding scheme at the destination node. Simulation results show that, with the cooperative constellation and an appropriate power allocation strategy, the relay system can achieve a performance gain of about 1.6 dB around BER = 10
^-4
.