<FONT face=Verdana>We propose a kind of simple-encoding irregular systematic LDPC codes suitable for relay cooperation. The constructed double LDPC codes are then applied to one-relay cooperation. The authors also suggest a new joint iterative decoding algorithm performed at the destination node for multiple received signals based on the joint Tanner graph for the double LDPC codes. It is demonstrated by theoretical analysis and numerical simulations that the proposed approach can

<FONT face=Verdana>well combine the techniques of high-efficiency channel coding and cooperation to fully achieve the potential gains from coding and diversity

which consequently leads to the significant performance improvement over the non-cooperation system under the same conditions.