<FONT face=Verdana>A high-efficient coded cooperative scheme based on bit-interleaved coded modulation is proposed. Encoded bits of the cooperative user are partitioned into two frames

bit interleaved

mapped and then transmitted on the allocated time slots respectively. Bit interleaver is utilized to satisfy the fading coefficients of the different bits of a same symbol cound be modeled as i.i.d variables. One hand

the pairwire error probability over various fading channels is derived

and an upper-bound on bit-error probability is presented. Both theory analysis and simulations show that the BICM CC with high-order constellations can also achieve the full diversity under quai-static Rayleigh fading channels

whereas no any cooperation diversity over fast fading channels. On the other hand

labeling maps and interleavers are studied. It can be concluded that GRAY labeling is still optimum for the cooperative users and different interleavers of two frames can improve the performance.