CTH12-6: Analysis Techniques for Coded Modulation Based Cooperation Protocols
Santosh V. Nagaraj, Mark R. Bell · Globecom · 2006
Recently, a coded modulation (CM) protocol was proposed for user cooperation diversity in wireless networks. The protocol was based on jointly encoding the data from all cooperating users into one code sequence. In this paper, further results relating to CM protocols are provided, including code analysis techniques. It is shown that tighter bounds are possible by merging a few successive trellis stages into a single bigger trellis with parallel transitions. Cooperation protocols depend critically on the performance over the channel between the cooperating users. Two adaptations of the CM protocol are shown that ensure robustness of the protocol for errors on the channel between the users. The single CM code is used in place of error correction codes anyway used by each user. So, CM based cooperation does not involve further constellation expansion. Hence, it is suitable for high spectral efficiencies also.