A Cluster-Based Multiuser Cooperative Network

A novel cluster-based coherent Multi-User (MU) relaying system is proposed, where a number of source/destination pairs communicate concurrently over the same physical channel and a set of amplify-and-forward relays assist them. A secondary short-range wireless system with single/multi-hop unicast or broadcast ability is considered for the Channel State Information (CSI) dissemination. To reduce the CSI dissemination overhead, the relays are grouped in several independent clusters. Distributed diversity gain is attained at the destinations by applying phase rotations between clusters. The CSI dissemination is analyzed thoroughly, and compared with that of previous works on MU relaying.