Scalable limited channel feedback for downlink coordinated multi-cell transmission

It is well known that coordinated multi-cell transmission in downlink (DL) is a promising technique to significantly increase the system throughput and cell-edge user throughput. In this paper, we propose a scalable two-stage channel feedback mechanism not only to support downlink single-cell multi-user MIMO (MU-MIMO), but also to efficiently support multi-cell coordination. This scheme yields remarkable system performance improvements with considerable uplink (UL) feedback overhead, and also has good backward compatibility for single-cell transmission scheme. 1