A SINR Threshold-Based Limited Feedback and Feedback Load Analysis for Downlink Multiuser Diversity

We propose a feedback strategy based on SINR threshold for downlink multiuser wireless systems. By using the proposed strategy the base station receives feedback only from those users whose SINRs are above a threshold which is elaborately chosen and broadcast to all users in the cell by the base station. So not all users need send their channel direction information (CDI) and channel quality information (CQI) to the base station. It is proved that downlink wireless systems using the proposed strategy can achieve the multiplexing diversity and multiuser diversity gain with greatly reduced the sum feedback rate.