A Capacity Achieving Precoding Scheme Based on Partial Channel Information for Broadcast MIMO Systems

This paper presents a zero-forcing algorithm based on the partial channel knowledge to select the best users for transmission without causing interference to others in a broadcast MIMO system. The proposed scheme preserves the optimal achievable ergodic sum capacity of zero-forcing techniques in limit of large number of active users with significant reduction in complexity and feedback load for channel information updates. Both analytical and simulation results on its advantages in feedback load, complexity and achievable sum rate are presented in different scenarios.