ABSTRACT We study the linear precoder design problem in downlink multiuser MIMO (MU-MIMO). We first analyze the leakage-based precoder design under a full multiplexing constraint, which maximizes the signal-to-leakage-and-noise ratio (SLNR) for each individual user. We prove that the SLNR-optimal multistream precoder always maximizes the SLNR via essentially concentrating all the available transmit power on a single data stream, regardless of the rank constraint. We then propose a novel design criterion, called signal-over-leakage capacity (SLC), which corresponds to the achievable rate difference between a virtual signal-only link and a virtual interference-only link, for each individual user. We completely solve the SLC maximization problem and provide a closed-form optimal solution, which distributes the transmit power among multiple data streams, and thus better utilizes the available spatial degrees of freedom in an MU-MIMO system. Numerical experimental results are provided to corroborate the analysis. INDEX TERMS MIMO, radio transmitters.
Shen REF proved that maximizing the SLNR is performed by concentrating all the available transmit power on a single data stream, regardless of the rank constraint.
Downlink Multi-User MIMO Precoding Design Via Signal-Over-Leakage Capacity
IEEE Access
IEEE Access
Computer Science