Optimizing the noisy MIMO Interference Channel at High SNR

Centralized algorithms for weighted sum rate (WSR) maximization for the K-user frequency-flat MIMO Interference Channel (MIMO IFC) with full channel state information (CSI) are considered. Maximization of WSR is desirable since it allows the system to cover all the rate tuples on the rate region boundary for a given MIMO IFC. First, we propose an iterative algorithm to design optimal linear transmitters and receivers. The transmitters and receivers are optimized to maximize the WSR of the MIMO IFC. Subsequently, we study the problem of WSR maximization in the High SNR regime. Starting from the High SNR approximation of the WSR we observe that the optimization problem in High SNR becomes, in a first instance, an exploration of the (discrete) pre-log region. Once the optimal pre-log distribution if found, for a given set of weights, the WSR optimization becomes the maximization of the High SNR Rate offset. To avoid the many local optima indicated by this analysis, the use of Deterministic Annealing in 1/SNR is suggested.