Min-max SNR Optimization of Virtual Channel for Overloaded MIMO Systems

Abstract

In this paper, a new virtual channel optimization method in superposition virtual channel (SVC) overloaded multiple-input multiple-output (MIMO) system is proposed. Through the min-max optimization method on virtual channel, the optimal virtual channel vector can be found. The virtual channel vector is optimized by minimizing the maximum achievable rate at the receiver. Conventional closed-solution optimization scheme reduces the overall system performance due to the low signal to noise ratio (SNR) of one receive antenna. With this approach, the output SNR of each receive antenna is fairly allocated, which is used to obtain achievable rate on individual receive antenna. Compared with the closed-solution optimization scheme, it has fairer achievable rate on each receive antenna. The simulation results show the effectiveness of the new optimization method.