Joint Automatic Gain Control and MMSE Receiver Design for Quantized Multiuser MIMO Systems

Abstract

This paper presents the development of a joint optimization of an automatic gain control (AGC) algorithm and a linear minimum mean square error (MMSE) receiver for multiuser multiple input multiple output (MU-MIMO) systems with coarsely quantized signals. The optimization of the AGC is based on the minimization of the mean square error (MSE) and the proposed receive filter takes into account the presence of the AGC and the effects due to quantization. Moreover, we provide a lower bound on the capacity of the MU-MIMO system by deriving an expression for the achievable rate. The performance of the proposed Low-Resolution Aware MMSE (LRA-MMSE) receiver and AGC algorithm is evaluated by simulations, and compared with the conventional MMSE receive filter and Zero-Forcing (ZF) receiver using quantization resolution of 2, 3, 4 and 5 bits.