An LMMSE-Based Receiver for Uplink Massive MIMO Systems With Randomized IQ Imbalance

In-phase/quadrature-phase imbalance (IQI) is one of the hardware impairments in uplink massive multiple-input multiple-output systems. In this context, by modeling the IQI parameters as random variables, this letter first analyzes the statistic property of the effective channel in which both the IQI parameters and channel state information are included. By doing so, an LMMSE-based receiver is then investigated for channel estimation and data detection. Furthermore, we provide tightness analysis on asymptotic achievable sum rate for the proposed scheme using results from random matrix theory. Finally, simulation results show that our proposed scheme has small performance loss but with the advantage that estimating IQI parameters can be avoided.