Parametric Modeling in Mitigating the I/Q Mismatch: Estimation, Equalization, and Performance Analysis

In this work, we, using a mapping, transform the mismatch compensation problem into an estimation and equalization problem. By doing so, the in-phase and quadrature (I/Q) system mismatch parameters, i.e., the amplitude gains of I/Q channels and the phase imbalance, can be first estimated reliably and then mitigated by equalization. We also derive the Cramer-Rao lower bounds (CRLBs) of the parameters and study the performances of different phase imbalance estimates. Simulation results show that the mean square errors of the estimated parameters follow the trends of their corresponding CRLBs. Hence the I/Q mismatch can be mitigated by equalization successfully.