Quadrature receiver mismatch calibration

This article introduces nonlinear regression techniques to estimate gain and phase mismatches between the in-phase (I) and quadrature (Q) branches of a quadrature receiver. Under modest assumptions, the system intrinsically follows a nonlinear regression model. The algorithm is effective, easily implemented, customizable, and requires few assumptions. Large-sample, jackknife, and bootstrap techniques provide on-line error assessment and parameter inference.