Two calibration methods of wideband quadrature receiver mismatch errors

Abstract

The theory of digital calibration for the gain and phase imbalances between the in-phase and quadrature branches of a wideband receiver is discussed. Two novel and practical methods for the estimation of the relative amplitude and phase error function are presented, including the least squares and a modification based on the principle of Gram-Schmidt orthogonalization. Computer simulations show their effectiveness.