Balance error estimator in a quadrature modulator and modulation stage using the estimator

摘要

The estimator (24) detects the instantaneous power of a modulated signal produced by two mixers which receive the in-phase and quadrature signal components respectively of an input signal. The signal components are then summed to produce the modulated signal. The detected instantaneous power is multiplied by the modulated signal components to provide signal products which are then rectified. The rectified signals are integrated to provide signals which indicate an imbalance in the modulator.