Gradient-based search technique using for M-QAM signals' DC-offset estimation and compensation

Abstract

The possibility of using a gradient search technique to compensate the DC offset at the output of the quadrature converter is investigated in this research. The preliminary compensation of I/Q imbalance is assumed. The results of the work are a simulation model of a demodulator created in MATLAB SIMULINK in order to analyze the use of this method when receiving signals with M-QAM modulation, and frequency spectrum before and after calibration for QAM-4, -16, -32.