2results about "Line balance variation compensation" patented technology

The application discloses an IQ imbalance blind calibration method and an IQ modulation demodulator. The method comprises the following steps: determining a regularity judgment condition based on the characteristics of the second-order statistics of a complex signal under ideal conditions; building an IQ imbalance mathematical model to determine a compensation mode; obtaining a compensation coefficient formula based on the compensation mode, the regularity judgment condition and a step diagonal matrix; substituting the complex signal into the compensation coefficient formula to obtain a high-order LMS double-channel algorithm model; and introducing a nonlinear step error model into the high-order LMS double-channel algorithm model. The application provides a frequency-dependent square difference operation variable step IQ imbalance double-channel high-order blind compensation filtering algorithm, and any prior information is not needed. The signal mismatch adjustment algorithm parameters are adjusted according to the phase mismatch and amplitude imbalance of the input signal, so that the signal can maintain an ideal orthogonal relationship.

This application provides an IQ imbalance calibration method, apparatus, signal transmitter, and zero-IF transceiver. The method includes: acquiring a reference baseband signal and a radio frequency (RF) signal output by the IQ modulation channel based on the reference baseband signal, and converting the RF signal into a modulation baseband signal; reconstructing the modulation baseband signal to generate a baseband feedback signal characterizing the distortion of the IQ modulation channel; obtaining pre-distortion parameters for compensating for IQ imbalance based on the reference baseband signal and the baseband feedback signal; performing pre-distortion processing on the reference baseband signal using the pre-distortion parameters to generate a baseband pre-distortion signal; and performing imbalance calibration on the IQ modulation channel based on the baseband pre-distortion signal. Because the IQ modulation channel is calibrated, the image rejection ratio and error vector amplitude performance of the output signal can be improved, thus increasing the calibration accuracy of the IQ modulation channel.