Patent ID: 7376170
Filing Date: 2008-05-20
Classification: H03D,H04L

Abstract:
1. A digital imbalance correction device, comprising: an input unit configured to receive first input signals containing a plurality of channels from an I/Q converter stage at respective input terminals, each input terminal being associated to a respective signal branch; a time-to-frequency-domain-transformer configured to perform a transformation of said first input signals from time-domain into frequency-domain, the transformation result being represented as a power spectrum of said respective first input signals; a subtracting unit configured to receive at its inputs second input signals which are represented by the power spectra of said respective transformed first input signals and to output a gain difference as a function of frequency at its output; a cross-correlator configured to receive at its inputs third input signals based on said first input signals, and to output a cross-correlation of said third input signals, said cross-correlation output being proportional to a phase error between said respective correlation input signals; a gain corrector arranged in one of said respective signal branches and configured to receive at its input a fourth input signal based on said associated first input signal, wherein a gain of said fourth input signal is corrected based on said power difference spectrum such that said gain of said fourth input signal equals the gain of the other one of said first input signals; and a phase corrector arranged in one of said respective signal branch and configured to receive at its input a fifth input signal based on said associated first input signal, wherein a phase of said fifth input signal is corrected based on said cross-correlation output, such that said phase of said fifth input signal is in quadrature relation to the other one of said first input signals.