Patent ID: 8477889

Claim:
A method for compensating a modulation imbalance effect in a communication device, the method comprising: receiving first digital samples representing a baseband signal configured to have a first frequency; estimating at least three sets of modulation imbalance parameters from the first digital samples, each set of modulation imbalance parameters having a gain modulation imbalance parameter and a phase modulation imbalance parameter; generating a first offset signal to cause the baseband signal to be configured to have a second frequency; receiving second digital samples representing the baseband signal configured to have the second frequency; estimating at least three sets of modulation imbalance parameters from the second digital samples, each set of modulation imbalance parameters having a gain modulation imbalance parameter and a phase modulation imbalance parameter; generating a second offset signal to cause the baseband signal to be configured to have a third frequency; receiving third digital samples representing the baseband signal configured to have the third frequency; estimating at least three sets of modulation imbalance parameters from the third digital samples, each set of modulation imbalance parameters having a gain modulation imbalance parameter and a phase modulation imbalance parameter; filtering the gain modulation imbalance parameters and the phase imbalance parameters at each frequency to obtain a filtered set of modulation imbalance parameters for that frequency, each filtered set of modulation imbalance parameters having a gain modulation imbalance parameter and a phase modulation imbalance parameter; and reconstructing input signals with the filtered set of modulation imbalance parameters for each frequency.