Method and apparatus for calibrating a filter of a receiver

摘要

According to a disclosed method, a calibration signal is provided at a first frequency corresponding to a low frequency edge of a desired passband to an input of a filter ( 240 ). A first value is measured at an output of the filter ( 240 ). The calibration signal is provided at a second frequency corresponding to a high frequency edge of the desired passband to the input of the filter ( 240 ). A second value is measured at the output of the filter ( 240 ). The first value is compared to the second value. A characteristic of the filter ( 240 ) is changed in response to the comparing. In one form, the filter is an IF filter ( 240 ) and a receiver ( 200 ) includes both the IF filter ( 240 ) and a calibration circuit ( 250 ) for forming the calibration signal and providing the calibration signal to the IF filter to change the characteristic in response to a calibration operation.