The present invention provides a method for automatic calibration of a
signal path in receivers (e.g., radio frequency receivers) using a noise
(and not a specific test signal) as a source and a fast Fourier transform
(FFT) of the noise for correcting various parameters related to an
inphase/quadrature (I/Q) imbalance in a frequency domain. The present
invention (method and apparatus) can provide detecting and correcting an
I/Q phase error, an I/Q amplitude error, an absolute corner frequency of
the analog baseband filter, and a relative corner frequency of the analog
baseband filters just by using the noise as a stimuli. This calibration
can be used for a factory calibration or it can be used as an on-site
calibration for base stations. Mobile devices can calibrate themselves
independently of their location. This reduces the requirements for the
test equipment in the manufacturing and maintenance stages.