The disclosure relates to an active antenna array for a mobile communication system which comprises a plurality of receive paths, a sounding signal generator generating a sounding signal, and a coupler for coupling the sounding signal into at least one of a plurality of receive paths. A sounding signal extractor substantially removes the sounding signal from digitized ones of the receive signals to form a wanted signal. The disclosure also provides a method for the calibration of the receive path of the active antenna array.