The present invention provides for a method and system for compensating phase offset caused by a matching network and antenna of a communications device. The method comprises: generating a mapping that correlates phase offset with a characteristic parameter; measuring the characteristic parameter for the communications device; using the measured characteristic parameter and the mapping to determine a phase offset for the communications device; and using the determined phase offset to compensate for the phase offset caused by the matching network and antenna of the communications device. The present invention also provides for a method and system for measuring a phase offset caused by a matching network and antenna of a communications device.