The invention relates to a navigation system receiver comprising at least two antennas, one of which is a "reference" antenna. A multiplexer multiplexes the signals from the antennas, and a first processor situated downstream from the multiplexer delivers at least one navigation parameter on the basis of the signals from the multiplexer. The receiver includes a second processor having an input receiving in continuous manner signals from the reference antenna to deliver at least one reference signal representative of a position parameter of the reference antenna. Processor means process the signals from the multiplexer while taking account of at least one said reference signal.