The method in accordance with the invention, implemented with the aid of at least one pair of antennas, consists in performing: a normalized spectral analysis before intercorrelation of the demodulated signals (I, Q), by the code and the carrier, a phase coherence resetting of the signals before recombination, a phase offset measurement carried out by a true intercorrelation of the homologous satellite pathways by interferometry of the two signals arising from one and the same satellite and received respectively by a pair of antennas, then in performing a reduction of the initial ambiguity removal search domain for the determination of attitude of a vehicle by interferometric GPS measurement and implementing a statistical test for the selection of the ambiguity.