An autonomous positioning system is proposed for navigation of terrestrial transport based on microwave radar displacement sensors. An algorithm for direct and continuous measurement of the displacement vector using a quadrature mixer and counter for the number of half periods of the Doppler signal is discussed. The advantages of this method over measuring the velocity vector from the spectrum of the Doppler signal are described. Tests of the direct displacement sensor are carried out using a 24.05 GHz radar Doppler module with a quadrature output. The cumulative error in determining the coordinates on an area is found to decrease signifi cantly compared to an inertial positioning system. The advantages of this method in hybrid navigation systems when it is used together with a global positioning system are pointed out. Keywords: autonomous navigation, Doppler effect, microwave sensor, short-range radar, antenna, mutual correlation, quadrature mixer.