CPC G01S 13/60 (2013.01) [B60R 11/00 (2013.01); G01S 15/60 (2013.01); G01S 13/18 (2013.01); G01S 13/524 (2013.01); G01S 13/589 (2013.01); G01S 13/64 (2013.01); G01S 13/882 (2013.01); G01S 13/931 (2013.01)] | 10 Claims |
1. A method for measuring the velocity of a carrier vehicle with respect to the ground, the carrier vehicle moving parallel to the ground and being equipped with a radar or sonar having an emission and reception cone about a line of sight, the method comprising the following steps:
(a) orienting the line of sight of the radar or sonar toward the ground, such that a footprint on the ground of said emission and reception cone is passed through by the projection onto the ground of the velocity vector of the carrier vehicle;
(b) using the radar or sonar to emit a plurality of signals that are directed toward the ground, and to acquire respective echo signals at a plurality of echo delay time values;
(c) processing the acquired echo signals so as to obtain, for one or more of the plurality of echo delay time values, a corresponding Doppler spectrum;
(d) for said one or more echo delay time value, identifying an uppermost, in absolute value, frequency value of the corresponding Doppler spectrum; and
(e) computing the velocity of the carrier vehicle with respect to the ground as a function of: its height with respect to the ground, said one or more uppermost frequencies and the corresponding echo delay time values.
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