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AssigneeThomson-CSF
InventorYves Canal
Estimating the term…
The wave is modulated in frequency (or in phase) and a measurement is made of the frequency of the beat between the transmitted wave and the received wave which gives the propagation delay and hence the distance. The method provides for the superimposing, on this modulation, of a periodic over-modulation with a period that is equal to or is a multiple of the propagation delay corresponding to a pre-selected expected distance. The device comprises, at transmission, in the case of a linear modulation of frequency, a saw-tooth generator (31) and a generator of over-modulations (32), for example sinusoidal, controlled by the expected distance given by a distance selector (30). The modulation signal of the transmitter is obtained by summation (33) of the signals of the two generators (31, 32).
A method to determine the passing of a reflector point by a pre-selected distance from a transmitter by indirect measurement of the delay of propagation, between said transmitter and a receiver means, of a continuous wave modulated according to a modulation, chosen between phase modulation and frequency modulation, and reflected at said point, said method comprising the steps of:
A device having a transmitter and receiver means to determine the passing of a reflector point by a pre-selected distance of said transmitter by indirect measurement of the delay of propagation, between said transmitter and said receiver means, of a continuous wave modulated according to a modulation, chosen between phase modulation and frequency modulation, and reflected at said point, said device further comprising:
Dependencies are inferred from the claim text.