Patent Document ID: 20110187586
Application ID: 12969929
Patent Status: 0

Claim One:
1. A continuous-emission radar detection method, a propagation delay for a useful target situated at the maximum radar range being greater than a duration of an elementary ramp, said method comprising: generating a frequency-modulated continuous signal, an emission sequence being formed of successive and contiguous ramps, of excursion ΔF and the duration Tr, which are centred on a carrier frequency F 1 ; simultaneously and continuously receiving from at least one target an echo corresponding to the signal emitted, delayed by a propagation time for the outward-return journey to the said target kTr+θ, k being an integer and θ a duration less than Tr; demodulating the signal received by the signal emitted, the resulting signal being composed for each emission ramp of a first section of sinusoid at the frequency δFdim=(1−(θ/Tr))·ΔF and of a second sinusoid at the frequency δFd=(θ/Tr)·ΔF; sampling at each ramp, in a continuous manner and in synchronism with the emission signal, the resulting signal, the start and the end of each sampling sequence being chosen respectively at the start and at the end of each emission ramp; performing a first digital Fourier transform FFT, on the distance axis on the said resulting signal, at each sequence corresponding to the duration of an emission ramp; performing the vector sum of the two spectral lines appearing at the frequencies δFd and δFdim on output from the FFT, after resetting them into phase with respect to one another; and performing a detection by comparing the modulus of the vector sum with a predetermined threshold.