METHOD OF MEASURING ALTITUDE AND RADAR ALTIMETER WITH CONTINUOUS CHIRP SIGNAL USING SAID METHOD Russian patent published in 2015 - IPC G01S13/08 

FIELD: physics, navigation.

SUBSTANCE: invention relates to radar location of extended targets and can be used in on-board radar altimeters. Said result is achieved by emitting a probing signal vertically towards the earth's surface; receiving reflected signals at N repetition periods; filtering the received signal in a filter which is matched with modulation of the probing signal to obtain at each repetition period an envelope of the amplitude of the reflected signal; calculating dispersion of noise and the signal with noise for different hypotheses of the position of the jump of the dispersion of the reflected signal; determining the altitude of aircraft from the position of the jump of the dispersion of the reflected signal, wherein the method includes finding the position of the maximum of the weighted sum of logarithms of the dispersion of the noise and the signal with the noise; the weight of the first term is a negative number which corresponds to the position of the jump of the dispersion of the reflected signal in the hypothesis, and the weight of the second term is the negative difference between the maximum possible position of the jump of the dispersion of the amplitude of the reflected signal and the position of the jump of the dispersion n in the hypothesis.

EFFECT: providing the required measurement accuracy with low signal-to-noise ratio.

2 cl, 7 dwg, 1 ex