METHOD FOR DETERMINING RANGE, RADIAL VELOCITY AND ANGULAR POSITION OF A TARGET IN A CW RADAR Russian patent published in 2023 - IPC G01S13/42 

FIELD: radars.

SUBSTANCE: invention can be used in radio engineering systems with continuous radiation, in which the receiving antennas are significantly removed from the transmitting ones, to determine the range, radial velocity and angular position of targets when they move significantly during the modulation period of a probing signal of long duration or over the interval of irradiating the target with a burst coherent signals. The technical result consists in increasing the accuracy of determining the spatial position of the target, eliminating the systematic error in measuring the range of the target and eliminating the ambiguity in determining its angular position. The claimed method consists in sounding the target with a broadband signal with linear frequency modulation (chirp), receiving, amplifying and demodulating the reflected signals from two spaced apart antennas. Then a set of reference signals with different chirp slopes is formed, each signal from the set is multiplied with the beat signals of both channels, and the complex spectra of the obtained multiplication results are calculated. The frequency components with the maximum amplitude are searched for in the calculated complex spectra, characterized by the corresponding numbers of the reference signals n_c1 and n_c2 and the value of their frequencies ƒ_Rd1 and ƒ_Rd2, determination by the values of n_c1 and n_c2 of the reference signal from the set of the corresponding radial velocities of the target and and Doppler frequencies and , calculation of the average value of the radial velocity of the target . The total ranges to the target R₁ + R₀ and R₂ + R₀ are calculated by values ƒ_Rd1 and ƒ_Rd2. The demodulated signal of one of the receiving channels is transferred to the reference frequency, the signal S_PD is generated, the amplitude of which varies in proportion to the sine of the current instantaneous phase difference of the signal at the reference frequency and the demodulated signal of the other receiving channel, the sign and magnitude U_BH of the deviation of the modulation frequency of the signal S_PD from the reference frequency, according to which and according to the values , , and the range and angular target position are calculated.

EFFECT: increasing the accuracy of determining the spatial position of the target, eliminating the systematic error in measuring the range of the target and eliminating the ambiguity in determining its angular position.

1 cl, 3 dwg