NONLINEAR RADAR Russian patent published in 2024 - IPC G01S13/30 G01S13/88 G01V3/12 

FIELD: radio engineering.

SUBSTANCE: invention relates to radar systems, and is intended for detection of hidden nonlinear electronic devices (NED). Nonlinear radar, comprising a transmitter, a receiving-transmitting antenna, a receiving device and a display device, additionally a pulse generator, a synchronization device, a directional duplexer, a processing device, a sampling and storage device and a decision-making device are introduced. Pulse generator provides formation of modulating signal in form of periodic sequence of first and second pulses of rectangular shape, wherein the first pulse has amplitude a₁, duration is τ₁, the second pulse has amplitude a₂, duration is τ₂ and is delayed relative to the trailing edge of the first pulse by the value Δt. Modulating signal is transmitted to the input of the synchronization device and to the input of the transmitter, which provides formation of probing radio signal in form of periodic sequence of first and second radio pulses at fundamental frequency ƒ₁, in which the amplitude of the first radio pulse A₁ differs from the amplitude of the second radio pulse A₂ by N times, and the duration of the first radio pulse τ₁ differs from the duration of the second radio pulse τ₂ by N² times in the inverse ratio. Transmitter through direct channel of directional duplexer transmits probing radio signal to input of receiving-transmitting antenna, providing the direction of the probing radio signal to the field of view and the conversion of radio waves reflected from the field of view into the received radio signal at the fundamental frequency ƒ₁, which is fed through the reverse path of the directional duplexer to the input of the receiving device. Signals reflected from NED are processed at the fundamental frequency of the probing signal due to quantitative differences in the effect of nonlinearity of current-voltage characteristics of nonlinear elements of electronic devices on signal amplitudes at the frequency of the fundamental harmonic and on the levels of higher harmonics.

EFFECT: simplified design and increased range of NED detection.

1 cl, 2 dwg