METHOD OF DETECTING SINGLE-LOOP PARAMETRIC SCATTERERS Russian patent published in 2011 - IPC G01S13/74 

FIELD: physics.

SUBSTANCE: when detecting single-loop parametric scatterers with natural frequency of parametric excitation 0.5f, a synchronising radio-frequency pulse is emitted at frequency 1.5f. Synchronisation takes place from the differential combinatorial nonlinear product formed by pumping radio-frequency pulses formed on the nonlinear capacitance of the parametric scatterer and a synchronising signal 1.5f - f = 0.5f, or an additional radio-frequency pulse at frequency O is emitted together with the synchronising signal at frequency f2. One of the combinatorial nonlinear products satisfies the condition nf ± mf = 0.5f, where n and m are integers. The synchronising and the additional radio-frequency pulse are emitted simultaneously or a little latter than the pumping radio-frequency pulse. Under the effect of these radio-frequency pulses, combinatorial nonlinear noise at frequency of the received signal 0.5f may appear on the noise nonlinear scatterers. In order to compensate for this noise, a compensating radio-frequency pulse is emitted after the synchronising radio-frequency pulse at the same frequency and with duration equal to the overlap time of the synchronising radio-frequency pulse and the pumping radio-frequency pulse. When using an additional radio-frequency pulse, said pulse is also simultaneously emitted with the compensating radio-frequency pulse.

EFFECT: increased noise immunity.

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