| 摘要 |
search and rescue service. SUBSTANCE: procedure is intended for active probing of obstructions formed as result of emergencies and natural calamities for objective detection of presence of man with signs of life such as breathing, heart beat, stirring. Radio frequency signal with duration Tu is emitted in accordance with procedure. Reflected signal is received in fixed time interval Tn equal in duration to fixed duration Tu of emitted signal with delay tau3 between finish of emission of signal and start of reception of reflected signal. If modulated component with frequency of pulse and/or breathing of man is detected its level is measured. Duration of reception of reflected signal is changed to decreased level of modulated component relative to its level of initial reflected radio frequency signal and to moment of finish of its arrival. Distance is found by duration of reception of reflected signal with modulated component. Microwave locator for realization of procedure incorporates modulator and transmitter composed of generator, power divider and transmitting antenna. Receiver includes receiving antenna, SHF receiver, preamplifier/demodulator, signal processing unit. Modulator with change of carrier frequency can change duration of controlling pulses and their recording. Locator is supplemented with first pulse modulator of transmitter and second pulse SHF of receiver. Modulator has controlling output coupled to controlling input of second pulse modulator to receive reflected signal by receiver with delay with regard to termination of emission of signal by transmitter and change of time of switch-on of SHF receiver. Signal processing unit can measure level of modulated component. EFFECT: enhanced quality of detection and noise immunity. 16 cl, 16 dwg
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