| 摘要 |
FIELD: physics, navigation.SUBSTANCE: invention refers to radar engineering. The disclosed method is carried out using a transponder, a transmitter and a receiver of a scanning device. The transmitter of the scanning device comprises a driving generator1, a modulating code generator 2, a phase-shift modulator 3, a power amplifier 4 and a transmitting antenna 5. The transponder is an interdigital transducer of surface acoustic waves (SAW) and comprises two comb-type electrode system 8, buses 9 and 10, reflectors 11 and a microstrip antenna 7. The microstrip antenna 7, electrodes 8, buses 9 and 10, reflectors 11 are deposited on the surface of a piezoelectric crystal 6. The receiver of the scanning device comprises receiving antennae 12-16, high frequency amplifiers 17-21, heterodynes 22 and 50, mixers 23 and 51, intermediate frequency amplifiers 24 and 52, spectrum analysers 25 and 27, a phase doubler 26, a comparator unit 28, switches 29 and 55, a phase halver 30, narrow band-pass filters 31, 37, 38, 39 and 40, a phase detector 32, multipliers 33-36, phase meters 41-44, subtractors 45 and 46, adders 47 and 48, a recording unit 49, a correlator 53 and a threshold unit 54.EFFECT: high selectivity and noise-immunity of the receiver of the scanning device by suppressing spurious signals (noise) received over image and combinational channels.6 dwg |
