Method and apparatus for detection of targets in an interrogation zone
作者： Pierre Felix Buckens
DOI:
关键词: Electrical engineering 、 Harmonics 、 Transmitter antenna 、 Interrogation 、 Comparator 、 Magnetic field 、 Asymmetry 、 Saturation (magnetic) 、 Optics 、 Physics
摘要: Targets (30) of readily saturable mangetic material and mounted on protected articles (14) are detected when taken through an interrogation zone (24) in which alternating magnetic field is generated by transmitter antenna coils (42, 44). The target driven alternately into out saturation it disturbs the a manner so as to produce fields at frequencies harmonics frequency field. composite these has characteristic asymmetry due effect earth's responses receiver (50, 52) first detection signals processed compressor (118) signal averager (124) compared comparator (146) with alarm signals.
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