The product on the basis of the original further use of a more advanced digital logic circuit, the received signal processing, the application of software to the digital logic circuit processing out of the signal, identification, extraction, comparison, alarm. And the use of liquid crystal display panel mode, human-machine communication humanized, intelligent. Higher sensitivity, stronger anti-interference ability, more perfect stability. The overall appearance is strong, simple and elegant. Suitable for places with high sensitivity requirements; Prisons, detention houses, public security laws, airports, museums, embassies, troops, exhibitions, stadiums, venues, examination halls, important government departments and other places.