03967161 is referenced by 189 patents and cites 1 patents.

An electronic security system adapted for use in a controlled area such as a retail store and employing a multi-frequency resonant tag circuit having distinct frequencies for detection and discrimination. An electromagnetic field is provided within the controlled area at a frequency which is swept through a range including the detection frequency of the resonant tag circuit. In the presence of a tag circuit within the controlled area, pulses are detected by a receiver which includes noise rejection circuitry for discriminating true signals from noise. The noise rejection circuitry is sensitive to expected signals and operative to discriminate true signals from noise on the basis of several different criteria, resulting in substantially reduced false alarm actuation.

A multi-frequency resonant tag circuit for use with an electronic security system having improved noise discrimination
Application Number
Publication Number
Application Date
July 19, 1974
Publication Date
June 29, 1976
George Jay Lichtblau
425 E. 63rd St. Suite E - 12-D, New York, 10021
Weingarten Maxham & Schurgin
G08B 21/00
H02B 9/00
H02B 1/04
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