The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 15, 1981
Filed:
Nov. 09, 1979
Robert J McFadyen, Syracuse, NY (US);
John F Zeigler, III, Newtown, CT (US);
General Electric Company, Syracuse, NY (US);
Abstract
An ultrasonic intrusion alarm system of the pulse-echo type transmits pulsed signals which are reflected by a reference surface. The resulting reference received pulsed signals appear as corresponding signals at the output of the system's receiver, which is gated on in coincidence with the arrival of said reference signals and is gated off at essentially all other times for minimum power consumption, the output signal state of said receiver being employed to cause the generation of an alarm signal upon the occurrence of an intrusion. The receiver includes an AGC amplifier network which exhibits a threshold voltage level that is a function of the signal strength of said reference signals which level is compared with the amplified received signals whereby said alarm is generated when said threshold level fails to be exceeded, such as due to an interruption of said signals.