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:
Mar. 03, 1981
Filed:
Jun. 04, 1979
Ronald W Mongeon, San Jose, CA (US);
Stellar Systems, San Jose, CA (US);
Abstract
An improvement in Instrusion Alarms of the type wherein a field wire acts as a transmitting antenna to produce an electric field and wherein a sense antenna is placed in the vicinity of the field wire to detect an intruder wherein at least one pair of field wires are employed at the extremities of a vertical configuration with sense wires between the field wires. The movement of a large object in the vicinity of such a system produces an equal perturbation on both of the sense wires so that no alarm is set off while an actual intrusion will cause a difference which is detected and utilized to provide an alarm system which is less susceptible to false alarms than the usual alarm systems.