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:
Aug. 24, 1999
Filed:
Aug. 13, 1997
Applicant:
Inventors:
John P Palmer, Pomona, CA (US);
Mohammad A Asgari, Canyon Country, CA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G08B / ;
U.S. Cl.
CPC ...
3405725 ; 34082554 ; 340571 ; 343745 ; 455 78 ; 455 41 ; 455 63 ; 455 83 ;
Abstract
A transponder adapted to be used in a checkout or inventory control system is disclosed which transmits by modulating and re-radiating a transponder signal frequency derived from a carrier frequency received on a transmitting antenna. The transponder includes a dual mode antenna and circuitry which selectively operates the antenna to suppress undesired emission of the transponder signal frequency when the transponder is not transmitting. A terminating circuit is further disclosed which suppresses undesired emission of the transponder signal frequency by a demodulator portion of the transponder.