Asymmetrical antennas for use in electronic security systems
Patent 4260990 Issued on April 7, 1981. Estimated Expiration Date: 
November 8, 1999. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
November 8, 1999. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.InventorApplicationNo. 06/092325 filed on 11/08/1979US Classes:343/742, Plural340/572.5, Having tuned resonant circuit340/572.7Specified antenna structureExaminersPrimary: Lieberman, EliAttorney, Agent or FirmInternational ClassesG08B 13/24 (20060101)H01Q 7/00 (20060101) AbstractAn antenna system for use in an electronic security system and having a transmitting antenna with at least one loop lying in a plane, and a receiving antenna having at least two twisted loops lying in a common plane with each loop being twisted 180° and in phase opposition with each adjacent loop. The transmitting and receiving antennas are disposed in spaced substantially parallel relationship across an aisle or passage through which a resonant tag circuit must pass for detection. | |
