SG72185G - Theft detection method and apparatus in which the decay of a resonant circuit is detected - Google Patents

Theft detection method and apparatus in which the decay of a resonant circuit is detected

Info

Publication number
SG72185G
SG72185G SG721/85A SG72185A SG72185G SG 72185 G SG72185 G SG 72185G SG 721/85 A SG721/85 A SG 721/85A SG 72185 A SG72185 A SG 72185A SG 72185 G SG72185 G SG 72185G
Authority
SG
Singapore
Prior art keywords
decay
detected
detection method
resonant circuit
theft detection
Prior art date
Application number
SG721/85A
Other languages
English (en)
Original Assignee
Knogo Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Knogo Corp filed Critical Knogo Corp
Publication of SG72185G publication Critical patent/SG72185G/en

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/22—Electrical actuation
    • G08B13/24—Electrical actuation by interference with electromagnetic field distribution
    • G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
    • G08B13/2405—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting characterised by the tag technology used
    • G08B13/2414—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting characterised by the tag technology used using inductive tags
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/22—Electrical actuation
    • G08B13/24—Electrical actuation by interference with electromagnetic field distribution
    • G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
    • G08B13/2465—Aspects related to the EAS system, e.g. system components other than tags
    • G08B13/2468—Antenna in system and the related signal processing
    • G08B13/2471—Antenna signal processing by receiver or emitter
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/22—Electrical actuation
    • G08B13/24—Electrical actuation by interference with electromagnetic field distribution
    • G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
    • G08B13/2465—Aspects related to the EAS system, e.g. system components other than tags
    • G08B13/2468—Antenna in system and the related signal processing
    • G08B13/2474—Antenna or antenna activator geometry, arrangement or layout
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/22—Electrical actuation
    • G08B13/24—Electrical actuation by interference with electromagnetic field distribution
    • G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
    • G08B13/2465—Aspects related to the EAS system, e.g. system components other than tags
    • G08B13/2468—Antenna in system and the related signal processing
    • G08B13/2477—Antenna or antenna activator circuit
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/22—Electrical actuation
    • G08B13/24—Electrical actuation by interference with electromagnetic field distribution
    • G08B13/2402—Electronic Article Surveillance [EAS], i.e. systems using tags for detecting removal of a tagged item from a secure area, e.g. tags for detecting shoplifting
    • G08B13/2465—Aspects related to the EAS system, e.g. system components other than tags
    • G08B13/2488—Timing issues, e.g. synchronising measures to avoid signal collision, with multiple emitters or a single emitter and receiver

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Automation & Control Theory (AREA)
  • Computer Security & Cryptography (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Signal Processing (AREA)
  • Burglar Alarm Systems (AREA)
SG721/85A 1981-10-23 1985-10-05 Theft detection method and apparatus in which the decay of a resonant circuit is detected SG72185G (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US06/314,440 US4476459A (en) 1981-10-23 1981-10-23 Theft detection method and apparatus in which the decay of a resonant circuit is detected

Publications (1)

Publication Number Publication Date
SG72185G true SG72185G (en) 1986-05-02

Family

ID=23219954

Family Applications (1)

Application Number Title Priority Date Filing Date
SG721/85A SG72185G (en) 1981-10-23 1985-10-05 Theft detection method and apparatus in which the decay of a resonant circuit is detected

Country Status (15)

Country Link
US (1) US4476459A (da)
JP (1) JPS5882392A (da)
AU (1) AU533743B2 (da)
BE (1) BE894760A (da)
BR (1) BR8206167A (da)
CA (1) CA1196409A (da)
DE (1) DE3235434C2 (da)
DK (1) DK157636C (da)
FR (1) FR2515362A1 (da)
GB (1) GB2112252B (da)
IT (1) IT1148418B (da)
NL (1) NL185735C (da)
SE (1) SE457577B (da)
SG (1) SG72185G (da)
ZA (1) ZA826194B (da)

Families Citing this family (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4623877A (en) 1983-06-30 1986-11-18 Knogo Corporation Method and apparatus for detection of targets in an interrogation zone
US4531117A (en) * 1983-07-05 1985-07-23 Minnesota Mining And Manufacturing Company Variable frequency RF electronic surveillance system
US4609911A (en) * 1983-07-05 1986-09-02 Minnesota Mining And Manufacturing Company Variable frequency RF electronic surveillance system
CA1234892A (en) * 1984-02-16 1988-04-05 Pierre Taillefer Security tag detection system
US4642613A (en) * 1984-03-16 1987-02-10 Knogo Corporation Electronic theft detection apparatus with responder elements on protected articles
US4683461A (en) * 1985-09-17 1987-07-28 Allied Corporation Inductive magnetic field generator
US4644286A (en) * 1985-09-17 1987-02-17 Allied Corporation Article surveillance system receiver using synchronous demodulation and signal integration
US4658241A (en) * 1985-09-17 1987-04-14 Allied Corporation Surveillance system including transmitter and receiver synchronized by power line zero crossings
US4667185A (en) * 1985-12-06 1987-05-19 Minnesota Mining And Manufacturing Company Wireless synchronization system for electronic article surveillance system
NL8803170A (nl) * 1988-12-27 1990-07-16 Nedap Nv Identificatiesysteem.
CH681051A5 (da) * 1989-03-22 1992-12-31 Actron Entwicklungs Ag
US5083113A (en) * 1990-01-31 1992-01-21 Texas Instruments Incorporated Inductive coupled object identification system and method
US5382780A (en) * 1993-10-01 1995-01-17 Duncan Industries Parking Control Systems Corp. Portable time metering device
SE508322C2 (sv) * 1994-02-07 1998-09-28 Leif Aasbrink Larmelement
JPH07263935A (ja) * 1994-03-24 1995-10-13 Hochiki Corp アンテナ装置
US5469142A (en) * 1994-08-10 1995-11-21 Sensormatic Electronics Corporation Electronic article surveillance system having enhanced tag deactivation capacity
DE4436977A1 (de) * 1994-10-15 1996-04-18 Esselte Meto Int Gmbh Anlage zur elektronischen Artikelüberwachung
DE19514601A1 (de) * 1995-04-20 1996-10-24 Esselte Meto Int Gmbh Anlage zur elektronischen Artikelüberwachung, insbesondere zur Detektion von Schwingkreisen mit stark unterschiedlichen Resonanzfrequenzen
US5798693A (en) * 1995-06-07 1998-08-25 Engellenner; Thomas J. Electronic locating systems
DE19653931A1 (de) * 1996-12-21 1998-06-25 Meto International Gmbh Vorrichtung und Verfahren zur elektronischen Sicherung von Artikeln gegen Diebstahl
US5745071A (en) * 1997-03-10 1998-04-28 Mcdonnell Douglas Corporation Method and apparatus for precisely locating a resonant object
US5990791A (en) * 1997-10-22 1999-11-23 William B. Spargur Anti-theft detection system
GB2352931A (en) * 1999-07-29 2001-02-07 Marconi Electronic Syst Ltd Piezoelectric tag
US6249229B1 (en) 1999-08-16 2001-06-19 Checkpoint Systems, Inc., A Corp. Of Pennsylvania Electronic article security system employing variable time shifts
US7088236B2 (en) * 2002-06-26 2006-08-08 It University Of Copenhagen Method of and a system for surveillance of an environment utilising electromagnetic waves
WO2004003591A1 (en) * 2002-06-26 2004-01-08 It-Højskolen A method of and a system for surveillance of an environment utilising electromagnetic waves
US9312598B1 (en) * 2007-09-07 2016-04-12 Callas Enterprises, LLC Combined floor mat and antennas for an electronic article surveillance system
US11242239B2 (en) 2017-02-14 2022-02-08 Gilbarco Inc. Fuel dispenser with fraud resistant flow control valve
US11201641B2 (en) * 2019-05-08 2021-12-14 Raytheon Bbn Technologies Corp. Apparatus and method for detection of cyber tampering, physical tampering, and changes in performance of electronic devices
US12111419B1 (en) 2019-06-25 2024-10-08 Board Of Trustees Of The University Of Alabama, For And On Behalf Of The University Of Alabama In Huntsville Systems and methods for detecting objects

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US2812427A (en) * 1951-06-27 1957-11-05 Alexander F Passive radio communication system
US2899546A (en) * 1954-05-25 1959-08-11 hollmann
US2958781A (en) * 1956-03-22 1960-11-01 Marchal Maurice Radio-physiological method and means
US3117277A (en) * 1957-09-04 1964-01-07 Karl Rath Passive radio repeater transmission system
JPS36022343B1 (da) * 1959-12-24 1961-11-18 Univ Tokyo
US3273146A (en) * 1964-08-07 1966-09-13 Gen Electric Object identifying apparatus
US3373425A (en) * 1967-04-14 1968-03-12 Allen L Well Tunnel diode circuit utilized to control the reply of a passive transponder
GB1298381A (en) * 1969-02-26 1972-11-29 Unisearch Ltd Passive labels for use in electronic surveillance systems
US3740742A (en) * 1971-05-11 1973-06-19 T Thompson Method and apparatus for actuating an electric circuit
US3810172A (en) * 1972-07-18 1974-05-07 L Burpee Detection system
GB1433140A (en) * 1972-10-17 1976-04-22 Nat Res Dev Indentity transponders
US3919704A (en) * 1972-12-04 1975-11-11 Check Mate Systems Inc System and method for detecting unauthorized removal of goods from protected premises, and magnet detecting apparatus suitable for use therein
US3836842A (en) * 1973-01-22 1974-09-17 Bell Canada Northern Electric Encapsulated electrically resonant circuit and interrogating apparatus and method for finding same in various locations
US3828337A (en) * 1973-08-20 1974-08-06 G Lichtblau Noise rejection circuitry
US3938044A (en) * 1973-11-14 1976-02-10 Lichtblau G J Antenna apparatus for an electronic security system
US3911534A (en) * 1974-10-30 1975-10-14 I D Engineering Inc Anti-theft fastening device
US4135184A (en) * 1977-08-31 1979-01-16 Knogo Corporation Electronic theft detection system for monitoring wide passageways
GB2012524A (en) * 1977-12-09 1979-07-25 Lintech Instr Ltd Transponders
US4215342A (en) * 1978-03-31 1980-07-29 Intex Inc. Merchandise tagging technique
US4321586A (en) * 1980-08-21 1982-03-23 Knogo Corporation Article theft detection

Also Published As

Publication number Publication date
SE457577B (sv) 1989-01-09
ZA826194B (en) 1984-04-25
BR8206167A (pt) 1983-09-20
JPH0158555B2 (da) 1989-12-12
SE8205993D0 (sv) 1982-10-21
IT1148418B (it) 1986-12-03
DE3235434C2 (de) 1985-07-25
NL185735C (nl) 1990-07-02
GB2112252B (en) 1985-06-12
AU533743B2 (en) 1983-12-08
DE3235434A1 (de) 1983-05-11
JPS5882392A (ja) 1983-05-17
GB2112252A (en) 1983-07-13
FR2515362B1 (da) 1985-03-01
SE8205993L (sv) 1983-04-24
DK419282A (da) 1983-04-24
FR2515362A1 (fr) 1983-04-29
IT8249322A0 (it) 1982-10-21
AU8784282A (en) 1983-06-16
CA1196409A (en) 1985-11-05
NL8203419A (nl) 1983-05-16
US4476459A (en) 1984-10-09
DK157636B (da) 1990-01-29
DK157636C (da) 1990-07-09
BE894760A (fr) 1983-02-14

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