NO912997L - TABLE OF FREQUENCY PARTS. - Google Patents

TABLE OF FREQUENCY PARTS.

Info

Publication number
NO912997L
NO912997L NO91912997A NO912997A NO912997L NO 912997 L NO912997 L NO 912997L NO 91912997 A NO91912997 A NO 91912997A NO 912997 A NO912997 A NO 912997A NO 912997 L NO912997 L NO 912997L
Authority
NO
Norway
Prior art keywords
circuit
frequency
resonant
electromagnetic radiation
response
Prior art date
Application number
NO91912997A
Other languages
Norwegian (no)
Other versions
NO912997D0 (en
Inventor
Fred Wade Herman
Ming Ren Lian
Original Assignee
Security Tag Systems Inc
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
Priority claimed from US07/562,475 external-priority patent/US5065137A/en
Priority claimed from US07/562,471 external-priority patent/US5065138A/en
Application filed by Security Tag Systems Inc filed Critical Security Tag Systems Inc
Publication of NO912997D0 publication Critical patent/NO912997D0/en
Publication of NO912997L publication Critical patent/NO912997L/en

Links

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING SYSTEMS, e.g. PERSONAL 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
    • G08B13/242—Tag deactivation
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING SYSTEMS, e.g. PERSONAL 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
    • G08B13/2422—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 acoustic or microwave tags
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING SYSTEMS, e.g. PERSONAL 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
    • G08B13/2422—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 acoustic or microwave tags
    • G08B13/2425—Tag deactivation
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING SYSTEMS, e.g. PERSONAL 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
    • G08B13/2428—Tag details
    • G08B13/2431—Tag circuit details
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING SYSTEMS, e.g. PERSONAL 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
    • G08B13/2428—Tag details
    • G08B13/2437—Tag layered structure, processes for making layered tags
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING SYSTEMS, e.g. PERSONAL 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
    • G08B13/2428—Tag details
    • G08B13/2437—Tag layered structure, processes for making layered tags
    • G08B13/2442—Tag materials and material properties thereof, e.g. magnetic material details

Landscapes

  • Physics & Mathematics (AREA)
  • Automation & Control Theory (AREA)
  • Computer Security & Cryptography (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Burglar Alarm Systems (AREA)
  • Radar Systems Or Details Thereof (AREA)
  • Geophysics And Detection Of Objects (AREA)
  • Indexing, Searching, Synchronizing, And The Amount Of Synchronization Travel Of Record Carriers (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Inductance-Capacitance Distribution Constants And Capacitance-Resistance Oscillators (AREA)
  • Filters And Equalizers (AREA)
  • General Induction Heating (AREA)
  • Near-Field Transmission Systems (AREA)
  • Electronic Switches (AREA)
  • Magnetic Treatment Devices (AREA)

Abstract

A batteryless, portable, frequency divider includes a first resonant LC circuit (70) that is resonant at a first frequency for receiving electromagnetic radiation at the first frequency; and a second resonant LC circuit (74) that is resonant at a second frequency that is one-half the first frequency for transmitting electromagnetic radiation at the second frequency. The first circuit is coupled only magnetically to the second circuit to transfer energy to the second circuit in response to receipt by the first circuit of electromagnetic radiation at the first frequency. At least one of the resonant circuits includes a variable reactance element, such as a variable capacitance diode (D1<.>, D1<..>) or a varactor. In a variable reactance element (D1<.>) of the first circuit (70), the reactance varies with variations in energy received by the first circuit for causing the second circuit to vary in reactance due to mutual reactive coupling to cause the second circuit to transmit electromagnetic radiation at the second frequency in response to the energy transferred from the first circuit at the first frequency. In a variable reactance element (D2<.>) of the second circuit (74), the reactance varies with variations in energy transferred from the first circuit for causing the second circuit to transmit electromagnetic radiation at the second frequency in response to the energy transferred from the first circuit at the first frequency. Both resonant circuits include inductance coils (L1<.>, L2<.>) that are disposed on a ferrite rod (72), for enhancing the magnetic coupling. The frequency divider is included in a tag utilized in a presence detection system. <IMAGE>
NO91912997A 1990-08-03 1991-08-01 TABLE OF FREQUENCY PARTS. NO912997L (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US07/562,475 US5065137A (en) 1990-08-03 1990-08-03 Magnetically-coupled, two-resonant-circuit, frequency-division tag
US07/562,471 US5065138A (en) 1990-08-03 1990-08-03 Magnetically-coupled two-resonant-circuit, frequency divider for presence-detection-system tag

Publications (2)

Publication Number Publication Date
NO912997D0 NO912997D0 (en) 1991-08-01
NO912997L true NO912997L (en) 1992-02-04

Family

ID=27072966

Family Applications (1)

Application Number Title Priority Date Filing Date
NO91912997A NO912997L (en) 1990-08-03 1991-08-01 TABLE OF FREQUENCY PARTS.

Country Status (8)

Country Link
EP (1) EP0469769B1 (en)
JP (1) JP3224564B2 (en)
AT (1) ATE152848T1 (en)
AU (1) AU635654B2 (en)
CA (1) CA2047559C (en)
DE (1) DE69125985T2 (en)
ES (1) ES2100934T3 (en)
NO (1) NO912997L (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5241298A (en) * 1992-03-18 1993-08-31 Security Tag Systems, Inc. Electrically-and-magnetically-coupled, batteryless, portable, frequency divider
SE508322C2 (en) * 1994-02-07 1998-09-28 Leif Aasbrink Alarm element
GB9815118D0 (en) * 1998-07-14 1998-09-09 Clan Holdings Ltd Security tag
RU2229160C1 (en) * 2002-10-01 2004-05-20 Шалыгин Александр Николаевич Identifying mark
US7199717B2 (en) * 2004-02-17 2007-04-03 Sensormatic Electronics Corporation Frequency-division marker for an electronic article surveillance system
US10380857B1 (en) * 2018-03-05 2019-08-13 Sensormatic Electronics, LLC Systems and methods for radio frequency identification enabled deactivation of acousto-magnetic ferrite based marker

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1604219A (en) * 1977-04-28 1981-12-02 Parmeko Ltd Detection systems
US4481428A (en) * 1981-05-19 1984-11-06 Security Tag Systems, Inc. Batteryless, portable, frequency divider useful as a transponder of electromagnetic radiation
NL8204802A (en) * 1982-12-10 1984-07-02 Nedap Nv DETECTION PLATE WITH NON-LINEAR CIRCUIT FOR A DETECTION SYSTEM.
US4727360A (en) * 1985-09-13 1988-02-23 Security Tag Systems, Inc. Frequency-dividing transponder and use thereof in a presence detection system
US4670740A (en) * 1985-11-04 1987-06-02 Security Tag Systems, Inc. Portable, batteryless, frequency divider consisting of inductor and diode

Also Published As

Publication number Publication date
JP3224564B2 (en) 2001-10-29
CA2047559C (en) 1999-07-06
AU8132591A (en) 1992-02-06
AU635654B2 (en) 1993-03-25
NO912997D0 (en) 1991-08-01
EP0469769B1 (en) 1997-05-07
ATE152848T1 (en) 1997-05-15
JPH04233696A (en) 1992-08-21
DE69125985D1 (en) 1997-06-12
CA2047559A1 (en) 1992-02-04
ES2100934T3 (en) 1997-07-01
EP0469769A2 (en) 1992-02-05
DE69125985T2 (en) 1997-12-11
EP0469769A3 (en) 1992-12-30

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