CA2059665A1 - Periodic pulse discrimination system - Google Patents
Periodic pulse discrimination systemInfo
- Publication number
- CA2059665A1 CA2059665A1 CA2059665A CA2059665A CA2059665A1 CA 2059665 A1 CA2059665 A1 CA 2059665A1 CA 2059665 A CA2059665 A CA 2059665A CA 2059665 A CA2059665 A CA 2059665A CA 2059665 A1 CA2059665 A1 CA 2059665A1
- Authority
- CA
- Canada
- Prior art keywords
- periodicity
- pulses
- time period
- discrimination system
- periodic
- Prior art date
- Legal status (The legal status 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 status listed.)
- Granted
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
- G08B13/2477—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
Abstract
A periodic pulse discrimination system (10) particularly suitable for use with electronic article surveillance systems is capable of detecting valid tag pulses while discriminating against periodic pulses caused by resonances and interfering carriers as well as random noise. Circuitry that determines the periodicity of a pulse signal and is responsive to amplitude differences between successive detected pulses controls an adaptive threshold and sampling window (30) to discriminate against signals having an incorrect periodicity and an inadequate envelope rise time. A notch circuit (42) notches out pulse trains that have the correct or substantially correct periodicity but persist for a longer time period than the time period required for a tag to pass through the detection zone.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US07/530,900 US5300922A (en) | 1990-05-29 | 1990-05-29 | Swept frequency electronic article surveillance system having enhanced facility for tag signal detection |
US530,900 | 1990-05-29 | ||
PCT/US1991/002833 WO1991019278A1 (en) | 1990-05-29 | 1991-04-29 | Periodic pulse discrimination system |
Publications (2)
Publication Number | Publication Date |
---|---|
CA2059665A1 true CA2059665A1 (en) | 1991-11-30 |
CA2059665C CA2059665C (en) | 2000-03-21 |
Family
ID=24115443
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CA002059665A Expired - Fee Related CA2059665C (en) | 1990-05-29 | 1991-04-29 | Periodic pulse discrimination system |
Country Status (9)
Country | Link |
---|---|
US (2) | US5300922A (en) |
EP (1) | EP0485552B1 (en) |
AT (1) | ATE163789T1 (en) |
AU (1) | AU649450B2 (en) |
CA (1) | CA2059665C (en) |
DE (1) | DE69129002T2 (en) |
ES (1) | ES2113883T3 (en) |
HK (1) | HK1005919A1 (en) |
WO (1) | WO1991019278A1 (en) |
Families Citing this family (86)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5349339A (en) * | 1992-04-07 | 1994-09-20 | Actron Entwicklungs Ag | Apparatus for the detection of labels employing subtraction of background signals |
US5264829A (en) * | 1992-06-15 | 1993-11-23 | Knogo Corporation | Method and apparatus for theft detection using digital signal processing |
US5349332A (en) * | 1992-10-13 | 1994-09-20 | Sensormatic Electronics Corportion | EAS system with requency hopping |
SE9401450L (en) * | 1994-04-26 | 1995-10-27 | Rso Corp | Method of detecting magnetic elements |
SE9401448L (en) * | 1994-04-26 | 1995-10-27 | Rso Corp | Methods and apparatus for excitation and detection of magnetic elements |
SE9401449L (en) * | 1994-04-26 | 1995-10-27 | Rso Corp | Methods and apparatus for encoding electronic labels |
SE9401436L (en) * | 1994-04-26 | 1995-10-27 | Rso Corp | Amorphous bands with improved properties |
US5512878A (en) * | 1994-10-06 | 1996-04-30 | Sensormatic Electronics Corporation | Pulsed electronic article surveillance systems |
SE503526C2 (en) * | 1994-10-26 | 1996-07-01 | Rso Corp | Ways of detecting labels with amorphous magnetoelastic bands |
CN1184547A (en) * | 1995-04-07 | 1998-06-10 | 美国3M公司 | Electronic article surveillance system with adaptative filtering and digital detection |
DE19514601A1 (en) * | 1995-04-20 | 1996-10-24 | Esselte Meto Int Gmbh | System for electronic article monitoring, especially for the detection of resonant circuits with very different resonance frequencies |
AU710682B2 (en) * | 1995-05-17 | 1999-09-30 | Chamberlain Group, Inc., The | Rolling code security system |
US5973597A (en) * | 1996-08-27 | 1999-10-26 | Maspro Denkoh, Co., Ltd. | Theft checking system |
DE19644927A1 (en) * | 1996-10-29 | 1998-04-30 | Esselte Meto Int Gmbh | Device for monitoring an electronic security element in an interrogation zone |
US5745039A (en) * | 1997-02-21 | 1998-04-28 | Minnesota Mining And Manufacturing Company | Remote sterilization monitor |
US5926093A (en) * | 1997-08-15 | 1999-07-20 | Checkpoint Systems, Inc. | Drive circuit for reactive loads |
US5990791A (en) * | 1997-10-22 | 1999-11-23 | William B. Spargur | Anti-theft detection system |
US5973606A (en) * | 1997-12-08 | 1999-10-26 | Sensormatic Electronics Corporation | Activation/deactivation system and method for electronic article surveillance markers for use on a conveyor |
US5955992A (en) * | 1998-02-12 | 1999-09-21 | Shattil; Steve J. | Frequency-shifted feedback cavity used as a phased array antenna controller and carrier interference multiple access spread-spectrum transmitter |
US7430257B1 (en) * | 1998-02-12 | 2008-09-30 | Lot 41 Acquisition Foundation, Llc | Multicarrier sub-layer for direct sequence channel and multiple-access coding |
US6028518A (en) * | 1998-06-04 | 2000-02-22 | Checkpoint Systems, Inc. | System for verifying attachment of an EAS marker to an article after tagging |
US6338028B1 (en) * | 1998-06-11 | 2002-01-08 | Trw Inc. | Ultrasonic sensor system and method having input capture for echo processing |
WO2000016283A1 (en) * | 1998-09-11 | 2000-03-23 | Motorola Inc. | Generation of electrostatic voltage potentials for rfid/eas using piezoelectric crystals |
US6339377B1 (en) * | 1998-11-24 | 2002-01-15 | Kojin Co., Ltd. | Article surveillance security system with self-alarm |
US6133829A (en) * | 1999-03-05 | 2000-10-17 | Frl, Inc. | Walk-through metal detector system and method |
US6249229B1 (en) * | 1999-08-16 | 2001-06-19 | Checkpoint Systems, Inc., A Corp. Of Pennsylvania | Electronic article security system employing variable time shifts |
US7406261B2 (en) * | 1999-11-02 | 2008-07-29 | Lot 41 Acquisition Foundation, Llc | Unified multi-carrier framework for multiple-access technologies |
US8670390B2 (en) | 2000-11-22 | 2014-03-11 | Genghiscomm Holdings, LLC | Cooperative beam-forming in wireless networks |
KR20030011069A (en) * | 2000-12-15 | 2003-02-06 | 이스턴 리본 앤 롤 콥. | Paper roll anti-theft protection |
US6634959B2 (en) * | 2001-01-05 | 2003-10-21 | Oblon, Spivak, Mcclelland, Maier & Neustadt, P.C. | Golf ball locator |
AU2002306820B2 (en) * | 2001-03-26 | 2006-05-18 | Sensormatic Electronics Llc | Digital detection filters for electronic articles surveillance |
US10425135B2 (en) | 2001-04-26 | 2019-09-24 | Genghiscomm Holdings, LLC | Coordinated multipoint systems |
US9819449B2 (en) | 2002-05-14 | 2017-11-14 | Genghiscomm Holdings, LLC | Cooperative subspace demultiplexing in content delivery networks |
US10355720B2 (en) | 2001-04-26 | 2019-07-16 | Genghiscomm Holdings, LLC | Distributed software-defined radio |
US10931338B2 (en) | 2001-04-26 | 2021-02-23 | Genghiscomm Holdings, LLC | Coordinated multipoint systems |
US9893774B2 (en) | 2001-04-26 | 2018-02-13 | Genghiscomm Holdings, LLC | Cloud radio access network |
EP1288841A1 (en) * | 2001-08-30 | 2003-03-05 | Motorola, Inc. | Passive response communication system |
EP1493134B1 (en) * | 2002-04-11 | 2019-06-19 | Sensormatic Electronics, LLC | System and method for optimizing range of an electronic article surveillance system |
US6750768B2 (en) * | 2002-04-15 | 2004-06-15 | Wg Security Products, Inc. | EAS system employing pseudorandom coding system and method |
US6753821B2 (en) * | 2002-04-22 | 2004-06-22 | Wg Security Products, Inc. | Method and arrangement of antenna system of EAS |
US6745852B2 (en) * | 2002-05-08 | 2004-06-08 | Anadarko Petroleum Corporation | Platform for drilling oil and gas wells in arctic, inaccessible, or environmentally sensitive locations |
US9628231B2 (en) | 2002-05-14 | 2017-04-18 | Genghiscomm Holdings, LLC | Spreading and precoding in OFDM |
US10142082B1 (en) | 2002-05-14 | 2018-11-27 | Genghiscomm Holdings, LLC | Pre-coding in OFDM |
US10200227B2 (en) | 2002-05-14 | 2019-02-05 | Genghiscomm Holdings, LLC | Pre-coding in multi-user MIMO |
US10644916B1 (en) | 2002-05-14 | 2020-05-05 | Genghiscomm Holdings, LLC | Spreading and precoding in OFDM |
US7704346B2 (en) * | 2004-02-23 | 2010-04-27 | Checkpoint Systems, Inc. | Method of fabricating a security tag in an integrated surface processing system |
US7116227B2 (en) * | 2004-02-23 | 2006-10-03 | Checkpoint Systems, Inc. | Tag having patterned circuit elements and a process for making same |
US8099335B2 (en) * | 2004-02-23 | 2012-01-17 | Checkpoint Systems, Inc. | Method and system for determining billing information in a tag fabrication process |
US7384496B2 (en) | 2004-02-23 | 2008-06-10 | Checkpoint Systems, Inc. | Security tag system for fabricating a tag including an integrated surface processing system |
US7138919B2 (en) * | 2004-02-23 | 2006-11-21 | Checkpoint Systems, Inc. | Identification marking and method for applying the identification marking to an item |
US7119685B2 (en) * | 2004-02-23 | 2006-10-10 | Checkpoint Systems, Inc. | Method for aligning capacitor plates in a security tag and a capacitor formed thereby |
US11381285B1 (en) | 2004-08-02 | 2022-07-05 | Genghiscomm Holdings, LLC | Transmit pre-coding |
US11184037B1 (en) | 2004-08-02 | 2021-11-23 | Genghiscomm Holdings, LLC | Demodulating and decoding carrier interferometry signals |
US11552737B1 (en) | 2004-08-02 | 2023-01-10 | Genghiscomm Holdings, LLC | Cooperative MIMO |
EP1812911A1 (en) * | 2004-11-18 | 2007-08-01 | Sensormatic Electronics Corporation | Eas reader detecting eas function from rfid device |
US9148409B2 (en) | 2005-06-30 | 2015-09-29 | The Chamberlain Group, Inc. | Method and apparatus to facilitate message transmission and reception using different transmission characteristics |
US8422667B2 (en) | 2005-01-27 | 2013-04-16 | The Chamberlain Group, Inc. | Method and apparatus to facilitate transmission of an encrypted rolling code |
US7689195B2 (en) * | 2005-02-22 | 2010-03-30 | Broadcom Corporation | Multi-protocol radio frequency identification transponder tranceiver |
WO2006112608A1 (en) * | 2005-03-14 | 2006-10-26 | Samsung Electronics Co., Ltd. | Portable device for caching rf-id tag data and method thereof |
US7825822B2 (en) | 2005-04-01 | 2010-11-02 | Cepia, Llc | System and method for extracting and conveying modulated AC signal information |
US9280692B2 (en) * | 2005-08-25 | 2016-03-08 | Nxp B.V. | Method and RFID reader for evaluating a data stream signal in respect of data and/or collision |
US7817015B1 (en) * | 2005-09-29 | 2010-10-19 | Tc License Ltd. | Floating threshold for data detection in a RFID tag |
US7663489B2 (en) * | 2006-04-28 | 2010-02-16 | Checkpoint Systems, Inc. | Alarm systems, wireless alarm devices, and article security methods |
FR2905493B1 (en) * | 2006-08-31 | 2008-12-05 | Nbg Id Soc Par Actions Simplif | AUTOMATED SYSTEM FOR REALIZING LOCALIZED INVENTORIES |
US20080079543A1 (en) * | 2006-09-14 | 2008-04-03 | Bruno Fabre | Apparatus for identifying and counting articles in bulk |
US8207826B2 (en) * | 2006-10-03 | 2012-06-26 | Ncr Corporation | Methods and apparatus for analyzing signal conditions affecting operation of an RFID communication device |
US20090066496A1 (en) * | 2007-09-11 | 2009-03-12 | Lear Corporation | Low frequency receiver for a tire pressure monitor system |
JP2010193598A (en) * | 2009-02-17 | 2010-09-02 | Nippon Soken Inc | Noncontact power supply facility and noncontact power supply system |
CA2876842A1 (en) * | 2012-06-18 | 2013-12-27 | Master Lock Company | Rfid detection system |
US9595177B2 (en) | 2014-12-14 | 2017-03-14 | Wg Security Products, Inc. | Noise compensating EAS antenna system |
CN106656073A (en) * | 2016-10-28 | 2017-05-10 | 中州大学 | Sensor electronic signal amplifier |
CN108363932B (en) | 2017-01-26 | 2023-04-18 | 手持产品公司 | Method for reading bar code and deactivating electronic anti-theft label of commodity |
WO2018184231A1 (en) | 2017-04-07 | 2018-10-11 | SZ DJI Technology Co., Ltd. | Jamming device and jamming method |
US10393784B2 (en) | 2017-04-26 | 2019-08-27 | Raytheon Company | Analysis of a radio-frequency environment utilizing pulse masking |
US10243773B1 (en) | 2017-06-30 | 2019-03-26 | Genghiscomm Holdings, LLC | Efficient peak-to-average-power reduction for OFDM and MIMO-OFDM |
US10637705B1 (en) | 2017-05-25 | 2020-04-28 | Genghiscomm Holdings, LLC | Peak-to-average-power reduction for OFDM multiple access |
US10154885B1 (en) | 2017-05-26 | 2018-12-18 | Medline Industries, Inc. | Systems, apparatus and methods for continuously tracking medical items throughout a procedure |
US10652743B2 (en) | 2017-12-21 | 2020-05-12 | The Chamberlain Group, Inc. | Security system for a moveable barrier operator |
US11074773B1 (en) | 2018-06-27 | 2021-07-27 | The Chamberlain Group, Inc. | Network-based control of movable barrier operators for autonomous vehicles |
US11423717B2 (en) | 2018-08-01 | 2022-08-23 | The Chamberlain Group Llc | Movable barrier operator and transmitter pairing over a network |
CN113454964A (en) | 2019-01-25 | 2021-09-28 | 珍吉斯科姆控股有限责任公司 | Orthogonal and non-orthogonal multiple access |
US11917604B2 (en) | 2019-01-25 | 2024-02-27 | Tybalt, Llc | Orthogonal multiple access and non-orthogonal multiple access |
US11343823B2 (en) | 2020-08-16 | 2022-05-24 | Tybalt, Llc | Orthogonal multiple access and non-orthogonal multiple access |
US11617625B2 (en) | 2019-03-12 | 2023-04-04 | Medline Industries, Lp | Systems, apparatus and methods for properly locating items |
US10997810B2 (en) | 2019-05-16 | 2021-05-04 | The Chamberlain Group, Inc. | In-vehicle transmitter training |
WO2020242898A1 (en) | 2019-05-26 | 2020-12-03 | Genghiscomm Holdings, LLC | Non-orthogonal multiple access |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3818472A (en) * | 1972-05-26 | 1974-06-18 | K Mauk | R.f. system for detecting unauthorized travel of articles through a selected zone |
US3967161A (en) * | 1972-06-14 | 1976-06-29 | Lichtblau G J | A multi-frequency resonant tag circuit for use with an electronic security system having improved noise discrimination |
US4168496A (en) * | 1977-10-05 | 1979-09-18 | Lichtblau G J | Quasi-stationary noise cancellation system |
US4300183A (en) * | 1980-03-27 | 1981-11-10 | Richardson Robert H | Method and apparatus for generating alternating magnetic fields to produce harmonic signals from a metallic strip |
US4429302A (en) * | 1981-10-08 | 1984-01-31 | I. D. Engineering, Inc. | Electronic security system with noise rejection |
CA1234892A (en) * | 1984-02-16 | 1988-04-05 | Pierre Taillefer | Security tag detection system |
US4779077A (en) * | 1987-04-13 | 1988-10-18 | Lichtblau G J | Continuously armed high reliability pulse train processor |
US4906973A (en) * | 1988-04-29 | 1990-03-06 | White's Electronics, Inc. | Walk-through metal detector |
US4888579A (en) * | 1988-09-16 | 1989-12-19 | Minnesota Mining And Manufacturing Company | False alarm minimization and direction determination methods |
US5103209A (en) * | 1989-01-09 | 1992-04-07 | Checkpoint Systems, Inc. | Electronic article surveillance system with improved differentiation |
JPH03503219A (en) * | 1989-01-09 | 1991-07-18 | チエツクポイント・システムズ・インコーポレーテツド | Electronic Article Surveillance System with Improved Discrimination |
-
1990
- 1990-05-29 US US07/530,900 patent/US5300922A/en not_active Expired - Fee Related
-
1991
- 1991-04-29 WO PCT/US1991/002833 patent/WO1991019278A1/en active IP Right Grant
- 1991-04-29 DE DE69129002T patent/DE69129002T2/en not_active Expired - Fee Related
- 1991-04-29 AT AT91909560T patent/ATE163789T1/en active
- 1991-04-29 EP EP91909560A patent/EP0485552B1/en not_active Expired - Lifetime
- 1991-04-29 ES ES91909560T patent/ES2113883T3/en not_active Expired - Lifetime
- 1991-04-29 CA CA002059665A patent/CA2059665C/en not_active Expired - Fee Related
- 1991-04-29 AU AU78760/91A patent/AU649450B2/en not_active Ceased
-
1993
- 1993-06-16 US US08/078,457 patent/US5463376A/en not_active Expired - Fee Related
-
1998
- 1998-06-05 HK HK98104976A patent/HK1005919A1/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
DE69129002T2 (en) | 1998-09-17 |
ATE163789T1 (en) | 1998-03-15 |
EP0485552A1 (en) | 1992-05-20 |
AU649450B2 (en) | 1994-05-26 |
EP0485552A4 (en) | 1992-10-28 |
WO1991019278A1 (en) | 1991-12-12 |
US5300922A (en) | 1994-04-05 |
US5463376A (en) | 1995-10-31 |
EP0485552B1 (en) | 1998-03-04 |
DE69129002D1 (en) | 1998-04-09 |
CA2059665C (en) | 2000-03-21 |
AU7876091A (en) | 1991-12-31 |
ES2113883T3 (en) | 1998-05-16 |
HK1005919A1 (en) | 1999-01-29 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
EEER | Examination request | ||
MKLA | Lapsed |