GB1440398A - Reuduction of false alarms in electronic theft-detection systems - Google Patents
Reuduction of false alarms in electronic theft-detection systemsInfo
- Publication number
- GB1440398A GB1440398A GB1430274A GB1430274A GB1440398A GB 1440398 A GB1440398 A GB 1440398A GB 1430274 A GB1430274 A GB 1430274A GB 1430274 A GB1430274 A GB 1430274A GB 1440398 A GB1440398 A GB 1440398A
- Authority
- GB
- United Kingdom
- Prior art keywords
- frequency
- transmitter
- alarm
- range
- gate
- 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.)
- Expired
Links
- 238000001514 detection method Methods 0.000 title 1
- 230000002401 inhibitory effect Effects 0.000 abstract 1
- 230000001960 triggered effect Effects 0.000 abstract 1
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
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Automation & Control Theory (AREA)
- Computer Security & Cryptography (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Signal Processing (AREA)
- Burglar Alarm Systems (AREA)
- Geophysics And Detection Of Objects (AREA)
Abstract
1440398 Theft alarms KNOGO CORP 1 April 1974 [13 April 1973] 14302/74 Heading G4N [Also in Division H4] In a theft alarm of the type in which a responder on an article to be protected responds to the field of a transmitter in the protected area by modifying the field or reradiating at a different frequency, false operation due to spurious signals is reduced by inhibiting the receiver detecting the response when it receives signals differing in frequency from that from the responder. In Fig. 3 the frequency of the transmitter is periodically swept over a range and the responders are resonant within part of the range to produce a dip in the radiated field. At the receiver the signal picked up on the antenna is passed through a filter 70 tuned to the sweep repetition frequency and a gate 76 to the alarm 80. A monostable circuit 88 triggered at each sweep, opens the gate while the frequency sweeps through the frequency range of the responders and outside that range opens a "noise" gate 74 so that any signal above a threshold level triggers a device 94 which holds gate closed during the next sweep. In Fig. 2 (not shown) the responder responds to the field of a fixed frequency transmitter by radiating signal of different frequency and this operates an alarm at the receiver if the alarm channel is not blocked by the concurrent receipt of a signal of a frequency different from the transmitter and reradiation.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US351019A US3868669A (en) | 1973-04-13 | 1973-04-13 | Reduction of false alarms in electronic theft detection systems |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1440398A true GB1440398A (en) | 1976-06-23 |
Family
ID=23379246
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB1430274A Expired GB1440398A (en) | 1973-04-13 | 1974-04-01 | Reuduction of false alarms in electronic theft-detection systems |
Country Status (12)
Country | Link |
---|---|
US (1) | US3868669A (en) |
JP (1) | JPS5752637B2 (en) |
AU (1) | AU474729B2 (en) |
BE (1) | BE813708A (en) |
CA (1) | CA1023034A (en) |
DE (1) | DE2417928C3 (en) |
FR (1) | FR2228258B1 (en) |
GB (1) | GB1440398A (en) |
IT (1) | IT1018645B (en) |
NL (2) | NL161904B (en) |
SE (1) | SE397145B (en) |
ZA (1) | ZA742089B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2489001A1 (en) * | 1980-08-21 | 1982-02-26 | Knogo Corp | METHOD AND DEVICE FOR ELECTRONIC DETECTION OF ARTICLE FLIGHTS |
US5459451A (en) * | 1993-03-12 | 1995-10-17 | Esselte Meto International Gmbh | Electronic article surveillance system with enhanced geometric arrangement |
Families Citing this family (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4063230A (en) * | 1975-06-12 | 1977-12-13 | The Magnavox Company | Balanced field theft detection system |
US4016553A (en) * | 1975-06-27 | 1977-04-05 | Knogo Corporation | Article detection system with near field electromagnetic wave control |
US4045778A (en) * | 1976-02-23 | 1977-08-30 | Wagner Electric Corporation | Dual channel wide-band frequency modulated keyable control circuit and keying circuit therefor |
US4095214A (en) * | 1976-06-17 | 1978-06-13 | Knogo Corporation | Electronic monitoring system and responder device |
US4117466A (en) * | 1977-03-14 | 1978-09-26 | Lichtblau G J | Beat frequency interference rejection circuit |
NL7708012A (en) * | 1977-07-19 | 1979-01-23 | Nedap Nv | DETECTION SYSTEM. |
US4135184A (en) * | 1977-08-31 | 1979-01-16 | Knogo Corporation | Electronic theft detection system for monitoring wide passageways |
ZA7994B (en) * | 1978-01-11 | 1980-01-30 | Tag Radionics Ltd | Presence sensing system |
DK145169C (en) * | 1978-08-09 | 1983-02-21 | Security Prod Int | PLANT FOR REGISTERING A PASSAGE OF AN OBJECT THROUGH A PRESERVED AREA |
CA1145015A (en) * | 1979-05-18 | 1983-04-19 | James H. Stephen | Surveillance systems |
US4532511A (en) * | 1979-10-12 | 1985-07-30 | Lemelson Jerome H | Automatic vehicle identification system and method |
US4281321A (en) * | 1980-06-09 | 1981-07-28 | Sensormatic Electronics Corporation | Surveillance system employing a floor mat radiator |
US4481428A (en) * | 1981-05-19 | 1984-11-06 | Security Tag Systems, Inc. | Batteryless, portable, frequency divider useful as a transponder of electromagnetic radiation |
USRE32627E (en) * | 1981-09-10 | 1988-03-22 | Sensormatic Electronics Corporation | Electrical surveillance apparatus with moveable antenna elements |
NL8202951A (en) * | 1982-07-21 | 1984-02-16 | Nedap Nv | ABSORPTION DETECTION SYSTEM. |
US4623877A (en) | 1983-06-30 | 1986-11-18 | Knogo Corporation | Method and apparatus for detection of targets in an interrogation zone |
NL8600738A (en) * | 1986-03-24 | 1987-10-16 | Nedap Nv | Suppression of false alarms due to touch. |
US4794470A (en) * | 1986-06-25 | 1988-12-27 | Media Security Incorporated And Associates | Security system for protecting information |
US4812822A (en) * | 1987-08-31 | 1989-03-14 | Monarch Marking Systems, Inc. | Electronic article surveillance system utilizing synchronous integration |
NL9100026A (en) * | 1991-01-09 | 1992-08-03 | Texas Instruments Holland | INTERESTING STATION FOR IDENTIFYING OBJECTS PROCESSED OVER A TRANSPORTATION TRACK. |
NL9100110A (en) * | 1991-01-23 | 1992-08-17 | Texas Instruments Holland | INTERESTING STATION FOR IDENTIFICATION PURPOSES WITH SEPARATE TRANSMITTER AND RECEIVER ANTENNAS. |
NL9100111A (en) * | 1991-01-23 | 1992-08-17 | Texas Instruments Holland | ANTENNA SYSTEM FOR AN INQUIRY STATION FOR IDENTIFYING OBJECTS. |
US5349332A (en) * | 1992-10-13 | 1994-09-20 | Sensormatic Electronics Corportion | EAS system with requency hopping |
EP0723692A4 (en) * | 1993-10-05 | 1997-05-28 | Pac Scan Inc | Retail theft prevention and information device |
US5661470A (en) * | 1994-03-04 | 1997-08-26 | Karr; Gerald S. | Object recognition system |
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 |
US5825291A (en) * | 1996-04-10 | 1998-10-20 | Sentry Technology Corporation | Electronic article surveillance system |
US5790031A (en) * | 1997-01-13 | 1998-08-04 | Trw Inc. | Apparatus and method for sensing a rearward facing child seat with error detection |
US5990791A (en) * | 1997-10-22 | 1999-11-23 | William B. Spargur | Anti-theft detection system |
FR2828016B1 (en) * | 2001-07-30 | 2005-03-25 | Pygmalyon | ANTENNAS OF THE TYPE LOOP |
US10726711B2 (en) | 2017-05-01 | 2020-07-28 | Johnson Controls Technology Company | Building security system with user presentation for false alarm reduction |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2794974A (en) * | 1955-01-24 | 1957-06-04 | Kidde & Co Walter | Compensation for turbulence and other efects in intruder detection systems |
US3218556A (en) * | 1963-03-29 | 1965-11-16 | Sierra Research Corp | Spectrum centered receiver |
US3577136A (en) * | 1967-08-04 | 1971-05-04 | Security Systems Inc | Short-range signaling system |
US3465336A (en) * | 1968-05-09 | 1969-09-02 | Us Army | Doppler radar with clutter controlled filter channel |
US3696379A (en) * | 1970-12-02 | 1972-10-03 | Knogo Corp | Apparatus for article theft detection |
US3711848A (en) * | 1971-02-10 | 1973-01-16 | I D Eng Inc | Method of and apparatus for the detection of stolen articles |
US3801977A (en) * | 1971-12-07 | 1974-04-02 | Gulf & Western Mfg Co | Ultrasonic alarm circuit |
US3781860A (en) * | 1972-02-14 | 1973-12-25 | Williamson W | Method and apparatus for inhibiting article theft |
-
0
- NL NLAANVRAGE7404466,A patent/NL161904C/en active
-
1973
- 1973-04-13 US US351019A patent/US3868669A/en not_active Expired - Lifetime
-
1974
- 1974-03-27 CA CA196,105A patent/CA1023034A/en not_active Expired
- 1974-04-01 AU AU67407/74A patent/AU474729B2/en not_active Expired
- 1974-04-01 GB GB1430274A patent/GB1440398A/en not_active Expired
- 1974-04-02 ZA ZA00742089A patent/ZA742089B/en unknown
- 1974-04-02 NL NL7404466.A patent/NL161904B/en not_active IP Right Cessation
- 1974-04-05 IT IT50160/74A patent/IT1018645B/en active
- 1974-04-10 SE SE7404939A patent/SE397145B/en unknown
- 1974-04-11 FR FR7412855A patent/FR2228258B1/fr not_active Expired
- 1974-04-11 DE DE2417928A patent/DE2417928C3/en not_active Expired
- 1974-04-12 BE BE143198A patent/BE813708A/en not_active IP Right Cessation
- 1974-04-13 JP JP49041610A patent/JPS5752637B2/ja not_active Expired
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2489001A1 (en) * | 1980-08-21 | 1982-02-26 | Knogo Corp | METHOD AND DEVICE FOR ELECTRONIC DETECTION OF ARTICLE FLIGHTS |
US5459451A (en) * | 1993-03-12 | 1995-10-17 | Esselte Meto International Gmbh | Electronic article surveillance system with enhanced geometric arrangement |
Also Published As
Publication number | Publication date |
---|---|
CA1023034A (en) | 1977-12-20 |
ZA742089B (en) | 1975-04-30 |
DE2417928A1 (en) | 1974-10-24 |
FR2228258B1 (en) | 1981-05-22 |
DE2417928C3 (en) | 1978-06-15 |
SE397145B (en) | 1977-10-17 |
BE813708A (en) | 1974-10-14 |
FR2228258A1 (en) | 1974-11-29 |
US3868669A (en) | 1975-02-25 |
JPS5752637B2 (en) | 1982-11-09 |
DE2417928B2 (en) | 1977-10-27 |
AU6740774A (en) | 1975-10-02 |
NL161904C (en) | |
NL7404466A (en) | 1974-10-15 |
JPS5010600A (en) | 1975-02-03 |
AU474729B2 (en) | 1976-07-29 |
IT1018645B (en) | 1977-10-20 |
NL161904B (en) | 1979-10-15 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |