US3725888A - Detector system - Google Patents

Detector system Download PDF

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Publication number
US3725888A
US3725888A US3725888DA US3725888A US 3725888 A US3725888 A US 3725888A US 3725888D A US3725888D A US 3725888DA US 3725888 A US3725888 A US 3725888A
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Prior art keywords
detector
alarm
signal
output
system
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Expired - Lifetime
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E Solomon
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GRAVINER Inc A CORP OF
WALTER KIDDE AEROSPACE Inc A CORP OF
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PYROTECTOR Inc
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    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00Burglar, theft or intruder alarms
    • G08B13/22Electrical actuation
    • G08B13/24Electrical actuation by interference with electromagnetic field distribution
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01SRADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/50Systems of measurement based on relative movement of target
    • G01S13/52Discriminating between fixed and moving objects or between objects moving at different speeds
    • G01S13/56Discriminating between fixed and moving objects or between objects moving at different speeds for presence detection
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00Burglar, theft or intruder alarms
    • G08B13/18Actuation by interference with heat, light or radiation of shorter wavelength; Actuation by intruding sources of heat, light or radiation of shorter wavelength
    • G08B13/189Actuation by interference with heat, light or radiation of shorter wavelength; Actuation by intruding sources of heat, light or radiation of shorter wavelength using passive radiation detection systems
    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00Burglar, theft or intruder alarms
    • G08B13/22Electrical actuation
    • G08B13/24Electrical actuation by interference with electromagnetic field distribution
    • G08B13/2491Intrusion detection systems, i.e. where the body of an intruder causes the interference with the electromagnetic field
    • G08B13/2494Intrusion detection systems, i.e. where the body of an intruder causes the interference with the electromagnetic field by interference with electro-magnetic field distribution combined with other electrical sensor means, e.g. microwave detectors combined with other sensor means

Abstract

An intruder detector system that utilizes both a Doppler effect detector system and an optical detector system monitoring the same space. An alarm output signal produced by either detector under alarm conditions is prevented from activating an alarm unless the other detector also is producing an alarm signal.

Description

36794- sss: SR ge a I: W 24514 XR anamaaa ge United States Patent 1191 1111 3,725,888 Solomon [451 Apr. 3, 1973 v S /5 [54] DETECTOR SYSTEM 3,564,529 2 1971 Kaufman et al. ..340 258 1) 9 I 3,573,8l7 4/1971 Akers ..340/258 52-; [75] Inventor Elias Duxbury Mass 3,242,486 3/1966 Corbell.... ..340/258 A [73] Assignee: Pyrotector, Incorporated, Hingham, 3,560,950 2/1971 Peters ..340/258 D Z3? Mass. fit [22] Filed. Apr 5 1971 Primary Examiner-David L. Trafton Attorney-Robert E. Ross fi a [21] Appl. No.: 131,222 )5 57 ABSTRACT [52] CL "340/258 340/258 6 An intruder detector system that utilizes both a DOP. [51] Int CL Gosh 13/16 Gosh 3/18 pler effect detector system and an optical detector Field of 3 0 25 R A, B, 25 system monitoring thfi same space. An alarm output signal produced by either detector under alarm conditions is prevented from activating an alarm unless the 5 References Cited other detector also is producing an alarm signal.

UNITED STATES PATENTS 3 Claims, 1 Drawing g r 3,010,102 11/1961 Ketchledge et al 340/228 S X ie i a 10 *1 l i T V50 C/fiCW/T I man/route)? k 5 THAAljH/ITER 2 0R, R l Tam/rowan I CE/V AMPLIFIER may I MIXER DUE-CT wrscmro/e I 1 M0 ALARM 5 N; I qA-rs ACTUATOR l AMPLIFIEQ Pl/DI'OELECTRIC 4 ms: l E R s T DISCEIMINATDR OUT, /I 0 rzcm V $/AT f I Em AND ENTRY oeuy 1 1 BACKGROUND OF THE INVENTION a. Field of the invention This invention relates to electronic intruder detection devices.

b. Description of the prior art One form of widely used device for intruder detection utilizes an accoustic generator that creates a pattern of standing waves in a space to be protected. Reflected waves are received by the detector, and if the reflected waves maintain a predetermined frequency, no alarm signal is created. However the motion of a person in the room or air currents due to heat from a fire will cause a change in the frequency received, and this change is utilized to actuate an alarm.

Another device of this type utilizes microwaves in the electro-magnetic spectrum, with the method of operation being substantially as described with respect to the acoustic system.

Although such devices have achieved considerable commercial success, they have the disadvantage of being extremely subject to false alarms from extraneous sounds from both inside and outside the protected space. For example, outside sounds such as automobile engine noises, sirens, thunder, airplanes, or construction equipment can contain sufficient high frequency components to cause an alarm response of the acoustic type of detector. Internally, sounds of thermostats or other devices with contacts, electric motors, telephones, doorbells, or the motion of animals such as cats, rodents, or guard dogs can cause an alarm response, as can air turbulence due to hot air heating systems.

In the case of the microwave type of detector, a false alarm may be caused by spurious R.F. signals or motion of a person or article in an area beyond the confined space, since the transmission passes through any wall not made of metallic material.

Although some of these causes of false alarms can often be prevented by the use of delay features in the alarm portion of the circuit, or by controlling the sensitivity of the device, such features reduce the effectiveness of the device in detecting intruders.

Another type of volumetric space surveillance system (as opposed to a line of sight type of detector) is an optical detector which utilizes the rate of change of light intensity to actuate an alarm. This type of device is also prone to false alarms, due to unpredictable sudden changes in ambient illumination such as head lights from passing cars, lightning, lightbulb failure or momentary power failure.

SUMMARY OF THE INVENTION In accordance with the present invention a detector system comprises-a Doppler effect intruder detector and a volumetric optical detection system combined to monitor the same space. The outputs of the detectors are connected to an AND gate, with the output of the AND gate being connected to alarm actuating means. Phenomena that cause false alarms in Doppler effect detectors and those that cause false alarms in optical detection are so different that the possibility is very slight that phenomena that affect each will occur simultaneously.

DESCRIPTION OF THE DRAWING The single FIGURE of the drawing is a block diagram illustrating a detector system embodying the features of the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT Asillustrated in the drawing a detector system embodying the features of the invention comprises a Doppler effect detector 10 and a photo-electric detector 12 positioned for surveillance of the same space to be protected from intruders. The detectors l0 and 12 cooperate to energize an alarm on detecting an intruder or other condition in a manner to appear herein after.

Both Doppler effect detectors and optical detectors are known in the art and the specific types of detectors to be described are by way of example only, since other types may be used without departing from the scope of the invention.

The detector 10 comprises a tuned circuit resonating at, for example, 40 kHz which drives a piezq-ele ctric tranducer transmitter, which radiates at 40 kl lz into the protected space. When the detector is in use, a

standing wave pattern of 40 kHz is established in the space, a portion of which is reflected back to the transducer, which also has a resonating frequency of 40' kHz. The output of the receiver transducer is fed into an amplifier and mixer which also receives a 40 kHz signal from the tuned circuit driver. If there is no disturbance in the ultra-sonic waves, the frequency received at the receiver transducer and therefore at the mixer is the same as the 40 kHz signal from the tuned circuit driver. However if there is any movement of a body in the protected space a different frequency is received at the receiver transducer, which when amplified and compared with the driver frequency in the mixer, produces a beat frequency. The detector allows this beat frequency to filter through to the delay integrator, which insures that the beat frequency is present for a predetermined time before transmitting a signal to the AND gate.

In the illustrated embodiment theoptical detector system 12 comprises a photo-electric detector which is positioned to receive ambient light from the same space into which the Doppler effect system 10 is transmitting, an amplifier and discriminator which receives the signal from the photo-electric detector, and an output pulse generator which feeds an alarm pulse to the AND gate.

The photo-electric devices may be photoresistive or photo-generative and may have various optical filters to make the device insensitive to light of certain band widths.

The discriminator responds to a predetermined change in illumination reaching the photo-electric detector to provide an output pulse to the AND gate.

As illustrated schematically, if the rate of change of the light received by the photo-electric detector is below a certain value, no signal is transmitted to the pulse output generator whereas if the rate of change is above said minimum value a signal is transmitted to the pulse output generator to produce an alarm pulse to the AND gate.

If both the Doppler effect detector and the optical detector provide an output signal at the same time, an output alarm signal will be transmitted to the alarm activating device, However the AND gate will not allow the alarm to be actuated if only one detector provides an output signal.

Although each detector in the above described system is subject to the false alarm conditions previously described, no single false alarm cause will cause a false alarm in both detectors simultaneously. The probability that a false alarm condition that affects the Doppler type detector will occur simultaneously with a false alarm condition that affects the optical detector, if not absolutely non-existent is very slight. The inhibiting of each detector by the other does not, however reduce the effectiveness of the detector in providing an alarm in response to an intruder.

in the illustrated embodiment of the invention, an entry and exit delay feature may be provided between the AND gateand the alarm actuating device to allow personnel time to leave the protected space after energizing the detector system, without actuating the alann, and when re-entering, to allow them time to de-energize the system before the alarm is actuated by their presence.

Since certain obvious changes may be made in the embodiment described herein, it is intended that all matter contained herein be interpreted in an illustrative and not a limiting sense.

lclaim:

1. An intruder detector system, comprising first and second detector devices arranged to monitor substantially the same confined space, each of said detector devices being responsive to the entry of an intruder to provide an output signal, one of said detectors being responsive to a Doppler effect to produce its output signal, the other being responsive to a change in light intensity to produce its output signal, means receiving the output of each of said detectors, said means producing an-alarm output signal only when said detectors produce an output signal simultaneously.

2. A detector system comprising a detection device of the type utilizing a change in frequency to cause an alarm output signal and a detector device utilizing a rate of change in light intensity to cause an alarm output signal, said detector devices being arranged to monitor substantially the same confined space, an AND gate, the output of said detectors being connected to said AND gate, the output of said AND gate being connected to an alarm actuating device, whereby the AND gate transmit a signal to the alarm actuating device only if both alarm devices produce an alarm output signal simultaneously.

3. A detector system, comprising a first detector producing an alarm signal output in response to a change in frequency between a transmitted signal and a received signal, and a second detector arranged to monitor at least a portion of a confined space being monitored by the first detector, said second detector being responsive to a predetermined change of light intensity to cause an alarm signal output, and means preventing said alarm signal output from either detector from actuating an alann unless the other detector also simultaneously generates an alarm signal output.

Claims (3)

1. An intruder detector system, comprising first and second detector devices arranged to monitor substantially the same confined space, each of said detector devices being responsive to the entry of an intruder to provide an output signal, one of said detectors being responsive to a Doppler effect to produce its output signal, the other being responsive to a change in light intensity to produce its output signal, means receiving the output of each of said detectors, said means producing an alarm output signal only when said detectors produce an output signal simultaneously.
2. A detector system comprising a detection device of the type utilizing a change in frequency to cause an alarm output signal and a detector device utilizing a rate of change in light intensity to cause an alarm output signal, said detector devices being arranged to monitor substantially the same confined space, an AND gate, the output of said detectors being connected to said AND gate, the output of said AND gate being connected to an alarm actuating device, whereby the AND gate transmit a signal to the alarm actuating device only if both alarm devices produce an alarm output signal simultaneously.
3. A detector system, comprising a first detector producing an alarm signal output in response to a change in frequency between a transmitted signal and a received signal, and a second detector arranged to monitor at least a portion of a confined space being monitored by the first detector, said second detector being responsive to a predetermined change of light intensity to cause an alarm signal output, and means preventing said alarm signal output from either detector from actuating an alarm unless the other detector also simultaneously generates an alarm signal output.
US3725888A 1971-04-05 1971-04-05 Detector system Expired - Lifetime US3725888A (en)

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DE (1) DE2216236B2 (en)
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GB (1) GB1342552A (en)

Cited By (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3801978A (en) * 1972-07-20 1974-04-02 E Systems Inc Ultrasonic-microwave doppler intrusion alarm system
US3866198A (en) * 1973-10-17 1975-02-11 Leopold Cohen Ultrasonic intrusion detection systems employing turbulence discrimination
US3898640A (en) * 1972-07-31 1975-08-05 Romen Faser Kunststoff Method and apparatus for providing space security based upon the acoustical characteristics of the space
US3922660A (en) * 1974-12-12 1975-11-25 American District Telegraph Co Volumetric intrusion alarm using both Doppler and net-change signal processing
US4010459A (en) * 1974-11-07 1977-03-01 Borge Schloger Systems for the detection of moving objects within a survey area by microwave diffraction
US4087814A (en) * 1976-11-05 1978-05-02 Ernst Spirig Intruder alarm systems
US4141091A (en) * 1976-12-10 1979-02-27 Pulvari Charles F Automated flush system
US4331952A (en) * 1980-09-22 1982-05-25 American District Telegraph Company Redundant sensor adapter
US4401976A (en) * 1980-01-16 1983-08-30 Stadelmayr Hans G Multiple sensor interconnected alarm system responsive to different variables
EP0147925A1 (en) * 1983-10-19 1985-07-10 C & K Systems, Inc. Combination infrared microwave intrusion detector
US4710750A (en) * 1986-08-05 1987-12-01 C & K Systems, Inc. Fault detecting intrusion detection device
EP0255812A2 (en) * 1986-08-08 1988-02-10 ELKRON S.p.A. Monitoring device with infrared and radio-frequency sensor components
EP0276306A1 (en) * 1986-05-16 1988-08-03 Denning Mobile Robotics, Inc. Intrusion detection system
US4833450A (en) * 1988-04-15 1989-05-23 Napco Security Systems, Inc. Fault detection in combination intrusion detection systems
DE3911180A1 (en) * 1988-04-08 1989-10-19 Matsushita Electric Works Ltd Notification device for crime prevention by means of a composite-sensor systems
EP0367402A1 (en) * 1988-09-29 1990-05-09 C & K Systems, Inc. An intrusion detection system and a method therefor
US4940967A (en) * 1989-08-31 1990-07-10 Burle Technologies, Inc. Balanced digital infrared detector circuit
US5189393A (en) * 1991-06-07 1993-02-23 The Watt Stopper Inc. Dual technology motion sensor
US5475365A (en) * 1993-01-28 1995-12-12 C & K Systems, Inc. Methods and apparatus for intrusion detection having improved immunity to false alarms
US5821642A (en) * 1996-11-04 1998-10-13 Hubbell Incorporated Arc prevention circuit for a mechanical switch
US5986357A (en) * 1997-02-04 1999-11-16 Mytech Corporation Occupancy sensor and method of operating same
US6078253A (en) * 1997-02-04 2000-06-20 Mytech Corporation Occupancy sensor and method of operating same
US6538570B1 (en) 1999-05-07 2003-03-25 Honeywell International Glass-break detector and method of alarm discrimination
US20030171669A1 (en) * 2002-03-11 2003-09-11 Kopp Keith A. MRI protector
WO2004044620A1 (en) * 2002-11-12 2004-05-27 Qinetiq Limited Ferromagnetic object detector
US20050206515A1 (en) * 2004-03-22 2005-09-22 Alexander Pakhomov Systems for protection against intruders
US20060177071A1 (en) * 2005-02-07 2006-08-10 Honeywell International, Inc. Method and system for detecting a predetermined sound event such as the sound of breaking glass
US7194209B1 (en) * 2002-09-04 2007-03-20 Xantech Corporation Interference resistant infrared extension system
US20070182581A1 (en) * 2006-02-06 2007-08-09 Cooper Technologies Company Acoustic occupancy sensor
US20070183329A1 (en) * 2006-02-06 2007-08-09 Cooper Technologies Company Networking of switchpacks
US20070182580A1 (en) * 2006-02-06 2007-08-09 Cooper Technologies Company Occupancy sensor network
WO2008061496A1 (en) 2006-11-24 2008-05-29 S.M.S. Smart Microwave Sensors Gmbh Method and radar arrangement for monitoring a monitoring area
US7411489B1 (en) 1999-12-29 2008-08-12 Cooper Wiring Devices, Inc. Self-adjusting dual technology occupancy sensor system and method
US20080272281A1 (en) * 2005-03-10 2008-11-06 Pyronix Limited Detector and Optical System
US20080316025A1 (en) * 2007-06-22 2008-12-25 Cobbinah Kofi B Sensible motion detector
US7541924B2 (en) 2006-02-06 2009-06-02 Cooper Technologies Company Infrared occupancy sensor
US20090167307A1 (en) * 2002-03-11 2009-07-02 Keith Kopp Ferromagnetic detection enhancer
US20110169629A1 (en) * 2005-02-02 2011-07-14 Pyronix Limited Detection Apparatus

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FR2433797B1 (en) * 1978-08-17 1982-06-25 Fichet Bauche
FR2527814B1 (en) * 1982-05-25 1985-03-08 Thomson Csf
GB2122004B (en) * 1982-05-27 1986-11-12 Spectronix Ltd Apparatus for detection of incoming objects
US4765244A (en) * 1983-04-15 1988-08-23 Spectronix Ltd. Apparatus for the detection and destruction of incoming objects
FR2611957B1 (en) * 1987-03-04 1994-06-03 Dreuilhe Jacqueline Radar motion detector has effect "Doppler" bivolumetrique
DE59100692D1 (en) * 1990-09-05 1994-01-20 Cerberus Ag Intrusion detector.

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US3242486A (en) * 1962-04-20 1966-03-22 Johnson Service Co Intrusion detection system
US3564529A (en) * 1965-10-21 1971-02-16 Us Navy Electrostatic field rate detector
US3560950A (en) * 1967-03-02 1971-02-02 Duane Peters Warning signal for swinging doors
US3573817A (en) * 1968-02-28 1971-04-06 North American Rockwell Monitoring system

Cited By (56)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3801978A (en) * 1972-07-20 1974-04-02 E Systems Inc Ultrasonic-microwave doppler intrusion alarm system
US3898640A (en) * 1972-07-31 1975-08-05 Romen Faser Kunststoff Method and apparatus for providing space security based upon the acoustical characteristics of the space
US3866198A (en) * 1973-10-17 1975-02-11 Leopold Cohen Ultrasonic intrusion detection systems employing turbulence discrimination
US4010459A (en) * 1974-11-07 1977-03-01 Borge Schloger Systems for the detection of moving objects within a survey area by microwave diffraction
US3922660A (en) * 1974-12-12 1975-11-25 American District Telegraph Co Volumetric intrusion alarm using both Doppler and net-change signal processing
US4087814A (en) * 1976-11-05 1978-05-02 Ernst Spirig Intruder alarm systems
US4141091A (en) * 1976-12-10 1979-02-27 Pulvari Charles F Automated flush system
US4401976A (en) * 1980-01-16 1983-08-30 Stadelmayr Hans G Multiple sensor interconnected alarm system responsive to different variables
US4331952A (en) * 1980-09-22 1982-05-25 American District Telegraph Company Redundant sensor adapter
EP0147925A1 (en) * 1983-10-19 1985-07-10 C & K Systems, Inc. Combination infrared microwave intrusion detector
EP0276306A1 (en) * 1986-05-16 1988-08-03 Denning Mobile Robotics, Inc. Intrusion detection system
EP0276306A4 (en) * 1986-05-16 1989-09-11 Denning Mobile Robotics Inc Intrusion detection system.
USRE33824E (en) * 1986-08-05 1992-02-18 Fault detecting intrusion detection device
US4710750A (en) * 1986-08-05 1987-12-01 C & K Systems, Inc. Fault detecting intrusion detection device
EP0255812A3 (en) * 1986-08-08 1989-10-18 ELKRON S.p.A. Monitoring device with infrared and radio-frequency sensor components
EP0255812A2 (en) * 1986-08-08 1988-02-10 ELKRON S.p.A. Monitoring device with infrared and radio-frequency sensor components
DE3911180A1 (en) * 1988-04-08 1989-10-19 Matsushita Electric Works Ltd Notification device for crime prevention by means of a composite-sensor systems
US4942384A (en) * 1988-04-08 1990-07-17 Matsushita Electric Works, Ltd. Composite type crime preventive sensor
US4833450A (en) * 1988-04-15 1989-05-23 Napco Security Systems, Inc. Fault detection in combination intrusion detection systems
EP0367402A1 (en) * 1988-09-29 1990-05-09 C & K Systems, Inc. An intrusion detection system and a method therefor
US4940967A (en) * 1989-08-31 1990-07-10 Burle Technologies, Inc. Balanced digital infrared detector circuit
US5189393A (en) * 1991-06-07 1993-02-23 The Watt Stopper Inc. Dual technology motion sensor
US5475365A (en) * 1993-01-28 1995-12-12 C & K Systems, Inc. Methods and apparatus for intrusion detection having improved immunity to false alarms
US5581236A (en) * 1993-01-28 1996-12-03 C & K Systems, Inc. Methods and apparatus for intrusion detection having improved immunity to false alarms
US5821642A (en) * 1996-11-04 1998-10-13 Hubbell Incorporated Arc prevention circuit for a mechanical switch
US5986357A (en) * 1997-02-04 1999-11-16 Mytech Corporation Occupancy sensor and method of operating same
US6078253A (en) * 1997-02-04 2000-06-20 Mytech Corporation Occupancy sensor and method of operating same
US6415205B1 (en) 1997-02-04 2002-07-02 Mytech Corporation Occupancy sensor and method of operating same
US6538570B1 (en) 1999-05-07 2003-03-25 Honeywell International Glass-break detector and method of alarm discrimination
US7411489B1 (en) 1999-12-29 2008-08-12 Cooper Wiring Devices, Inc. Self-adjusting dual technology occupancy sensor system and method
US8148989B2 (en) 2002-03-11 2012-04-03 Keith Kopp Ferromagnetic detection enhancer compatible with magnetic resonance
US20030171669A1 (en) * 2002-03-11 2003-09-11 Kopp Keith A. MRI protector
US20090167307A1 (en) * 2002-03-11 2009-07-02 Keith Kopp Ferromagnetic detection enhancer
US7489128B2 (en) 2002-03-11 2009-02-10 Kopp Keith A MRI protector
US7194209B1 (en) * 2002-09-04 2007-03-20 Xantech Corporation Interference resistant infrared extension system
US7113092B2 (en) 2002-11-12 2006-09-26 Qinetiq Limited Ferromagnetic object detector
WO2004044620A1 (en) * 2002-11-12 2004-05-27 Qinetiq Limited Ferromagnetic object detector
US20040135687A1 (en) * 2002-11-12 2004-07-15 Qinetiq Limited Ferromagnetic object detector
US20050206515A1 (en) * 2004-03-22 2005-09-22 Alexander Pakhomov Systems for protection against intruders
US20110169629A1 (en) * 2005-02-02 2011-07-14 Pyronix Limited Detection Apparatus
US8164437B2 (en) 2005-02-02 2012-04-24 Pyronix Limited Detection apparatus
US20060177071A1 (en) * 2005-02-07 2006-08-10 Honeywell International, Inc. Method and system for detecting a predetermined sound event such as the sound of breaking glass
US7680283B2 (en) 2005-02-07 2010-03-16 Honeywell International Inc. Method and system for detecting a predetermined sound event such as the sound of breaking glass
US8389924B2 (en) 2005-03-10 2013-03-05 Pyronix Limited Detector and optical system
US8044336B2 (en) 2005-03-10 2011-10-25 Pyronix Limited Detector and optical system
US20080272281A1 (en) * 2005-03-10 2008-11-06 Pyronix Limited Detector and Optical System
US7541924B2 (en) 2006-02-06 2009-06-02 Cooper Technologies Company Infrared occupancy sensor
US7486193B2 (en) 2006-02-06 2009-02-03 Cooper Technologies Company Occupancy sensor network
US20070182581A1 (en) * 2006-02-06 2007-08-09 Cooper Technologies Company Acoustic occupancy sensor
US7777632B2 (en) 2006-02-06 2010-08-17 Cooper Technologies Company Acoustic occupancy sensor
US20070182580A1 (en) * 2006-02-06 2007-08-09 Cooper Technologies Company Occupancy sensor network
US20070183329A1 (en) * 2006-02-06 2007-08-09 Cooper Technologies Company Networking of switchpacks
WO2008061496A1 (en) 2006-11-24 2008-05-29 S.M.S. Smart Microwave Sensors Gmbh Method and radar arrangement for monitoring a monitoring area
US20100103021A1 (en) * 2006-11-24 2010-04-29 Ralph Mende Method and radar arrangement for monitoring a monitoring area
US8063375B2 (en) * 2007-06-22 2011-11-22 Intel-Ge Care Innovations Llc Sensible motion detector
US20080316025A1 (en) * 2007-06-22 2008-12-25 Cobbinah Kofi B Sensible motion detector

Also Published As

Publication number Publication date Type
DE2216236A1 (en) 1972-10-12 application
BE781069A (en) 1972-07-17 grant
GB1342552A (en) 1974-01-03 application
FR2131997A1 (en) 1972-11-17 application
BE781069A1 (en) grant
DE2216236B2 (en) 1977-12-29 application
FR2131997B1 (en) 1977-07-15 grant

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