EP0255812A2 - Dispositif de surveillance avec des composants détecteurs à infrarouge et à radiofréquence - Google Patents

Dispositif de surveillance avec des composants détecteurs à infrarouge et à radiofréquence Download PDF

Info

Publication number
EP0255812A2
EP0255812A2 EP87830294A EP87830294A EP0255812A2 EP 0255812 A2 EP0255812 A2 EP 0255812A2 EP 87830294 A EP87830294 A EP 87830294A EP 87830294 A EP87830294 A EP 87830294A EP 0255812 A2 EP0255812 A2 EP 0255812A2
Authority
EP
European Patent Office
Prior art keywords
radio
sensor
frequency
monitoring device
frequency sensor
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.)
Withdrawn
Application number
EP87830294A
Other languages
German (de)
English (en)
Other versions
EP0255812A3 (fr
Inventor
Luigi Bianco
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Elkron SpA
Original Assignee
Elkron SpA
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 Elkron SpA filed Critical Elkron SpA
Publication of EP0255812A2 publication Critical patent/EP0255812A2/fr
Publication of EP0255812A3 publication Critical patent/EP0255812A3/fr
Withdrawn legal-status Critical Current

Links

Images

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
    • G08B13/2491—Intrusion detection systems, i.e. where the body of an intruder causes the interference with the electromagnetic field
    • G08B13/2494—Intrusion 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
    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
    • G08B13/189—Actuation 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
    • G08B13/19—Actuation 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 using infrared-radiation detection systems

Definitions

  • the present invention relates to monitoring devices of the type designed for use in intruder alarm systems (anti-theft systems).
  • the invention relates more particularly to a monitoring device using a combination of an infrared sensor and a radio-frequency sensor.
  • PIR passive infrared sensor
  • X band 5.2-1O.9 GHz
  • Gunn diode generator acting as the generator of the wave­front for the illumination of the location to be monitored.
  • a solution of this type provides goods operat­ing results, particularly as regards the possibility of providing effective cover for the monitored location and the possibility of minimizing false alarms resulting from phenomena (rising air currents, etc.) which do not correspond to actual or attempted intrusions into the location being monitored.
  • the in­trusion alarm signal is generated only in the event of actual detection of the intrusion by both the sensors.
  • This latter aspect i.e. the identification of the combined infrared and radio-frequency operation of the device
  • accurate identification of the type of device may enable, or at least facilitate, the use of coun­termeasures by the person attempting to intrude into the location being monitored.
  • the object of the present invention is to provide a monitoring device of the above type which, while retaining unchanged the advantages of the known solutions, does not have the above-mentioned draw­backs.
  • a monitoring device which uses a combination of an infrared sensor and a radio-fre­quency sensor, characterized in that this radio-fre­quency sensor is selected with an operating frequency substantially in the UHF band, preferably a frequency of approximately 2.45 GHz.
  • this radio-frequency sensor is integrated in a UHF oscillator of the self-detect type and is provided with a strip aerial substantially co­extensive with a support structure (printed circuit board) on which there are mounted both the infrared sensor and the radio-frequency sensor and/or a board including the infrared sensor and its associated electronics, with the electronics relating to the UHF sensor and the UHF oscillator section in a modular version with a connection to the main portion.
  • a support structure printed circuit board
  • a monitoring device designed, for example, for use in an intruder alarm installation, is designated overall by 1.
  • This is more particularly a monitoring device using a combination of a passive infrared sensor (PIR) and a radio-frequency oscillator of the self-­ detect type whose function is to detect the distur­bances caused in the respective parts of the electro-­magnetic wave spectrum by the presence and movement of an intruder in a monitored location in which the device 1 is installed.
  • PIR passive infrared sensor
  • radio-frequency oscillator of the self-­ detect type whose function is to detect the distur­bances caused in the respective parts of the electro-­magnetic wave spectrum by the presence and movement of an intruder in a monitored location in which the device 1 is installed.
  • circuit structure used for the device 1 is shown in Fig. 3.
  • reference numeral 2 indicates a UHF oscillator of the self-detect type connected to a transmitting and receiving aerial 3 in a manner which will be explained in more detail below.
  • the oscillator 2 has an output line 4 connect­ed to an amplifier 5 able to amplify the signal present on the line 4.
  • this signal corresponds to the disturbance of the field of radio-frequency waves present in the location being monitored as a result of the Doppler effect produced by the movement of an intruder in this location.
  • the signal at the output of the amplifier 5, whose gain is variable and may be selected by acting on a control 5a, so as to vary the sensivity of cover (distance range) of the UHF sensor, is caused to pass through an integrator circuit 6.
  • This is more precisely a so-called delay circuit, controlled by a control circuit whose time constant may be controlled in a selective manner by acting on one or more control terminals 8 so as to regulate the sen­sivity of detection (minimum extent and duration of the event considered to be detectable) of the UHF sensor.
  • the detection signal emitted at the output of the delay circuit 6 is supplied to a circuit 9 whose function is to generate, from the detection pulse emitted by the circuit 6, a rectangular pulse whose duration may be selected in advance, for example 3-4 seconds.
  • This latter signal is supplied to a logic gate of AND type 1O with two inputs.
  • the connection of the circuit 9 to the gate 1O is formed by a jumper A inserted in a terminal board 1OO.
  • the other input of the AND-gate 1O is con­nected to a further detection branch whose input component is formed by a passive type infrared sensor 11 whose function is to detect, in a known manner, the presen­ce in the monitored location of infrared wavefronts generated by the presence of an intruder in this location.
  • the signal generated by the infrared sensor 11 is transmitted to a corresponding amplifier 12 which is connected in cascade with two circuits 14 and 15 similar in structure to the above-described circuits 6 and 9 respectively.
  • the output of the circuit 15 is connected to the logic gate 1O whose output is in turn connected to a relay control circuit 1OA which is able to cause, via the closing of a contact 1OB, the trans­mission of an alarm signal from the intruder signalling system (not shown overall) of which the device 1 is part.
  • the AND mode logic configuration - of the two detection sections (UHF and infrared) provided by the gate 1O in the diagram of Fig. 3 is designed to minimize the probability of false alarms, i.e. the probability that the relay 1OA is activated causing the transmission of the alarm signal, as a result of accidental phenomena (for example air current, penetration into the monitored location of light beams from vehicle headlights or from the torches of watchman, starting up of automatic components of domestic electrical products, etc.) not caused by the presence and movement of an intruder in the monitored location.
  • accidental phenomena for example air current, penetration into the monitored location of light beams from vehicle headlights or from the torches of watchman, starting up of automatic components of domestic electrical products, etc.
  • the relay 1OA is activated only when there is at least a partial temporal superimposition of the rectangular pulse signals generated by the circuits 9 and 15.
  • a further generator circuit similar in struc­ture to the circuit 9, connected to the output of the amplifier 5 and terminating at the terminal block 1OO is designated by 1O1.
  • the latter is arranged so that it enables, in an alternative manner: - the connection, via the jumper A, of the out­put of the circuit 9 to the respective input of the AND-gate 1O (Fig.3), or - the connection of this input to a voltage source 1O2 corresponding to a logic level "1" via a jumper B and the connection of the output of the cir­cuit 1O1 to the output of the gate 1O via a jumper C (Fig. 5).
  • This latter connection arrangement (which cor­responds in practice to the logic sum (OR) of the outputs of the circuits 1O1 and 15) may be ad­vantageously used in cases in which it is feared that there may be attempts to cover the infrared sensor 11. These attempts are usually carried out by slowly sliding a screen such as a sheet of paper or even a hand in front of the sensor.
  • connection of the first input of this gate to the logic level "1" formed by the source 1O2 in any case makes it possible to take account of an alarm signal generated by the sensor 11 if the latter is not completely masked.
  • the alarm signal from the UHF sensor is sampled upstream of the delay circuit 6 is due to the fact that, in the case of an attempt to obstruct the sensor 11, the phenomena to be detected generally evolve slowly, but produce comparatively intense blips.
  • the UHF sensor has two outputs with different level of sensitivity. The first of these, which is used when ascertaining the logic product of the signals transmitted by the two sensors (gate 1O) cor­responds to the output of the circuit 9, connected to the delay 6.
  • the second output used when ascer­taining - at the output of the gate 1O - the logic sum of the signals from both sensors, is that cor­responding to the output of the circuit 1O1, con­nected to the amplifier 5 upstream of the delay 6.
  • the salient feature of the invention lies in the fact that the self-detect oscillator 2 operates in a particular frequency range, i.e. in the UHF band (3OO-3OOO MHz) and preferably at a frequency of ap­proximately 2.45 GHz.
  • a possible embodiment of the oscillator 2 is shown by way of example in Fig. 4.
  • reference numeral 16 designates a transistor forming the core of the oscillator whose operating frequency may be tuned by acting on a capacitor 17 whose capacitance may be varied in a selective manner around 2-5 pF.
  • the collector of the transistor 16 is con­nected to the supply voltage 18 of the device 1 which may be supplied from a supply device (not shown) either from the normal electrical mains or from a floating battery to which two resistors 19 and 2O (with resistance values of 2.7 KOhm and 47O Ohm respectively) are also connected in series to the ground/terminal 21 of the oscillator.
  • a supply device not shown
  • resistors 19 and 2O with resistance values of 2.7 KOhm and 47O Ohm respectively
  • the resistor 19 is connected in parallel with a capacitor 22 having a capacitance value of ap­proximately 4-7 pF, while the intermediate connection point of the resistors 19 and 2O is connected to a coil 23 having an impedance value of approximately 1OO Ohm whose opposite terminal is connected to the base of the transistor 16.
  • the base of the transistor 16 is then connected to the aerial 3 via a connection line in which there is interposed, in addition to the tuning capacitor 17, a further coil 24 having an impedance value of approximately 5O Ohm.
  • the series of a coil 25 having an impedance value of 8O Ohm and a resistor 26 having a resistance value of 22 Ohm are connected to the emitter of the transistor 16.
  • a capacitor 27 with a capacitance of approxi­mately 4-7 pF, is connected with one terminal wire to the intermediate point of connection of the two components 25 and 26 whereas the opposite terminal wire leads to the supply line 18.
  • the terminal of the resistor 26 opposite to the terminal to which the capacitor 27 is connected acts as an output terminal of the oscillator 2 and is therefore connected to the line 4.
  • a further capacitor 28 with capacitance value of approximately 1OOO pF and a further resistor 29 with a resistance value of approximately 1OO Ohm, connected in paral­lel, are finally connected between this latter terminal, i.e. the line 4, and the earth point 21.
  • a further capacitor is finally designated by 3O and acts as a bypass capacitance for the radio-frequency between the supply line 18 and the ground point 21.
  • This latter capacitor has a capacitance value of approximately 22OO pF.
  • a printed circuit board is designated by 31, in which practically all the circuit components of Fig. 3 are mounted.
  • the whole of the oscillator may be constructed as a module inter­connected to the main board 31.
  • the board 31, shown on an actual scale in Fig. 2, is mounted within a housing 32 acting as a con­tainer for the device 1.
  • this involve the same type of container used for the in­frared radiation detection device disclosed in a prior Italian Patent Application No. 68OO9-A/85 in the name of applicants.
  • the housing 32 is substantially formed by a tray-shaped quadrangular body 33 to which there is applied a cover 34 shaped generally as a dome in which there is mounted a Fresnel lens 35.
  • the lens 35 acts as a collection element for the infrared radiation present in the monitored location and can focus this radiation on the infrared sensor 11.
  • the board 31 is mounted within the tray-shaped body 33 so that it is facing the lens with the sensor 11 mounted in a central position with respect to the board 31.
  • the reference numerals shown in Fig. 2 designate the corresponding circuit components shown in Figs. 3 and 4, i.e., in addition to the infrared sensor 11, the aerial 3 of the oscillator 2, the transistor 16 and the tuning capacitor 17 of the oscillator 2, the relay 1OA and the respective con­tacts 1OB.
  • the aerial 3 whose overall length is approximately 4 cm, is formed simply by a strip line applied (using known techniques) to the board 31 and therefore sub­stantially coextensive with the latter or, alter­natively, on the board on which the module of the UHF oscillator is mounted.
  • a monitoring device of the type described has an electrical current consumption of approximately 25-3O mA.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • General Physics & Mathematics (AREA)
  • Burglar Alarm Systems (AREA)
EP87830294A 1986-08-08 1987-07-29 Dispositif de surveillance avec des composants détecteurs à infrarouge et à radiofréquence Withdrawn EP0255812A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT67649/86A IT1195131B (it) 1986-08-08 1986-08-08 Dispositivo di sorveglianza con elementi sensori all infrarosso ed a radiofrequenza
IT6764986 1986-08-08

Publications (2)

Publication Number Publication Date
EP0255812A2 true EP0255812A2 (fr) 1988-02-10
EP0255812A3 EP0255812A3 (fr) 1989-10-18

Family

ID=11304217

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87830294A Withdrawn EP0255812A3 (fr) 1986-08-08 1987-07-29 Dispositif de surveillance avec des composants détecteurs à infrarouge et à radiofréquence

Country Status (2)

Country Link
EP (1) EP0255812A3 (fr)
IT (1) IT1195131B (fr)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995011458A1 (fr) * 1993-10-20 1995-04-27 Mader Elektronik Und Telekommunikationstechnik Gmbh Indicateur de mouvement
US5499016A (en) * 1992-02-17 1996-03-12 Aritech B.V. Intrusion alarm system
WO1997022957A1 (fr) * 1995-12-20 1997-06-26 Pyronix Limited Dispositif de detection d'evenements avec capacite de surveillance d'incident
CN106530560A (zh) * 2016-11-04 2017-03-22 广西大学 一种基于人体红外感应模块的防盗报警器
CN108564748A (zh) * 2018-07-06 2018-09-21 长春工程学院 变压器防盗报警系统

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3725888A (en) * 1971-04-05 1973-04-03 Pyrotector Inc Detector system
US3852735A (en) * 1971-08-09 1974-12-03 Modern Electronic Instr Corp Alarm apparatus utilizing high frequency
US4028690A (en) * 1976-01-29 1977-06-07 Shorrock Developments Limited Intruder detection device
GB2012092A (en) * 1978-01-06 1979-07-18 American District Telegraph Co Alarm system
EP0032593A2 (fr) * 1980-01-16 1981-07-29 Hans Günther STADELMAYR Installation d'alarme, de sécurité et de surveillance
EP0058032A2 (fr) * 1981-02-11 1982-08-18 Racal-Mesl Limited Dispositif de radar

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3725888A (en) * 1971-04-05 1973-04-03 Pyrotector Inc Detector system
US3852735A (en) * 1971-08-09 1974-12-03 Modern Electronic Instr Corp Alarm apparatus utilizing high frequency
US4028690A (en) * 1976-01-29 1977-06-07 Shorrock Developments Limited Intruder detection device
GB2012092A (en) * 1978-01-06 1979-07-18 American District Telegraph Co Alarm system
EP0032593A2 (fr) * 1980-01-16 1981-07-29 Hans Günther STADELMAYR Installation d'alarme, de sécurité et de surveillance
EP0058032A2 (fr) * 1981-02-11 1982-08-18 Racal-Mesl Limited Dispositif de radar

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5499016A (en) * 1992-02-17 1996-03-12 Aritech B.V. Intrusion alarm system
WO1995011458A1 (fr) * 1993-10-20 1995-04-27 Mader Elektronik Und Telekommunikationstechnik Gmbh Indicateur de mouvement
WO1997022957A1 (fr) * 1995-12-20 1997-06-26 Pyronix Limited Dispositif de detection d'evenements avec capacite de surveillance d'incident
US6265970B1 (en) 1995-12-20 2001-07-24 Pyronix Limited Event detection device with fault monitoring capability
CN106530560A (zh) * 2016-11-04 2017-03-22 广西大学 一种基于人体红外感应模块的防盗报警器
CN108564748A (zh) * 2018-07-06 2018-09-21 长春工程学院 变压器防盗报警系统
CN108564748B (zh) * 2018-07-06 2023-10-31 长春工程学院 变压器防盗报警系统

Also Published As

Publication number Publication date
EP0255812A3 (fr) 1989-10-18
IT8667649A0 (it) 1986-08-08
IT1195131B (it) 1988-10-12

Similar Documents

Publication Publication Date Title
US5093656A (en) Active supervision of motion-detection systems
US4099168A (en) Intrusion alarm and emergency illumination apparatus and method
US5854588A (en) Home security system for detecting an intrusion into a monitored area by an infrared detector
US4507654A (en) Security system with infrared optical position detector
US4148019A (en) Security alarm transmission system
US3691558A (en) Moving object microwave detection system
US4833450A (en) Fault detection in combination intrusion detection systems
US4996517A (en) Household alarm system
US4001805A (en) Sound activated alarm system
US3242486A (en) Intrusion detection system
US4092636A (en) Protective alarm system for window using reflected microwave energy
US5793286A (en) Combined infrasonic and infrared intrusion detection system
EP0499177A1 (fr) Dispositif de détection d'intrusion
US4361833A (en) Multi-sensor alarm system and method of protecting a premises
GB2280558A (en) Self-oscillating mixer
US6034604A (en) Deactivation prevention for electronic article surveillance systems
US4358759A (en) Microwave movement detector
US3967258A (en) Alarm system
EP0255812A2 (fr) Dispositif de surveillance avec des composants détecteurs à infrarouge et à radiofréquence
US4163968A (en) Supervised loop alarm radio transmitter system
US4241335A (en) Automatically supervised alarm system
US3914753A (en) Intruder alarm system
EP0337964A1 (fr) Dispositif de détection combinée à infrarouge et micro-ondes, en particulier pour systèmes contre l'intrusion
WO1988008595A1 (fr) Detecteur de proximite a capacitance
US5043703A (en) Supervision of autodyne microwave motion-detection system

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH DE ES FR GB GR LI LU NL SE

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH DE ES FR GB GR LI LU NL SE

17P Request for examination filed

Effective date: 19900203

17Q First examination report despatched

Effective date: 19920903

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19930316

RIN1 Information on inventor provided before grant (corrected)

Inventor name: BIANCO, LUIGI