WO2012023087A1 - Système de radars multiples - Google Patents

Système de radars multiples Download PDF

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Publication number
WO2012023087A1
WO2012023087A1 PCT/IB2011/053553 IB2011053553W WO2012023087A1 WO 2012023087 A1 WO2012023087 A1 WO 2012023087A1 IB 2011053553 W IB2011053553 W IB 2011053553W WO 2012023087 A1 WO2012023087 A1 WO 2012023087A1
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WO
WIPO (PCT)
Prior art keywords
frequency
radar
radar unit
units
detection
Prior art date
Application number
PCT/IB2011/053553
Other languages
English (en)
Inventor
Paulus Thomas Maria Van Zeijl
Henricus Theodorus Van Der Zanden
Original Assignee
Koninklijke Philips Electronics N.V.
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 Koninklijke Philips Electronics N.V. filed Critical Koninklijke Philips Electronics N.V.
Publication of WO2012023087A1 publication Critical patent/WO2012023087A1/fr

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO 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
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/023—Interference mitigation, e.g. reducing or avoiding non-intentional interference with other HF-transmitters, base station transmitters for mobile communication or other radar systems, e.g. using electro-magnetic interference [EMI] reduction techniques
    • G01S7/0232—Avoidance by frequency multiplex
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO 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
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/023—Interference mitigation, e.g. reducing or avoiding non-intentional interference with other HF-transmitters, base station transmitters for mobile communication or other radar systems, e.g. using electro-magnetic interference [EMI] reduction techniques
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO 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
    • G01S13/00—Systems 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
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/50—Systems of measurement based on relative movement of target
    • G01S13/52—Discriminating between fixed and moving objects or between objects moving at different speeds
    • G01S13/56—Discriminating between fixed and moving objects or between objects moving at different speeds for presence detection
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO 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
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/003—Transmission of data between radar, sonar or lidar systems and remote stations
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO 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
    • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
    • G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
    • G01S7/40—Means for monitoring or calibrating
    • G01S7/4004—Means for monitoring or calibrating of parts of a radar system
    • G01S7/4008—Means for monitoring or calibrating of parts of a radar system of transmitters
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/54—Systems for transmission via power distribution lines
    • H04B3/544—Setting up communications; Call and signalling arrangements
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
    • H05B47/10—Controlling the light source
    • H05B47/105—Controlling the light source in response to determined parameters
    • H05B47/115—Controlling the light source in response to determined parameters by determining the presence or movement of objects or living beings
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B47/00—Circuit arrangements for operating light sources in general, i.e. where the type of light source is not relevant
    • H05B47/10—Controlling the light source
    • H05B47/175—Controlling the light source by remote control
    • H05B47/19—Controlling the light source by remote control via wireless transmission
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B2203/00—Indexing scheme relating to line transmission systems
    • H04B2203/54—Aspects of powerline communications not already covered by H04B3/54 and its subgroups
    • H04B2203/5429—Applications for powerline communications
    • H04B2203/5458—Monitor sensor; Alarm systems
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
    • Y02B20/40—Control techniques providing energy savings, e.g. smart controller or presence detection

Definitions

  • An aspect of the invention relates to a system that comprises a plurality of radar units.
  • the system may be used to control, for example, street lighting.
  • Other aspects of the invention relate to a method of configuring a system comprising a plurality of radar units, and a computer program product that enables a processor to carry out such a method.
  • a radar unit can detect movement in the following manner.
  • the radar unit radiates a transmission signal at a given frequency.
  • An object that is sufficiently close to the radar unit causes a reflection of the transmission signal, which the radar unit can receive.
  • the reflection will have a frequency that is different from that of the transmission signal.
  • the radar unit can detect the frequency difference and can thus detect the fact that the object moves and, in addition, at which speed the object moves.
  • the radar unit may initiate a control action on the basis of this detection. For example, in a speed control application, the radar unit may trigger a camera to take a picture of a speeding vehicle.
  • UK patent application published under number GB 2 444 734 describes a street lighting system that provides predictive illumination for objects passing along a roadway.
  • the presence of objects is detected by one or more sensors, which may be in the form of motion detection radars.
  • a potential risk that the transmission signal of a radar unit causes a detection error in another radar unit there is a potential risk that the transmission signal of a radar unit causes a detection error in another radar unit.
  • This potential risk exists in case respective radar units have respective frequency determining circuit that have nominally been set to transmit at an identical frequency. Slight frequency differences will typically occur due to tolerances of elements in the frequency determining circuits. There may be a frequency difference between two neighboring radar units, which is comparable with that produced by a moving object. A radar unit may mistakenly detect the transmission signal of another radar unit as being the reflection of a moving object.
  • the aforementioned potential risk is exacerbated by the following facts. Let it be assumed that an object is at a given distance from a radar unit and that another radar unit is at a given distance from the radar unit.
  • the radar unit will receive a reflection of its transmission signal with a magnitude that decreases with the distance of the object according to a power of four.
  • the radar unit will receive a transmission signal from the other radar unit with a magnitude that decreases with the distance of the other radar unit according to a power of two.
  • the transmission signal from the other radar unit may thus cause relatively strong interference. This particularly applies in a system where respective radar units should detect movement in respective detection areas that are relatively close to each other, or that may even need to overlap.
  • a system for controlling street lighting is an example.
  • Frequency synchronization can eliminate any frequency differences that may otherwise exist and that may give rise to erroneous detection.
  • frequency synchronization which causes all radar units to transmit at an identical frequency, leaves a related problem unresolved.
  • a transmission signal typically has noisy side bands, which are mainly due to oscillator phase noise.
  • the noisy side bands from a radar unit may constitute relatively strong wideband interference at another radar unit, which can effectively mask a reflection.
  • the radar units, which transmit at an identical frequency may desensitize each other. This can prevent detection of a moving object, which is in a desired detection area, but which is relatively far from any of the radar units.
  • a system comprises respective radar units having respective frequency determining circuits. At least a part of the respective frequency determining circuits have been set differently so as to cause neighboring radar units to transmit at respective different frequencies.
  • Another aspect of the invention relates to a method of configuring a system that comprises respective radar units having respective frequency determining circuits. In accordance with the invention, at least a part of the respective frequency determining circuits are set differently so as to cause neighboring radar units to transmit at respective different frequencies, at least nominally.
  • the different setting of the respective frequency determining circuits allows preventing that the transmission signal of a radar unit causes significant interference at another, neighboring radar unit. Erroneous detection due to such interference can thus be prevented.
  • the different frequency setting allows preventing noisy side bands from causing desensitization. A radar unit may thus detect a moving object that is relatively far, while being located relatively close to another radar unit.
  • An implementation of the invention advantageously comprises one or more of the following additional features, which are described in separate paragraphs. These additional features each contribute to achieving reliable operation.
  • the system advantageously comprises a system synchronization arrangement adapted to apply a system reference frequency to the respective radar units.
  • the respective frequency determining circuits comprise respective frequency synchronization circuits that define the respective different frequencies at which the respective radar units transmit by means of respective different frequency ratios with respect to the system reference frequency.
  • the system advantageously comprises a system controller arranged to assign the respective different frequency ratios to the respective frequency determining circuits of the respective radar units.
  • the respective different frequency ratios may be stored in respective memories comprised in the respective radar units.
  • the respective different frequency ratios may be a function of respective identification numbers of the respective radar units.
  • the system reference frequency may be a power supply frequency.
  • the respective radar units may be adapted to detect movement on the basis of a frequency difference between a transmitted signal and a received reflection of the transmitted signal.
  • a radar unit which can be used in a system according to the invention, and which is adapted to transmit at a transmission frequency, preferably comprises an
  • the interference resolution module adapted to detect whether a transmission frequency of another radar unit is within a detection frequency range around the transmission frequency of the radar unit itself. If so, the interference resolution module causes a shift of the transmission frequency of at least one of the following radar units: the radar unit itself and the other radar unit.
  • the radar unit preferably comprises a frequency determining circuit that has been preset so that the transmission frequency of the radar unit is nominally different from transmission frequencies of other radar units.
  • the radar unit preferably comprises a communication module adapted to establish a data communication with at least one of the following entities: other radar units and a system controller.
  • the interference resolution module is preferably adapted to cause the communication module to send a frequency shift request following a detection that a transmission frequency of another unit is within the detection frequency range, and to cause the shift of the transmission frequency only upon reception of a definite acknowledgment of the frequency shift request.
  • the radar unit preferably comprises a frequency conversion module adapted to mix a reception signal with a carrier signal that has the transmission frequency of the radar unit itself so as to obtain an intermediate frequency signal having a frequency spectrum.
  • the interference resolution module is preferably adapted to detect a static peak in the frequency spectrum of the intermediate frequency signal.
  • Fig. 1 is a pictorial diagram that illustrates a street lighting system comprising a plurality of radar units.
  • Fig. 2 is a block diagram that illustrates a basic radar unit with various optional modules from which different implementations can be derived.
  • Fig. 3 is a flow chart diagram that illustrates a series of steps that a radar unit carries out.
  • Fig. 1 pictorially illustrates a street lighting system SLS.
  • the street lighting system SLS comprises respective lampposts LP1-LP4, which are provided with respective radar units RU1-RU4.
  • a radar unit is preferably integrated in a luminary unit of the lamppost, where the radar unit is relatively safe from aggressions, in particular vandalism.
  • the street lighting system SLS further comprises a system controller SCT and an electrical power source EPS, which are jointly coupled to a splitter-combiner SC.
  • a power distribution cable CB couples the respective lampposts LP1-LP4 with their respective radar units RU1- RU4 to the splitter-combiner SC.
  • the street lighting system SLS basically operates as follows.
  • the electrical power source EPS provides an electrical power signal PW, which passes the splitter- combiner SC.
  • the electrical power signal PW reaches the respective lampposts LP1-LP4 with their respective radar units RU1-RU4 via the power distribution cable CB.
  • the electrical power signal PW has a given frequency, which will be referred to as power supply frequency Fpw hereinafter.
  • the power supply frequency F PW may serve as a system reference frequency FSYS- This will be explained in greater detail hereinafter.
  • the system controller SCT can transmit data DT and receive data DT, which will be referred to as downlink data and uplink data, respectively, hereinafter.
  • the splitter- combiner SC superposes, as it were, the downlink data from the system controller SCT on the electrical power signal PW. Accordingly, the downlink data can reach the respective radar units RU1-RU4 via the power distribution cable CB. Conversely, a radar unit transmits uplink data by superposing this data on the electrical power supply signal.
  • the uplink data reaches the splitter-combiner SC via the power distribution cable CB.
  • the splitter-combiner SC extracts the uplink data so that the system controller SCT receives this data.
  • the respective radar units RU1-RU4 transmit at respective different frequencies F1-F4. That is, a radar unit preferably transmits a radar signal at a unique frequency. All other radar units transmit radar signals at other frequencies. In case an object is sufficiently close to a radar unit, the radar unit receives a reflection of the radar signal. The radar unit processes this reflection so as to detect movement of the object. More specifically, the radar unit can detect a speed at which the object moves. This will be described in greater detail hereinafter.
  • a radar unit which is associated with a lamppost, controls the lamppost depending on detection of a moving object. For example, the radar unit may switch on the lamppost in case the radar unit detects that an object is moving with a speed, which falls within a particular speed range. The radar unit may control another lamppost by transmitting a command to the other lamppost, either directly or indirectly via the system controller SCT.
  • Fig. 2 schematically illustrates a basic radar unit RU with various optional modules from which various different implementations can be derived.
  • the basic radar unit RU comprises the following basic modules: a phase lock loop PLL, a transmission amplifier TX, an antenna module AM, a reception amplifier RX, a mixer MIX, a reception filter FIL, an analog to digital converter ADC, a fast Fourier transform module FFT1 , a programmable processor PPR, and a memory MEM.
  • the phase lock loop PLL comprises a frequency controllable oscillator OSC, a frequency divider DIV, a phase detector PD, and a loop filter LPF.
  • the antenna module AM may comprise a single antenna, or a single group of antennas, which is used for transmission and reception. Alternatively, the antenna module AM may comprise a pair of antennas, or a pair of groups of antennas, one that is used for transmission, the other being used for reception.
  • the programmable processor PPR comprises a movement detection module MVD and an interference resolution module IXR.
  • the interference resolution module IXR is optional.
  • the two aforementioned modules may each be in the form of, for example, a set of instructions that has been loaded into an instruction execution device. In such a software- based implementation, the set of instructions defines operations that the module concerned carries out, which will be described hereinafter.
  • the memory MEM may optionally comprise a frequency division value DV and an identification data ID, which uniquely identifies the basic radar unit RU.
  • the basic radar unit RU comprises the following further optional modules: a frequency extractor XTR, a reference frequency generator RFG, a modulator MOD, an additional fast Fourier transform module FFT2, and a communication interface CIF.
  • the communication interface CIF may be coupled to the power distribution cable CB illustrated in Fig. 1 via a splitter-combiner SC, which can separate data from the power supply signal and superpose data on the power supply signal.
  • the frequency extractor XTR and the reference frequency generator RFG are optional in the sense that there is an option in selecting one of those two entities.
  • Each of the other optional modules can be left out in an implementation that is derived from the basic radar unit RU illustrated in Fig. 2.
  • the street lighting system SLS illustrated in Fig. 1 need not comprise the system controller SCT. This will be explained in greater detail hereinafter.
  • the basic radar unit RU basically operates as follows.
  • the frequency controllable oscillator OSC of the phase lock loop PLL provides a carrier signal CW.
  • the carrier signal CW has a frequency that is equal to a reference frequency FR multiplied by the frequency division value DV.
  • the phase detector PD of the phase lock loop PLL may receive the reference frequency FR either from the frequency extractor XTR or from the reference frequency generator RFG.
  • the frequency divider DIV of the phase lock loop PLL may receive the frequency division value DV either from the memory MEM of from the programmable processor PPR.
  • the transmission amplifier TX amplifies the carrier signal CW, which is transmitted by means of the antenna module AM. Accordingly, the basic radar unit RU radiates a transmission signal, which is an amplified version of the carrier signal CW. In case an object is sufficiently close to the radar unit, the antenna module AM receives a reflection of the transmission signal.
  • the reception amplifier RX provides a reception signal RF, which comprises this reflection, or rather an amplified version thereof. In case the object is moving with respect to the radar unit, the reflection will have a frequency that is shifted with respect to that of the carrier signal CW. That is, there will be a frequency difference between the transmission signal and the reflection thereof. This is known as Doppler Effect. The greater the speed of the object is with respect to the radar unit, the greater the frequency difference is.
  • the mixer MIX effectively multiplies the reception signal RF by the carrier signal CW. Accordingly, the mixer MIX provides an intermediate frequency signal IF, which is a frequency shifted version of the reception signal RF. In case there is a reflection, which is due to a moving object, the intermediate frequency signal IF will comprise a signal component having a frequency equal to the frequency difference between the transmission signal and the reflection.
  • the reception filter FIL which has a given frequency passband, filters the intermediate frequency signal IF.
  • the reception filter FIL provides a filtered intermediate frequency signal IFF, which comprises signal components of the intermediate frequency signal IF that fall within the given frequency passband. Signal components outside the frequency passband are attenuated to a relatively large extent.
  • the frequency passband of the reception filter FIL effectively defines a speed range of interest.
  • an object that reflects the transmission signal produces a signal component in the intermediate frequency signal IF.
  • the frequency of the signal component depends on the speed of the object: the higher speed is, the higher the frequency of the signal component is. In case the object is stationary, which means "zero" speed, the frequency is also zero, which means that the signal component is a direct current component.
  • Speed thus effectively translates into frequency.
  • the speed of the object is so that the signal component in the intermediate frequency signal IF falls within the passband of the reception filter FIL, the basic radar unit RU can detect that speed.
  • the reception filter FIL suppresses this signal component, which prevents the basic radar unit RU from detecting that speed.
  • the analog to digital converter ADC provides a digital representation IFD of the filtered intermediate frequency signal IFF. This digital representation will be referred to as digital intermediate frequency signal IFD hereinafter.
  • the digital intermediate frequency signal IFD is a stream of samples.
  • the fast Fourier transform module FFT1 provides a frequency domain representation IFSl of the digital intermediate frequency signal IFD.
  • This frequency domain representation will be referred to as intermediate frequency spectrum representation IFSl hereinafter.
  • the fast Fourier transform module FFT1 converts respective consecutive series of samples in the digital intermediate frequency signal IFD into a stream of momentary intermediate frequency spectrum representations. That is, a series of samples, which covers a particular time interval, translates into a momentary frequency spectrum representation, which applies to this particular time interval. A subsequent series of samples, which covers a subsequent time interval, translates into a subsequent momentary frequency spectrum, which applies to this subsequent time interval, and so on.
  • the additional fast Fourier transform module FFT2 may provide an additional frequency domain representation IFS2 of the digital intermediate frequency signal IFD in a manner as described hereinbefore.
  • the additional fast Fourier transform module FFT2 may differ from the fast Fourier transform module FFT1 in terms of conversion characteristics, which may result in different resolutions.
  • the conversion characteristics of the fast Fourier transform module FFT1 may be optimized with regard to the movement detection module MVD.
  • the conversion characteristics of the additional fast Fourier transform module FFT2 may be optimized with regard to the interference resolution module IXR.
  • the movement detection module MVD detects a peak that may be present in the intermediate frequency spectrum representation IFSl .
  • a moving object which has a particular speed, causes such a peak to occur.
  • the peak occurs at a frequency, which indicates the speed of the moving object.
  • the movement detection module MVD may disregard any peak that does not satisfy one or more detection criteria. For example, a detection criterion can be that the peak should be above a threshold level. Another detection criterion can be that the peak should be within a predefined frequency window.
  • the movement detection module MVD causes the programmable processor PPR to carry out at least one control action upon detection of a peak that satisfies the detection criteria, if any.
  • a control action may be, for example, switching on a lamppost that has been provided with the basic radar unit RU. Accordingly, the lamppost is switched on when the radar unit detects a moving object.
  • Another control action may be, for example, switching on a neighboring lamppost.
  • the programmable processor PPR may submit a command to the neighboring lamppost by means of the communication interface CIF.
  • the modulator MOD may modulate the carrier signal CW in frequency. In another implementation, the modulator MOD may modulate the carrier signal CW in amplitude so that the transmission signal comprises transmission pulses. A combination of frequency modulation and pulse amplitude modulation is also possible. Any such modulation of the carrier signal CW allows the basic radar unit RU to further detect a distance at which the object is located from the radar unit.
  • the movement detection module MVD can be adapted to determine the speed and the distance of an object.
  • the basic radar unit RU illustrated in Fig. 2 has a detection frequency range.
  • a signal component in the reception signal RF having a frequency that is within the detection frequency range may cause the movement detection module MVD to carry out a control action.
  • the detection frequency range is at least partially defined by the following two parameters: the frequency of the carrier signal CW and the passband of the reception filter FIL. More precisely, the detection frequency range is the passband of the reception filter FIL convoluted with the frequency of the carrier signal CW. This statement is correct in case there is no additional filtering after the reception filter FIL. In that case, the detection frequency range has a width that is substantially determined by the reception filter FIL. In case there is additional filtering with a passband narrower than that of the reception filter FIL, the width of the frequency detection range will be smaller and defined by this additional filtering.
  • the reception signal RF may comprise a signal component that is not a reflection of the transmission signal that the basic radar unit RU transmits.
  • the signal component constitutes an interference, which can cause false detection of a moving object. More specifically, the interference will cause a peak in the intermediate frequency spectrum representation IFS1.
  • the movement detection module MVD may detect this peak and mistakenly cause the programmable processor PPR to carry out a control action.
  • the transmission signal of one radar unit constitutes interference for another radar unit. This is thanks to the fact that the respective radar units RU1-RU4 transmit at respective different frequencies F1-F4.
  • the frequencies preferably differ to such an extent that any given radar unit transmits at a frequency that is outside the detection frequency range of any other radar unit in the street lighting system SLS.
  • the respective radar units RU1-RU4 are frequency synchronized with each other. More specifically, in a radar unit, the carrier signal CW is frequency synchronized with the system reference frequency F SYS - It has been mentioned hereinbefore that the power supply frequency F PW may constitute the system reference frequency F SYS - The frequency extractor XTR illustrated in Fig. 2 may then extract the reference frequency FR from the electrical power signal PW.
  • the reference frequency FR which the frequency extractor XTR applies to the phase lock loop PLL, is the power supply frequency F PW , or a harmonic thereof.
  • the respective radar units RU1- RU4 have respective different frequency division values, which are predefined and can remain fixed.
  • the frequency division value DV can be stored in the memory MEM illustrated in Fig. 2, which may be of the read-only type.
  • the respective different frequency division values are preferably predefined so that the frequency of a carrier signal CW of a radar unit is outside the detection frequency range of any other radar unit in the street lighting system SLS.
  • the detection frequency range is a frequency band of 200 Hz centered on the frequency of the carrier signal CW; the detection frequency range extends from 100 Hz below the frequency of the carrier signal CW to 100 Hz above the frequency of the carrier signal CW.
  • the programmable processor PPR does therefore not need to comprise the interference resolution module IXR.
  • the respective different frequency division values may be preprogrammed in the respective radar units RU1-RU4. This preprogramming can take place in, for example, a factory, a retailer center, or on site by a technician who implements the street lighting system SLS.
  • the system controller SCT illustrated in Fig. 1 may assign the respective different frequency division values to the respective radar units RU1-RU4.
  • the system controller SCT may do so in a configuration phase that precedes an operational phase.
  • the system controller SCT may identify the respective radar units RU1-RU4 that form part of the system in a reconnaissance phase that precedes the configuration phase.
  • the system controller SCT may obtain one or more functional parameters of a radar unit, such as, for example, a detection frequency range.
  • a functional parameter can assist the system controller SCT in appropriately determining and assigning the respective frequency division values.
  • the respective radar units RU1-RU4 may autonomously determine the respective frequency division values on an ad- hoc basis. To that end, the respective radar units RU1-RU4 may apply a particular protocol according to which a particular radar unit reserves a frequency division value DV in coordination with the other radar units. This third implementation need not require the system controller SCT for that purpose.
  • the frequency division value DV can be a function of the identification data ID, which is stored in the memory MEM as illustrated in Fig. 2.
  • the identification data ID uniquely identifies a radar unit. Consequently, the frequency division value DV will be unique to the radar unit, assuming that the function is bijective or injective.
  • the programmable processor PPR of the radar unit may calculate the frequency division value DV on the basis of the identification data ID according to an appropriate function, which may be programmed in the programmable processor PPR.
  • the function preferably ensures that the frequency of a carrier signal CW of a radar unit is outside the detection frequency range of any other radar unit in the street lighting system SLS.
  • the system controller SCT illustrated in Fig. 1 may calculate the respective frequency division values on the basis of the respective identification data ID.
  • the respective radar units RU1- RU4 are free running in with respect to each other in terms of frequency.
  • a radar unit comprises the reference frequency generator RFG from which the phase lock loop PLL receives the reference frequency FR. It further implies that the reference frequency generator RFG is free running.
  • the reference frequency FR is locally determined by a resonance circuit, which forms part of the reference frequency generator RFG.
  • the resonance circuit may be in the form of, for example, a frequency crystal.
  • a radar unit may transmit at a frequency that is within the detection frequency range of another radar unit. This potential risk exists even if respective different frequency division values are initially assigned to the respective radar units RU1- RU4, which is a preferred option. Tolerances of elements in the reference frequency generator RFG, in particular the resonance circuit, may cause differences between reference frequencies, which can effectively compensate for the differences in frequency division values.
  • interference between radar units is prevented by means of the frequency adjustment procedure.
  • a radar unit can adjust its frequency division value DV, and can thus adjust the frequency of its carrier signal CW.
  • the frequency adjustment procedure involves the interference resolution module IXR illustrated in Fig. 2.
  • the interference resolution module IXR can initiate a frequency adjustment in case interference has been detected.
  • Fig. 3 illustrates a series of steps ST1-ST5 that the interference resolution module IXR may carry out as an example of implementation.
  • the street lighting system SLS indeed comprises the system controller SCT illustrated in Fig. 1.
  • the system controller SCT may be left out.
  • the additional fast Fourier transform module FFT2 illustrated in Fig. 2 is not present.
  • the interference resolution module IXR receives the intermediate frequency spectrum representation IFS1 from the fast Fourier transform module FFT1.
  • the interference resolution module IXR receives a current momentary intermediate frequency spectrum representation IFS I K from the fast Fourier transform module FFT1.
  • the interference resolution module IXR may effectively ignore peaks that are outside a specific level range, or peaks that are outside one or more specific frequency ranges, or both. All other peaks, which meet the detection criteria, are considered as relevant.
  • the interference resolution module IXR determines one or more characteristics of a relevant peak. These characteristics typically include a frequency at which the peak occurs and a level which the peak has.
  • the interference resolution module IXR stores respective characteristics of respective peaks, if any, as peak detection data in a buffer (PKD K ⁇ BUF). This buffer may form part of the memory MEM illustrated in Fig. 1.
  • the interference resolution module IXR compares the peak detection data of the L+1 most recent momentary intermediate frequency spectrum representations, L being an integer number. More specifically, the interference resolution module IXR determines whether there is a static peak in these most recent momentary intermediate frequency spectrum representations, or not ( ⁇ PKDKPKDK-L ⁇ ⁇ ?). In case each of these representations comprises a peak within a relatively narrow frequency window and within a relatively narrow level window, there is a static peak. Stated otherwise, there is a static peak in case a peak in any one of the L+1 most recent momentary intermediate frequency spectrum representations has substantially identical counterparts in the other L momentary intermediate frequency spectrum representations.
  • a static peak is typically caused by a transmission signal from another, neighboring radar unit.
  • the interference resolution module IXR carries out a frequency shift request submission step ST3.
  • the interference resolution module IXR awaits a subsequent momentary intermediate frequency spectrum representation that the fast Fourier transform module FFT1 will provide and carries out the peak detection step ST1 anew.
  • the interference resolution module IXR causes the radar unit to submit a frequency shift request to the system controller SCT (FSRQ ⁇ SCT).
  • the interference resolution module IXR further preferably prevents the radar unit from shifting frequency (INH FS).
  • the frequency division value DV remains fixed until further notice. This is part of a solution to prevent that two or more radar units simultaneously shift frequency, which could delay or even prevent interference from being resolved.
  • the interference resolution module IXR checks whether the following condition is true or false: the radar unit has received a frequency shift acknowledgment from the system controller SCT (SCT ⁇ ACK_ FSRQ ?). In case the aforementioned condition is true (Y), the interference resolution module IXR carries out a frequency shift step ST5. In case the aforementioned condition is false (N), the interference resolution module IXR remains in the acknowledgment awaiting step ST4.
  • the interference resolution module IXR causes the radar unit to shift frequency by changing the frequency division value DV (FS: ADV).
  • a frequency shift occurs in the carrier signal CW that the phase lock loop PLL provides.
  • the frequency shift is preferably so that the static peak that has been detected moves outside the detection frequency range of the radar unit.
  • the frequency division value DV is increased or decreased by a number of units that depends on several parameters. These parameters include the width of the detection frequency range and the reference frequency FR.
  • a basic approach is to change the frequency division value DV by a number of units at least equal to the width of the detection frequency range divided by the reference frequency FR.
  • the frequency shift will then at least be equal to the width of the detection frequency range, which ensures that the static peak moves outside the detection frequency range.
  • a more sophisticated approach can take into account the frequency at which the static peak occurs in order to determine the frequency shift that moves the stationary peak outside the detection frequency range.
  • the mixer MIX and the reception filter FIL are of the quadrature type, a distinction between positive and negative frequencies can be made.
  • a smallest possible change in the frequency division value DV can be determined, which will have a given sign, in order to achieve that the static peak moves outside the detection frequency range. That is, a relatively small increase or decrease in the frequency division value DV can be determined in order to achieve the aforementioned.
  • the interference resolution module IXR causes the radar unit to send a frequency shift confirmation to the system controller SCT (CNF ⁇ SCT).
  • the interference resolution module IXR may then proceed by carrying out the peak detection step ST1 anew. In case interference has been resolved, there will be no longer a static peak.
  • the system controller SCT also carries out a series of steps that relate to the frequency adjustment procedure. Basically, the system controller SCT preferably ensures that only one radar unit is shifting frequency at a time. Moreover, the system controller SCT preferably ensures that there are sufficient long pauses, as it were, between two successive frequency shifts. In case a radar unit has shifted frequency, a new situation occurs in terms of interference. The respective radar units RU1-RU4 should have sufficient time to evaluate this new situation in order to determine whether there is any interference, or not.
  • the system controller SCT may check whether one or more other frequency shift requests are pending.
  • a frequency shift request which a radar unit has submitted, is pending until the system controller SCT has received a frequency shift acknowledgment from the same radar unit.
  • the system controller SCT puts the frequency shift request that has been received in a queue.
  • the system controller SCT may manage the queue, for example, on a first-in first-out basis.
  • the system controller SCT may remove the frequency shift request that the radar unit has submitted from the queue.
  • Other frequency shift requests which remain in the queue, move one position up.
  • the system controller SCT may then send a frequency shift acknowledgment to the radar unit that has submitted the frequency shift request that has the highest position in the queue.
  • the system controller SCT may apply an appropriate delay before sending the frequency shift acknowledgment.
  • the radar units may autonomously carry out a frequency shift procedure.
  • the radar units may do so according to a coordination protocol that prevents radar units from simultaneously shifting frequency.
  • the radar units may communicate with each other in accordance with a Media Access Control (MAC) protocol.
  • MAC Media Access Control
  • a radar unit may broadcast a frequency shift request to the other radar units that form part of a same system.
  • a radar unit keeps track of frequency shift requests that have been broadcasted and maintains a list of pending requests. These lists can be managed in a joint fashion according to a predefined scheme.
  • the invention may be applied to advantage in numerous types of products or methods involving radar detection. Street lighting is merely an example. As another example, the invention may be applied to advantage in a radar-based surveillance system. Furthermore, it should be noted that the invention may be applied to advantage for various types of radar detection. Radar detection based on transmission of electromagnetic waves is merely an example. As another example, radar detection may be based on transmission of ultrasound waves. Moreover, radar detection need not necessarily be of the Doppler type. The invention may be applied to advantage in a system with radar units that detect the mere presence of objects.
  • a system need not necessarily comprise an electrical power source and a power distribution cable in order to implement the invention.
  • each radar unit may be powered individually by means of, for example, a solar panel, which may be complemented with a battery.
  • the radar units may communicate with each other in a wireless fashion.
  • the radar units may receive a system reference frequency in a wireless fashion too.
  • a system may be provided with a transmitter that broadcasts, as it were, the system reference frequency.
  • the system reference frequency may also be obtained from a transmitter that is external to the system.
  • a frequency determining circuit comprises a free running oscillator, which does need not form part of a
  • the free running oscillator comprises a resonance circuit, which determines the frequency at which the radar unit transmits.
  • the resonance circuit of a radar unit can be detuned with respect to that of a neighboring radar unit.
  • the resonant circuit may comprise, for example, an electrically controllable capacitance.
  • a radar unit can detect whether a transmission frequency of another radar unit is within a detection frequency range around a transmission frequency of the radar unit itself. For example, this detection can be done by means of a frequency counter.
  • a frequency counter may count zero crossings in the filtered intermediate frequency signal IFF.
  • the frequency counter will provide respective frequency count values for respective consecutive time intervals.
  • the respective frequency count values will be relatively similar. Namely, the respective frequency count values will indicate a frequency of a static peak in the intermediate frequency spectrum representation IFS1.
  • the fast Fourier transfer modules FFT1 and FFT2 may each be replaced by a filter bank comprising respective different filters with respective detectors, which may apply respective different thresholds.
  • the radar unit may request one or more neighboring radar unit to change their transmission frequencies rather than changing its own transmission frequency. This request can be handled by a system controller. Alternatively, the radar unit can broadcast the request to the neighboring radar units, which handle the request according to a predefined appropriate protocol. As another example, the frequency adjustment procedure may be uncoordinated in the sense that each radar unit may
  • interference resolution may take longer in such an implementation, or may even not be achieved in an extreme case.
  • radar unit should be understood in a broad sense. The term embraces any entity capable of transmitting a signal and deriving information from a received reflection of the signal.
  • frequency synchronization circuit should be understood in a broad sense.
  • the term embraces any entity capable of achieving and maintaining a specific frequency ratio between two signals.
  • the term thus embraces, for example, phase lock loops and frequency- lock loops.
  • a single module may carry out several functions, or several modules may jointly carry out a single function.
  • the drawings are very diagrammatic.
  • the fast Fourier transform module FFT1 and the programmable processor PPR may form part of a single processor module.

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  • Engineering & Computer Science (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Remote Sensing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Power Engineering (AREA)
  • Signal Processing (AREA)
  • Radar Systems Or Details Thereof (AREA)

Abstract

La présente invention concerne un système (SLS) comportant des unités de radar respectives (RU1-RU4) ayant des circuits de détermination de fréquences respectives. Au moins certains des circuits de détermination de fréquences respectives ont été réglés différemment pour entraîner la transmission à des fréquences respectives différentes (F1-F4) par les unités de radar voisines.
PCT/IB2011/053553 2010-08-16 2011-08-09 Système de radars multiples WO2012023087A1 (fr)

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Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014097088A1 (fr) 2012-12-18 2014-06-26 Koninklijke Philips N.V. Commande d'émission d'impulsions provenant d'un capteur
EP2651194A3 (fr) * 2012-04-12 2015-06-24 Steinel GmbH Dispositif de détection extérieur et lampe extérieure commandée par un détecteur de mouvements
EP2782428A3 (fr) * 2013-03-22 2015-12-23 RP-Technik GmbH Installation d'éclairage de secours dotée d'une fonction d'interface vers des systèmes de gestion technique de bâtiment et procédé de communication associé
CN105182294A (zh) * 2015-09-15 2015-12-23 浙江嘉乐智能技术有限公司 一种基于无线控制的雷达设备调节装置及方法
EP3572829A1 (fr) * 2018-05-25 2019-11-27 Airbus Defence and Space GmbH Réseaux radar synchronisés
WO2020035314A1 (fr) * 2018-08-14 2020-02-20 Signify Holding B.V. Dispositif de capteur de micro-ondes, et procédés de détection, et système d'éclairage utilisant le dispositif de capteur
CN112534296A (zh) * 2018-08-14 2021-03-19 昕诺飞控股有限公司 微波传感器设备以及使用传感器设备的传感方法和照明系统
EP3842822A3 (fr) * 2015-04-20 2021-09-08 ResMed Sensor Technologies Limited Détection radiofréquence à plusieurs détecteurs
US20220057503A1 (en) * 2019-01-09 2022-02-24 Signify Holding B.V. Systems, methods, and devices for drone detection using an outdoor lighting network

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1901431A2 (fr) * 2006-09-12 2008-03-19 Fujitsu Ltd. Oscillateur à verrouillage de phase et système à radars multiples l'utilisant
GB2444734A (en) 2006-12-11 2008-06-18 Andrew Robert Linton Howe Energy efficient road lighting employing presence detection
DE202009010496U1 (de) * 2008-08-01 2009-12-17 Steinel Gmbh Sensorvorrichtung
US20090309785A1 (en) * 2006-07-13 2009-12-17 Siemens Aktiengesellschaft Radar arrangement

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090309785A1 (en) * 2006-07-13 2009-12-17 Siemens Aktiengesellschaft Radar arrangement
EP1901431A2 (fr) * 2006-09-12 2008-03-19 Fujitsu Ltd. Oscillateur à verrouillage de phase et système à radars multiples l'utilisant
GB2444734A (en) 2006-12-11 2008-06-18 Andrew Robert Linton Howe Energy efficient road lighting employing presence detection
DE202009010496U1 (de) * 2008-08-01 2009-12-17 Steinel Gmbh Sensorvorrichtung

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2651194A3 (fr) * 2012-04-12 2015-06-24 Steinel GmbH Dispositif de détection extérieur et lampe extérieure commandée par un détecteur de mouvements
US9766327B2 (en) 2012-12-18 2017-09-19 Philips Lighting Holding B.V. Controlling transmission of pulses from a sensor
US10444334B2 (en) 2012-12-18 2019-10-15 Signify Holding B.V. Controlling transmission of pulses from a sensor
WO2014097088A1 (fr) 2012-12-18 2014-06-26 Koninklijke Philips N.V. Commande d'émission d'impulsions provenant d'un capteur
EP2782428A3 (fr) * 2013-03-22 2015-12-23 RP-Technik GmbH Installation d'éclairage de secours dotée d'une fonction d'interface vers des systèmes de gestion technique de bâtiment et procédé de communication associé
US11559217B2 (en) 2015-04-20 2023-01-24 Resmed Sensor Technologies Limited Multi sensor radio frequency detection
EP3842822A3 (fr) * 2015-04-20 2021-09-08 ResMed Sensor Technologies Limited Détection radiofréquence à plusieurs détecteurs
US11857300B2 (en) 2015-04-20 2024-01-02 Resmed Sensor Technologies Limited Multi sensor radio frequency detection
CN105182294A (zh) * 2015-09-15 2015-12-23 浙江嘉乐智能技术有限公司 一种基于无线控制的雷达设备调节装置及方法
EP3572829A1 (fr) * 2018-05-25 2019-11-27 Airbus Defence and Space GmbH Réseaux radar synchronisés
WO2019224251A1 (fr) * 2018-05-25 2019-11-28 Airbus Defence and Space GmbH Réseaux radar synchronisés
US11947030B2 (en) 2018-05-25 2024-04-02 Airbus Defence and Space GmbH Synchronized radar networks
WO2020035314A1 (fr) * 2018-08-14 2020-02-20 Signify Holding B.V. Dispositif de capteur de micro-ondes, et procédés de détection, et système d'éclairage utilisant le dispositif de capteur
US11172561B2 (en) 2018-08-14 2021-11-09 Signify Holding B.V. Microwave sensor device, and sensing methods, and lighting system using the sensor device
CN112534296A (zh) * 2018-08-14 2021-03-19 昕诺飞控股有限公司 微波传感器设备以及使用传感器设备的传感方法和照明系统
US20220057503A1 (en) * 2019-01-09 2022-02-24 Signify Holding B.V. Systems, methods, and devices for drone detection using an outdoor lighting network
US11914024B2 (en) * 2019-01-09 2024-02-27 Signify Holding B.V. Systems, methods, and devices for drone detection using an outdoor lighting network

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