JP2001134850A - Invasion detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an invasion detector improved in reliability in the detection of invasion into a car. SOLUTION: Concerning the invasion detector for irradiating the inside of a car with the signal of a specified frequency and detecting the invasion of a person into the car on the basis of a signal receiving a reflected wave from the inside of the car, this device is provided with a judging means for judging the invasion of a person into the car when the level of the receiving signal exceeds any one of or both a threshold value Va provided on the plus side of a reference value Vs and a threshold value Vb provided on the minus side of the reference value Vs.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improving the reliability of an intrusion detection device for detecting the intrusion of a person into a vehicle interior.

[0002]

2. Description of the Related Art There is an intrusion detection device which radiates a radio wave of a specific frequency into a vehicle interior and detects whether or not the vehicle enters the vehicle interior based on the reflected wave. For example, considering the intruder as a moving object, a detection signal Vd consisting of a frequency of a difference between the irradiation wave and the reflected wave is compared with a threshold value Va provided on the plus side of the reference value Vs, and the detection signal Vd is set to the threshold value. If it is larger than the value Va, it is determined that there is an intruder, and an intrusion detection signal is output to the alarm control unit.

[0003]

However, in such a conventional intrusion detection device, the detection signal Vd always exceeds the reference value Vs depending on the direction and speed of the intruder's movement, or the angle of radio wave irradiation at the intruder. It is not always symmetrical about the center. For this reason, when the detection signal Vd is compared with a threshold value Va provided on the plus side of the reference value Vs to determine the intrusion, the detection signal Vd has a small wave height on the plus side and a large wave height on the minus side. Has the problem that it cannot detect intrusions. Further, the reference value Vs is usually set by dividing a predetermined DC voltage by resistance division or the like. However, the resistor has a temperature characteristic, and when the temperature changes, the reference value Vs also fluctuates, and the reliability of the intrusion detection determination decreases. There is a problem.

When the detection signal Vd has a threshold value V
Even if it is detected that it is larger than a, it may not always be intruded due to noise, abnormality of the control circuit, or the like.

An object of the present invention is to solve the above-described problem and to provide an intrusion detection device which has improved reliability in detecting intrusion into a vehicle interior by a detection environment.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method of irradiating a signal of a specific frequency into a vehicle interior and receiving a signal reflected from the vehicle interior into a vehicle interior based on a received signal. In the intrusion detection device for detecting intrusion of a person, one of a threshold value Va provided on the plus side of the reference value Vs and a threshold value Vb provided on a minus side of the reference value Vs. Or when both of them are exceeded, a determination means is provided for determining that a person has entered the vehicle interior.

[0007] Further, there is provided a detecting means for detecting an amplitude center level of the received signal, and the amplitude center level detected by the detecting means is set as the reference value Vs.

The determining means does not determine that a person has entered when the time during which the level of the received signal continuously exceeds the threshold value Va or the threshold value Vb is shorter than a predetermined time T1. It is characterized by the following.

Further, the determining means stops the determining operation when the time during which the level of the received signal continuously exceeds the threshold value Va or the threshold value Vb is longer than a predetermined time T2. It is assumed that.

[0010] Further, there is provided a power cutoff means for cutting off an output of a high frequency power supply section for oscillating the signal of the specific frequency when the judgment means stops the judgment operation.

Further, when the determining means stops the determining operation, it outputs an abnormality notification signal for notifying that it is abnormal.

[0012] Preferably, the apparatus further comprises temperature detecting means for detecting a temperature near the irradiation source of the signal of the specific frequency, and temperature correcting means for correcting the level of the received signal based on the detection result of the temperature detecting means. It is a feature.

In addition, the power supply apparatus further includes voltage detecting means for detecting a power supply voltage TB supplied to a high-frequency power supply unit for oscillating the signal of the specific frequency.
When it is detected that B has dropped below a predetermined value, the determination operation is stopped.

If the determination means detects that the level of the received signal exceeds the threshold value Va or the threshold value Vb within a predetermined time T0 after the start of the intrusion detection operation, The power supply device further includes a power supply cutoff unit that cuts off an output of a high frequency power supply unit for oscillating a frequency signal.

[0015] Preferably, the apparatus further comprises a power cutoff means for cutting off an output of a high frequency power supply section for oscillating the signal of the specific frequency when the judgment means detects that the inside of the intrusion detection device is abnormal. It is a feature.

[0016]

FIG. 1 is a block diagram showing the configuration of an intrusion detection device according to an embodiment of the present invention. Less than,
This will be described with reference to the drawings.

Reference numeral 1 denotes a security controller 2 for detecting the intrusion of a person into the vehicle compartment and performing security control of the entire vehicle.
A sensor unit that outputs an intrusion detection signal, an abnormality detection signal, and the like, oscillates a high frequency of a predetermined frequency f1 and supplies the transmission unit 12 with an oscillating unit 11, which radiates radio waves to a predetermined range in the vehicle compartment. A transmitting unit 12, a receiving unit 13 configured by an antenna and the like for receiving a reflected radio wave (reflected wave) from an object in the vehicle cabin, a reflected wave (frequency f2) received by the receiving unit 13 and an oscillated wave ( A mixing unit 14 that mixes the frequencies f1) to generate Doppler waves (difference frequencies f1 to f2) based on a moving object in the vehicle cabin, and an amplification unit 1 that amplifies a detection signal from the mixing unit 14 and outputs the amplified signal to the microcomputer 16
5. A / D conversion of the input signal from the amplifier 15 and comparison with predetermined threshold values Va and Vb, or comparison of the pulse width of a signal (L level) based on the comparison result with predetermined times T1 and T2 The microcomputer 16 outputs the result to the security controller unit 2 (microcomputer 21) via the output unit 17 and determines the result of intrusion detection, abnormality detection, and the like, and outputs the determination result of the microcomputer 16 to the microcomputer 21 on the security controller unit 2 side. Output section 17, battery power supply T
High frequency (for example, 2.45 GHz) based on B (12 V)
And a power supply unit 19 for supplying a necessary voltage to each circuit (each unit) of the sensor unit 1.

Reference numeral 2 denotes a security controller unit which collectively performs security control such as abnormality detection of the entire vehicle. In this embodiment, a part related to the sensor unit 1 includes a power supply unit 22 for driving the security controller unit, The microcomputer 21 is configured to control an alarm device and the like by comprehensively determining a detection (intrusion, abnormal) signal from the sensor unit 1 and a detection result from another sensor. The microcomputer 16 and the microcomputer 21 are connected via an interface (not shown).

FIG. 2 is a flowchart of the detection process performed by the microcomputer 16. 3A and 3B are explanatory diagrams for explaining the principle of intrusion detection. FIG. 3A is a diagram showing a detection signal waveform, FIG. 3B is a diagram showing detection timing in the microcomputer, and FIG. 3C is a diagram showing an intrusion detection signal. . FIG. 4 is a temperature correction coefficient map. This processing is performed by the high-frequency power supply unit 18 of the sensor unit 1 of the apparatus.
Start from the point when is turned on. In addition, the high frequency power supply unit 1
Reference numeral 8 is turned on in conjunction with a door lock operation by a remote control key of the vehicle.

In step S1, it is determined whether or not the power supply voltage TB is higher than the predetermined voltage V0. If the power supply voltage TB is higher than the predetermined voltage V0, the process proceeds to step S2. If the power supply voltage TB is lower than the predetermined voltage V0, the process is terminated. That is, the power supply voltage (normally, 12 V from the battery) necessary for the oscillation unit 11 to maintain stable oscillation is detected. This determination is made on both the sensor unit 1 side and the security controller unit 2 side to confirm whether there is any abnormality.

In step S2, it is determined whether or not the control circuit of the entire intrusion detection device including the sensor unit 1 and the security controller unit 2 has an abnormality. If there is an abnormality in the control circuit, the process is terminated. Step S if there is no abnormality
Move to 3. This judgment is for judging whether or not the judgment results of the microcomputer 16 and the microcomputer 21 are coincident with each other, based on the coincidence and non-coincidence of the detection result of the power supply voltage TB and the detection results of various diacs.

In step S3, the temperature near the oscillating unit 11 is detected by a temperature sensor or the like provided on the same substrate as the oscillating unit 11 (not shown), and the process proceeds to step S4. The high-frequency oscillation output has a temperature dependency, and the output tends to decrease as the temperature increases. Therefore, the intensity of the reflected wave also changes in accordance with the intensity of the radiated radio wave due to the temperature. Therefore, it is necessary to correct the received signal according to the intensity of the irradiated radio wave.

In step S4, a received signal is detected, and the flow advances to step S5. That is, the reflected wave from the cabin is received by the receiving unit 13 and mixed by the mixing unit 14 with the oscillated wave of the oscillating unit 11. In this mixing, when an object (for example, an intruder) moving in the vehicle compartment is irradiated with a radio wave of frequency f1, the frequency f2 of the reflected wave changes due to the Doppler effect according to the movement of the object. As shown in FIG. 3A, by using the output level at the difference frequency (1 to 100 Hz at f1 to f2) as a detection signal, only a moving object (such as an intrusion operation) can be detected. Output of mixing section 14 (frequency f1 to f2
Is referred to as a detection signal before temperature correction) and is amplified by the amplifying unit 15 and output to the microcomputer 16. The microcomputer 16 performs A / D conversion and intrusion detection processing.

In step S5, the temperature is corrected, and the flow advances to step S6. That is, the fluctuation of the oscillation output that changes with temperature is corrected. The correction coefficient K for temperature correction is a map showing the relationship between the temperature and the correction coefficient K in FIG.
6 is stored in the memory. For example, if the oscillation output at 20 degrees Celsius is 1 (reference), then minus 2 degrees Celsius
At 0 degree, the oscillation output is increased, so the detection signal before temperature correction is multiplied by 0.8. Conversely, when the temperature is 50 degrees Celsius, the oscillation output is multiplied by 1.2, and when the temperature is 85 degrees Celsius, the oscillation output is further decreased, so that the value is multiplied by 1.4. In this way, the subsequent judgment is made based on the detection signal multiplied by the correction coefficient K (hereinafter, this signal is simply referred to as detection signal Vd).

In step S6, the comparison (level judgment) between the detection signal Vd and the threshold values Va and Vb is L.
(Low level). If it is L (low level), the process proceeds to step S7. If it is H (high level), the process returns to step S3. As shown in FIGS. 2A and 2B, the level comparison unit in the microcomputer 16 determines whether the detection signal Vd is equal to the reference value Vs.
L (low level) if the threshold value Va or the threshold value Vb provided on both sides of the threshold value Va is exceeded, and H (high level) if the detection signal Vd is between the threshold value Va and the threshold value VaVb. . The threshold value Va and the threshold value Vb are equal to the reference value V.
same as s (absolute value Va relative to reference value = absolute value V
In addition to b), it may be appropriately changed by an experiment or the like. Further, not only one of the threshold value Va and the threshold value Vb, but also L (low level) may be output only when the threshold value Va is exceeded and the threshold Vb is exceeded. Note that the detection signal Vd is set to a threshold value V
The comparison between both a and Vb is because the detection signal Vd is not vertically symmetrical with respect to the reference value Vs because, for example, the action of the intruder in the vehicle cabin is not symmetrical with respect to the irradiation direction of the irradiation radio wave.
This is to prevent the comparison result from being different. Also, the reference value V
Although s is a predetermined voltage set by resistance division, the resistor has temperature dependence and the reference value Vs itself fluctuates.
Therefore, for the detection signal Vd, a value passed through a low-pass filter that passes only a frequency sufficiently lower than the frequency (for example, 1 to 100 Hz) of the detection signal Vd,
That is, the center level of the detection signal Vd is set to the reference value Vs. By this processing, the DC fluctuation (shift) of the detection signal Vd is reduced, and the detection signal Vd is uniformly distributed vertically with respect to the reference value Vs. Note that this low-pass filter is not constituted by hardware, but is provided by the microcomputer 16 based on the detection signal Vd.
The filter processing is performed digitally within. Also,
A method of providing the threshold values Va and Vb on both sides of the reference value Vs and a method of setting the reference value Vs to a value obtained by performing a low-pass filter process on the detection signal Vd include an intrusion detection device using the Doppler effect as in the present embodiment. However, the present invention can be applied to other intrusion detection devices that use reflected waves, such as infrared rays and ultrasonic waves, as they are for intrusion detection determination.

In step S7, it is determined whether or not the time t maintaining L (low level) has exceeded a predetermined time T1, and if the time t has exceeded the predetermined time T1, the process proceeds to step S8, and if it has not exceeded the predetermined time T1. If so, the process returns to step S3. That is, it is determined whether or not L (low level) continues for T1 or more. The predetermined time T1 is for distinguishing the detection signal Vd from noise. For example, T1 is set to about 20 ms, and a peak of the detection signal Vd shorter than this time is determined to be noise.

In step S8, it is determined whether or not the time t maintaining L (low level) has exceeded a predetermined time T2. If the time t has exceeded the predetermined time T2, the process proceeds to step S12, and if the time t has not exceeded the predetermined time T2. If so, the process moves to step S9. That is, it is determined whether or not L (low level) continues for T2 or more. The predetermined time T2 is for distinguishing the detection signal Vd from the device abnormality. For example, T2 is set to about 10 s, and if it is longer than this time, it is determined that the device is abnormal. In the present embodiment, the intrusion of a person into the vehicle interior is detected by the Doppler effect of the irradiation wave and the reflected wave, and the detection signal Vd immediately after the invasion is large, and the detection signal Vd thereafter is normally the threshold value Va. And Vb), and it is determined that the L (low level) state continues for a predetermined time T2 or more is an abnormality on the device side.

In step S9, it is determined whether or not a predetermined time T0 has elapsed from the start of the intrusion detection processing to the detection of L (low level). If the predetermined time T0 has elapsed, the flow advances to step S10. The process proceeds to step S11 if the predetermined time T0 has not elapsed. The start of the intrusion detection process
For example, a door lock operation using a remote control key (sensor unit 1)
Is turned on in conjunction with the high-frequency power supply unit 18). This process is a process of determining whether or not an intrusion has been detected immediately after the start of the intrusion detection process, and is performed to prevent a determination of intrusion detection when a door is locked while leaving a child or a pet or the like.

In step S10, it is determined that there is an intruder in the vehicle compartment, and an intrusion detection signal is output to the microcomputer 21 of the security controller 2 via the output unit 17. The intrusion detection signal satisfies the above condition (that is, the detection level exceeds the thresholds Va and Vb, the period t during which the detection level exceeds the threshold Va is between T1 and T2, and the first pulse starts the intrusion detection processing. May be output each time the state exceeds the time T0), or may be output when a state satisfying the above condition is counted several times. The security controller unit 2 makes a final judgment on the presence or absence of an intruder, for example, based on a comprehensive judgment with the detection result of another intrusion detection device that detects intrusion such as a door opening detection device. As a result, if it is comprehensively determined that there is an intruder, the horn sounds, the headlights and the like blink. In addition, measures such as prohibiting the start of the engine are taken. In the present embodiment, the comprehensive judgment is made based on the intrusion detection signal from the sensor unit 1 and the intrusion detection signal from the other intrusion detection sensors in the security controller unit 2. Only the final one may be issued as an alarm.

In step S11, when the intrusion detection operation is started, it is determined that there is already a passenger in the vehicle compartment, the high-frequency power supply unit 18 is turned off, and the process is terminated. In other words, the detection of the intrusion before the predetermined time T0 (for example, 30 seconds) has elapsed since the start of the intrusion detection operation is based not on the intrusion from the outside but on the movement of the child or pet left in the vehicle. Therefore, the intrusion detection processing is stopped because the reliability of the present sensor is low. Then, the high-frequency power supply unit 18 is instructed to turn off the power, thereby saving power consumption.

In step S12, it is determined that the sensor is abnormal, and the high-frequency power supply 18 is turned off, and the process proceeds to step S13. That is, in the present embodiment, the intrusion of a person into the vehicle interior is detected by the Doppler effect of the irradiation wave and the reflected wave,
The movement of the person immediately after the invasion is the largest and therefore the detection signal is large, and the detection signal Vs thereafter is usually the threshold value (V
a, Vb), for example, T2 (5
It is determined that the L (low level) state continues for more than about 00 ms) is abnormal, and the intrusion detection processing is stopped. Then, the high-frequency power supply unit 18 is instructed to turn off the power, thereby saving power consumption.

In step S13, an abnormality detection signal is output to the microcomputer 21 of the security controller unit 2 via the output unit 17, and the process is terminated.

As described above, according to the present embodiment, the detection signal Vd for correcting the irradiation output of the radio wave depending on the temperature and judging the presence or absence of intrusion is compared with the threshold values Va and Vb provided on both sides of the reference value. By comparison, the detection signal Vd
And vertical asymmetries. Further, the detection signal Vd
Of the intrusion detection process by comparing the pulse width t during the period exceeding the threshold values Va and Vb with the predetermined times T1 and T2, and comparing the L output timing of the level determination signal with the time T0 from the start of detection. Reliability can be improved.

[0034]

As described above, according to the present invention, it is possible to provide an intrusion detection device with improved reliability in detecting intrusion into a vehicle interior by a detection environment.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an intrusion detection device according to an embodiment of the present invention.

FIG. 2 is a flowchart of an intrusion detection process performed by a microcomputer 16;

FIG. 3 is an explanatory diagram of the principle of intrusion detection.

FIG. 4 is a temperature correction coefficient map.

[Explanation of symbols]

1 ··· Sensor part 17 ··· Output part
11 ... oscillator, 18 ... high frequency power supply, 12 ... transmitter, 19 ... power supply, 13 ... receiver, 2 ... security controller, 14 ... mixing Department,
21: microcomputer, 15: amplifier,
22: power supply unit, 16: microcomputer.

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2G005 DA04 5C084 AA02 AA04 AA07 BB27 BB32 BB34 CC02 CC16 CC19 DD03 DD08 DD41 EE06 GG03 GG07 GG09 GG24 GG38 GG39 GG42 GG43 GG44 GG52 GG55 GG56 GG71 AC05 GG57 AC07 AH31 AK22

Claims (10)

[Claims] 1. An intrusion detection device that irradiates a signal of a specific frequency into a vehicle interior and detects intrusion of a person into the vehicle interior based on a reception signal that receives a reflected wave from the vehicle interior. When the level exceeds one or both of the threshold value Va provided on the plus side of the reference value Vs and the threshold value Vb provided on the minus side of the reference value Vs, a person enters the vehicle interior. An intrusion detection device comprising a determination means for determining that there has been an intrusion. 2. The intrusion detection device according to claim 1, further comprising a detection unit for detecting an amplitude center level of the received signal, wherein the amplitude center level detected by the detection unit is used as the reference value Vs. . 3. When the time during which the level of the received signal continuously exceeds the threshold value Va or the threshold value Vb is shorter than a predetermined time T1, the determining means does not determine that a person has entered. The intrusion detection device according to claim 1, wherein: 4. The determining means stops the determining operation when the time during which the level of the received signal continuously exceeds the threshold value Va or the threshold value Vb is longer than a predetermined time T2. The intrusion detection device according to claim 1, wherein 5. The power supply according to claim 4, further comprising: a power cutoff unit that cuts off an output of a high frequency power supply unit for oscillating the signal of the specific frequency when the determination unit stops the determination operation. Intrusion detection device. 6. The intrusion detection device according to claim 4, wherein when the judgment means stops the judgment operation, an abnormality notification signal for notifying that the operation is abnormal is output. 7. A temperature detecting means for detecting a temperature near an irradiation source of the signal of the specific frequency, and a temperature correcting means for correcting a level of a received signal based on a detection result of the temperature detecting means. The intrusion detection device according to claim 1, wherein: 8. A voltage detecting unit for detecting a power supply voltage TB supplied to a high-frequency power supply unit for oscillating the signal of the specific frequency, wherein the determining unit determines that the power supply voltage TB has dropped below a predetermined value. 2. The intrusion detection device according to claim 1, wherein when detecting the fact, the determination operation is stopped. 9. Within a predetermined time T0 after the determination means starts the intrusion detection operation, the level of the received signal is changed to the threshold value Va or the threshold value Vb.
2. The intrusion detection device according to claim 1, further comprising a power cutoff unit that cuts off an output of a high-frequency power supply unit for oscillating the signal of the specific frequency when it is detected that the signal exceeds a predetermined frequency. 10. A power supply shutoff means for shutting off an output of a high frequency power supply for oscillating the signal of the specific frequency when the judgment means detects that the inside of the intrusion detection device is abnormal. The intrusion detection device according to claim 1, wherein: