JP2008249338A - Data processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data processor capable of preventing malfunction, even when external noise level, having a steep rise with a fixed period, temporarily goes down. <P>SOLUTION: When the rise time of input waveform, having different period, is short, following five conditions are determined continuously: (1) 450 ms has not elapsed, after the output voltage of a sensor becomes 0.45 V or above, (2) number of the crests of input waveform is 7 or higher, (3) in a state that sensor signal is being generated, (4) maximum value of period difference for the past 7 crests is 10 ms or shorter, (5) peak generating time for the past 7 crests is 25 ms or shorter, and when five conditions are satisfied, the satisfaction is held for inhibiting the data processing, based on the sensor output. Meanwhile, when a rise time to the peak which is not observed for the external noise is generated, namely, when peak generating time for the past 7 crests is 25 ms or longer, the prohibition is canceled and the data processing is executed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a data processing apparatus that performs data processing such as waveform feature detection by A / D conversion output of an input signal, and more particularly to a data processing apparatus that can prevent malfunction due to noise.

There are many devices that perform some control based on a signal obtained from a certain sensor. For example, in a vehicle security system, unauthorized opening of a door, entry into a vehicle interior, vehicle vibration, When an illegal intrusion such as a broken glass is detected, an alarm is generated, or an intrusion sensor at a predetermined location is notified by radio. The presence or absence of unauthorized intrusion into the vehicle is detected by extracting the fluctuation of the waveform (see, for example, Patent Document 1).
JP 2004-142660 A

FIG. 1 is a block diagram showing the configuration of a general security system. The security ECU 31 has a keyless entry function for performing lock control, and performs vehicle door lock / unlock control, door open / close control, An alarm is issued when the vehicle interior is intruded by unauthorized means, and arming / disarming control, vehicle door lock / unlock control, etc. are performed in response to a request signal from the transmitter 32.
The transmitter 32 has a lock button L and an unlock button U. When the lock button L is pressed, security setting (arming) is performed, and when the unlock button U is pressed, security reset (disarming) is performed.

  The security ECU 31 includes a courtesy SW 33 for detecting the open / closed state of the door, a hood SW 34 for detecting the open / closed state of the hood, and an intrusion for detecting that the door has been opened or the vehicle has been intruded by other than a proper method. SW and sensor outputs such as a sensor 35, a vibration sensor 36 for detecting vehicle vibration, an IGSW 37 for detecting an on / off switching state of an ignition switch, and a lock position SW 38 for detecting door locking and unlocking are input. In addition, a lock motor 39 that drives a door lock mechanism that locks and unlocks the door, a horn 40 that performs an alarm operation at the time of alarm, a hazard lamp 41, and the like are connected.

FIG. 2 shows an example of the intrusion sensor 35, which is a block diagram showing the configuration of an intrusion sensor using millimeter wave band high frequency signals. The output of the oscillation circuit 51 that generates a high frequency signal of 4 MHz is shown in FIG. The multiplication / amplification circuit 52 multiplies and amplifies the signal to a frequency signal of 24 GHz and transmits the signal from the transmission antenna 53. Then, the reflected wave that is reflected when the transmission radio wave from the transmission antenna 53 hits a surrounding object is received by the reception antenna 54, and the reception signal from the reception antenna 54 and the transmission signal from the multiplication / amplification circuit 52 are combined by the mixing circuit 56. The signals are mixed and input to the detection circuit 57.
Then, the detection circuit 57 extracts the frequency component of the difference between the reception signal and the transmission signal as a beat signal, and the microcomputer 58 changes the waveform due to the movement of the object based on the data obtained by A / D converting the output of the detection circuit 57. The presence or absence of unauthorized intrusion into the vehicle is detected by extracting.

In the data processing device using a microcomputer that processes the input signal like the above intrusion sensor, the signal from the sensor is sampled by the A / D converter and digitized, and the data processing circuit is based on the digital signal. Judgment processing is performed.
In this case, if the sampling period is short, the A / D converted waveform is close to the original signal, but if the sampling period is long, the A / D converted waveform is far from the original signal. Therefore, when the maximum frequency included in the original signal is fp, the sampling frequency is usually set to 2 fp or more.

  In such a data processing apparatus, when a signal having a frequency higher than the frequency component necessary for the system is input to the sensor as external noise, the signal having a frequency component higher than the sampling frequency of the A / D converter has a waveform. Since it is not possible to recognize whether the noise is external noise or not, there is a possibility of malfunction, and therefore, when high-frequency noise enters, it is necessary to stop data processing.

  In addition, some data processing devices detect a signal with a substantially constant time interval even though the cycle is indefinite. When a power-on / off signal of a mobile phone as shown in FIG. 3 is input, since such a signal cannot be recognized well unless the sampling frequency of the A / D converter is increased, the data processing apparatus May malfunction.

  For this reason, conventionally, as shown in FIG. 4, (1) 450 ms has not elapsed since the output voltage of the sensor became 0.45 V or higher, (2) the maximum value of the period difference of each peak of the input waveform is 10 ms. (3) The number of peaks of the input waveform is 7 or more, (4) The sensor signal is being generated, that is, the sensor output voltage is less than 0.45 V for 100 ms, (5) When the five conditions that the peak generation time, that is, the sum of the seven peaks of the time from when the sensor output exceeds the reference voltage until the peak voltage occurs is 25 ms or less are satisfied, By prohibiting the data processing based on this, malfunction is prevented when a signal having a constant period with a sharp rise is input.

  As described above, conventionally, the determination is made based on the data from the time of signal generation until seven peaks occur, so the level of external noise falls within that time, and the condition for determining external noise When a certain periodicity cannot be acquired correctly, for example, when the level of external noise temporarily decreases as shown in the mountain of period T3 in FIG. 5 and the period becomes large, the maximum value of the period difference is 10 ms or less. Since the above condition is not satisfied, the above-mentioned logic does not operate, detection is not prohibited, and an intruder is erroneously detected.

  Also, the waveform when the intruder enters the vehicle, that is, the pick-up waveform happens to be a waveform that satisfies the above five conditions as shown in FIG. However, when a waveform with a constant and a peak time that does not change so much is detected, there is a problem that data processing, that is, intruder detection processing is prohibited.

  The present invention has been made in view of the above problems, and can prevent malfunction even when the level of external noise having a constant period with a steep rise is temporarily reduced and is not external noise. It is an object of the present invention to provide a data processing apparatus capable of executing data processing even when an input waveform temporarily satisfies an external noise determination condition.

  In order to achieve the above-described object, the data processing apparatus according to the present invention continuously performs the external noise determination based on the period difference and the peak generation time of the input signal when the rise time of the input waveform is within a predetermined time and the periods are different. I did it.

  That is, when the rise time of the input waveform is short and the period is different, as shown in FIG. 7, (1) 450 ms has not elapsed since the sensor output voltage became 0.45 V or more. (2) Input waveform The number of peaks is 7 or more, (3) the sensor signal is being generated, (4) the maximum period difference for the past 7 peaks is 10 ms or less, and (5) the peak occurrence time for the past 7 peaks is 25 ms. The following five conditions are determined in succession, and when all the conditions are satisfied, the satisfaction is held and data processing based on the sensor output is prohibited.

  In addition, even if it happens that an external noise determination condition is met with an accidental waveform, that is, a waveform with a constant period difference and a little change in time to peak is detected and data processing is prohibited, As shown in Fig. 6 (b), when the rise time to the peak that is not seen in the external noise occurs, that is, when the peak occurrence time for the past seven peaks is 25 ms or more, the above hold is performed. The data processing is executed after the release, and when the prohibition is once released in this way, the data processing is not prohibited even if the above five conditions are satisfied.

According to the data processing device of the present invention, when the rise time of the input waveform is within a predetermined time and the periods are different, the maximum value of the period difference of the input waveform and the peak occurrence time are determined by seven peaks of the input waveform. Therefore, even if the level of a signal having a constant period with a steep rise is temporarily lowered, data processing can be prohibited and malfunction can be prevented.
In addition, even if a waveform that happens to meet the above five conditions, that is, a waveform with a constant period difference and a little change in time to peak is detected and data processing is prohibited, When a rise time up to a peak that is not seen in the external noise occurs, the prohibition of data processing is canceled, so that erroneous prohibition of data processing can be prevented.

Hereinafter, an embodiment in which the data processing apparatus of the present invention is applied to an intrusion sensor of a security system will be described.
FIG. 8 is a block diagram showing the system configuration of the security system. This system is composed of an intrusion sensor 1, a security ECU 2, a horn 3, and the like. The intrusion sensor 1 spreads radio waves in the passenger compartment and the glass is broken. If a disturbance in the frequency of the radio wave is detected when a person moves in the passenger compartment, the security ECU 2 is notified, and the security ECU 2 performs an alarm operation by a horn 3 or a hazard lamp (not shown).

  The intrusion sensor 1 generates an oscillation circuit 11 that generates a high-frequency signal of 4 MHz, and multiplies and amplifies the output of the oscillation circuit 11 and outputs the output to the transmission antenna 13, and branches a part of the output signal to the mixing circuit 16. A multiplying / amplifying circuit 12, a receiving antenna 14 for receiving a reflected wave that is reflected when a transmission radio wave from the transmitting antenna 13 strikes a surrounding object, a receiving circuit 15 for receiving a signal from the receiving antenna 14, A mixing circuit 16 that mixes and outputs a reception signal from the reception circuit 15 and a transmission signal from the multiplication / amplification circuit 12, a detection circuit 17 that detects the mixed output from the mixing circuit 16, and an output of the detection circuit 17 is input. The sample hold circuit 18, the low frequency amplifier 19 to which the output of the sample hold circuit is input, the intermittent drive circuit 20, and the microcomputer 21 are included.

The microcomputer 21 extracts the frequency component of the difference between the reception signal and the transmission signal as a beat signal, and inputs an A / D converter 22 to which a signal from the low-frequency amplifier 19 that removes the offset voltage is input. The A / D conversion output of the D converter 22 is input, and a determination unit 23 that determines intrusion of a suspicious person, a periodic noise recognition unit 24, and an AND circuit 25 are included.
During the operation of the intrusion sensor 1, in order to reduce power consumption, the microcomputer 21 sends a signal to the intermittent drive circuit 20 at regular intervals, and when the intermittent drive circuit 20 receives a signal from the microcomputer 21, it oscillates for a certain period of time. The circuit 11 is driven.

  The output of the oscillation circuit 11 that generates a high frequency signal of 4 MHz is multiplied and amplified by the multiplication / amplification circuit 12 to a frequency signal of 24 GHz and is transmitted from the transmission antenna 13. The reflected wave that is reflected when the transmission radio wave from the transmission antenna 13 strikes a surrounding object is received by the reception antenna 14 and input to the reception circuit 15, and the reception signal from the reception circuit 15 and the transmission from the multiplication / amplification circuit 12 are received. The signal is mixed by the mixing circuit 16 and then detected by the detection circuit 17.

This detection signal is input to the low frequency amplifier 19 via the sample hold circuit 18, the frequency component of the difference between the reception signal and the transmission signal is input to the microcomputer 21 as a beat signal, and the microcomputer 21 outputs the output of the low frequency amplifier 19. Based on the A / D converted data, the presence or absence of unauthorized intrusion into the vehicle is detected by extracting the fluctuation of the waveform due to the movement of the object.
That is, the determination unit 23 performs a determination process based on the output of the A / D converter 22, for example, an intrusion determination process that detects the movement of a person and determines the presence of a person.

  On the other hand, the fixed-cycle noise recognizing unit 24 determines whether or not a signal with a sharp rising edge is input as a fixed-cycle signal based on the output of the A / D converter 22, and has a constant cycle with a sharp rising edge. When a signal is input, a high-level signal is output to the AND circuit 25, and output of the determination processing output of the determination unit 23 to the security ECU 2 is prohibited. The determination result is prevented from being input to the security ECU 2.

FIG. 9 is a diagram illustrating a hardware configuration for realizing the functions of the determination unit 23, the fixed-cycle noise recognition unit 24, and the AND circuit 25 of the microcomputer 21, and includes an A / D converter 22, a CPU 26, a ROM (Read Only Memory). ) 27 and RAM 28 (Random Access Memory).
The CPU 26 controls each part of the hardware of the microcomputer 21 and executes various programs such as a noise recognition program and an intrusion determination processing program based on programs stored in the ROM 27. The RAM 28 is composed of SRAM or the like, and stores temporary data generated when the program is executed, for example, a sampling value from the A / D converter 22, a period difference, and a time until a peak, and an intrusion detection prohibition flag Is stored in the flag storage area.
As described above, the determination unit 23, the fixed-cycle noise recognition unit 24, and the AND circuit 25 are configured by the CPU 26, the ROM 27, and the RAM 28, and their functions are executed by software.

Next, the operation of the fixed-cycle noise recognition unit 24 will be described with reference to the flowchart of FIG. 10 and the waveform diagrams of FIGS.
The CPU 26 constituting the periodic noise recognition unit 24 always determines whether or not the level of the input signal exceeds 0.45 V based on the A / D conversion output input every 0.5 ms from the A / D converter 22. As shown in FIG. 5, when the level of the input signal exceeds 0.45 V, the intrusion detection prohibition judging program shown in the flowchart of FIG. 10 is started and the sampling value from the A / D converter 22 is transferred to the RAM 28. Storage is started (step 101).

  Next, the CPU 26 determines whether or not seven or more peaks have occurred in the input waveform based on the sampling value stored in the RAM 28 (step 102). That is, as shown in FIG. 11, the CPU 26 counts up the number of peaks when the current sampling value is less than 0.45V and exceeds 0.45V, and counts up when it is not less than 0V from the previous count-up. By not counting, the number of peaks is counted, and by comparing this count value with 7, it is determined whether seven or more peaks have occurred.

  If it is determined in step 102 that seven or more peaks have not occurred, the CPU 26 determines whether 450 ms has elapsed since the start of the program (step 103), and 450 ms has elapsed since the start of the program. If it is determined that the sensor signal is not generated, it is determined whether or not the state in which the sensor signal is being generated, that is, the state where the sampling value is less than 0.45 V continues for 100 ms (step 104).

If it is determined that the state where the sampling value is less than 0.45 V does not continue for 100 ms, that is, the sensor signal is being generated, the CPU 26 returns to step 102 and determines whether seven or more peaks have occurred again. When it is determined that the sensor output voltage is less than 0.45 V for 100 ms, it is determined that the sensor output has been lost, and the stored values such as the detection prohibition flag and the sampling value are cleared (step 106), and then the program is executed. finish.
If it is determined in step 103 that 450 ms has elapsed since the program started, it is determined that no periodic noise has occurred, and output of the determination result of the suspicious person intrusion detection is permitted (step 105). ) After clearing the stored values such as the detection prohibition flag and the sampling value (step 106), the program is terminated.

  On the other hand, if it is determined in step 102 that seven or more peaks have occurred, the CPU 26, as shown in FIG. 5, has a period T1, T2,... After calculating T2-T1 |, | T3-T2 |,... (Step 107), the period difference for the past seven peaks is stored in the RAM 28 (step 108). If the period difference for the past seven peaks is already stored in the RAM 28, the value is updated.

Next, the CPU 26 stores or updates the maximum value Max of the period difference for the past seven peaks in the RAM 28 (step 109), then calculates a time integration value Tp up to the peak for the past seven peaks, and stores it in the RAM 28. Update (step 110).
That is, as shown in FIG. 12, the CPU 26 calculates the time tp1, tp2, tp3,... From the rising edge to the peak of the waveform, and calculates the integrated value Tp of the time tp from the rising edge to the peak of 7 peaks. Ask.

  When the above calculation is completed, the CPU 26 determines whether or not the time integration value Tp to the peak of the past seven peaks is smaller than 25 ms (step 111), and if it is determined that the time integration value Tp is larger than 25 ms, It is determined that a rise time up to a peak that is not seen in the periodic noise has occurred, and the output of the judgment result of the suspicious person's intrusion detection is permitted (step 105), and the stored values such as the detection prohibition flag and the sampling value are set. After clearing (step 106), the program is terminated.

  On the other hand, if it is determined in step 111 that the time integrated value Tp is smaller than 25 ms, the CPU 26 determines whether or not the maximum value Max of the period difference for the past seven peaks is smaller than 10 ms (step 112). When it is determined that the maximum value Max of the period difference of the minute is smaller than 10 ms, it is determined that the fixed period noise is generated with the signal having the fixed period and the signal rise is steep, and the detection prohibition flag in the flag storage area of the RAM 28 is set. Turns on (step 113).

  After turning on the detection prohibition flag, the CPU 26 determines whether or not the next peak of the input waveform has ended based on the sampling value stored in the RAM 28 (step 114), and the next peak has not ended. If it is determined, it is determined whether or not a sensor signal is being generated (step 115).

If it is determined in step 115 that the sensor signal is being generated, the CPU 26 returns to step 114 to determine whether or not the next mountain has ended again. If it is determined that the sensor signal is not generated, detection is prohibited. After clearing stored values such as flags and sampling values (step 106), the program is terminated.
If it is determined in step 114 that the next mountain has been completed, the process returns to step 107 and again calculates the maximum value Max of the period difference for the past seven peaks and the time integrated value Tp up to the peak for the past seven peaks. Then, it is determined whether or not the input signal is noise.

  On the other hand, if it is determined in step 112 that the maximum value Max of the period difference for the past seven peaks is greater than 10 ms, the CPU 26 temporarily reduces the level of the noise signal having a constant period with a sharp rise like period T3 in FIG. When the next peak ends, the maximum value Max of the period difference for the past seven peaks, and the time to the peak for the past seven peaks are again determined. The integrated value Tp is calculated to determine whether or not the input signal is noise.

  That is, if it is determined in step 112 that the maximum value Max of the period difference for the past seven peaks is greater than 10 ms, the CPU 26 determines whether or not the next peak of the input waveform has been completed based on the sampling value stored in the RAM 28. If it is determined that the next mountain has not ended (step 116), it is determined whether or not a sensor signal is being generated (step 117).

If it is determined that the sensor signal is being generated, the CPU 26 determines whether 450 ms has elapsed since the program was started (step 118), and determined that 450 ms has not elapsed since the program was started. If so, the process returns to step 116 to determine again whether or not the next peak of the input waveform has been completed.
If it is determined in step 116 that the next peak has been completed, the CPU 26 returns to step 107 and again the maximum value Max of the period difference for the past seven peaks, and the time integrated value up to the peak for the past seven peaks. Tp is calculated to determine whether or not the input signal is noise.

  If it is determined in step 117 that the sampling value is less than 0.45 V for 100 ms and no sensor signal is generated, the CPU 26 clears the stored values such as the detection prohibition flag and the sampling value (step 106). After that, the program is terminated.

On the other hand, if it is determined in step 118 that 450 ms has elapsed since the program started, the CPU 26 refers to the detection prohibition flag in the RAM 28 to determine whether or not the detection prohibition flag is on at that time. (Step 119), and when it is determined that the detection prohibition flag is on,
Since there is a possibility that the level of the noise signal having a constant period with a sharp rise may have temporarily decreased, the process returns to step 116 to determine again whether or not the next peak of the input waveform has been completed.

  If it is determined in step 119 that the detection prohibition flag is off, the CPU 26 determines that the input signal is not a noise signal and permits the output of the determination result of the suspicious person's intrusion detection (step 105). After clearing stored values such as flags and sampling values (step 106), the program is terminated.

As described above, when the rise time of the input waveform is short and the period is different, the maximum value of the period difference of the output signal of the sensor and the determination of the peak occurrence time of the output signal are performed every time the next peak is finished. Even when the level of a signal having a constant period with a steep rise is temporarily lowered, it is possible to prohibit detection of intrusion by a suspicious person and prevent malfunction.
That is, when a sensor signal as shown in FIG. 13 is generated, a large period difference is detected at the time P3 after transition to the signal present state, so detection is not prohibited even at the time P8 when data for seven peaks are confirmed. However, since the data for the past seven mountains satisfy the condition at P10, the intrusion detection of the suspicious person can be prohibited.

  Even if a waveform that happens to satisfy the condition, that is, a period difference is constant and the time until the peak does not change so much is detected and detection is prohibited, a fixed period is detected in step 111. When a rise time up to a peak that is not seen in noise occurs, detection prohibition is canceled and output of a judgment result of intrusion detection of a suspicious person is permitted, so that erroneous detection prohibition can be prevented.

Note that the number of peaks for noise determination, the voltage value for determining the presence / absence of a signal, the maximum value of the period difference, the determination value for the peak occurrence time, and the like described in the above embodiment are examples, and may be changed as appropriate. Is possible.
Further, in the above embodiment, the detection prohibition determination program is executed when the amplitude of the input signal becomes a certain value or more. However, if the period or time of the first waveform or several waveforms is not used, Noise detection can be performed only after the waveform is stabilized.

Furthermore, in the above embodiment, to calculate the period difference, the difference between the periods of the front and rear peaks is obtained, but the first one waveform is used as a reference value, and the difference between the period of the subsequent waveform and the reference value is calculated. By doing so, the period difference can also be obtained.
In the above embodiment, an example in which the data processing apparatus of the present invention is applied to a security system has been described. However, the data processing apparatus of the present invention is applied to a data processing apparatus that performs various waveform recognition other than the above. Is possible.

The block diagram which shows the structure of a general security system. The block diagram which shows the structure of an intrusion sensor. An example of a signal with a constant period and a sharp rising edge. A condition for determining a conventional signal having a constant period and a signal whose rising edge is steep. An example of a waveform when the conditions of FIG. 4 are not satisfied. An example of a pick-up waveform that is erroneously determined as noise. A condition for determining a signal having a sharp rise in a signal having a constant period according to the present invention. The block diagram which shows the system configuration | structure of a security system. The figure which shows the hardware constitutions of a microcomputer. The flowchart which shows the effect | action of a fixed period noise recognition part. Explanatory drawing of the count of the number of the peaks of a waveform. Explanatory drawing for calculating | requiring the integrated value of the time from the rise of a waveform to a peak. An example of a waveform in which a detection prohibition flag is turned on.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Intrusion sensor 11 Oscillation circuit 12 Multiplication / amplification circuit 13 Transmission antenna 14 Reception antenna 15 Reception circuit 16 Mixing circuit 17 Detection circuit 18 Sample hold circuit 19 Low frequency amplifier 20 Intermittent drive circuit 21 Microcomputer 22 A / D converter 23 Determination part 24 Periodic noise recognition unit 25 AND circuit 2 Security ECU
3 Horn

Claims (6)

Data processing means for processing the A / D conversion output of the input signal;
When the waveform having the same period is continuously input and the rise time of the waveform is determined to be within the predetermined time, the external noise determination means for determining the external noise is provided,
When the external noise is determined to be external noise, the external noise determination means prohibits the data processing of the data processing means, and when the waveform rise time is within a predetermined time and the period is different, the external noise determination means is continuously external. A data processing apparatus that performs noise determination. The data processing apparatus according to claim 1, wherein
The external noise determination means determines whether or not the noise is external noise based on the period difference and rise time of a plurality of peaks of the input signal, and if the rise time is within a predetermined time and the period is different, the next peak is finished. Then, the data processing apparatus is characterized in that it is determined again whether or not the noise is an external noise based on a period difference between plural peaks and a rise time. In the data processing device according to claim 1 or 2,
A data processing apparatus, wherein if the input signal cannot be determined to be external noise within a predetermined time after the input signal is generated, the data processing means starts data processing. In the data processing device according to any one of claims 1 to 3,
In the data processing prohibited state, when it is determined that the rise time of the waveform has reached a predetermined time or more, the external noise determination unit cancels the data processing prohibition and does not prohibit the subsequent data processing. Processing equipment.   A security device comprising the data processing device according to claim 1.   An intrusion sensor comprising the data processing device according to claim 1.

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