JP5564657B2 - Microwave detector and program - Google Patents

Description

  The present invention relates to a microwave detector that issues an alarm when microwaves emitted from a detection target such as a vehicle speed measurement device are received.

A microwave detector for detecting and notifying a microwave transmitted from a vehicle speed measuring device is well known. This microwave detector receives and recognizes microwaves from the vehicle speed measurement device even when it receives microwaves sent from a false alarm source such as an automatic door using the same frequency band as the vehicle speed measurement device. As a result, there is a problem that an unnecessary alarm is issued. In view of such circumstances, recent microwave detectors store position information of false alarm sources, recognize the position of the vehicle by GPS, and generate microwaves when the vehicle is positioned at the false alarm source. By controlling not to issue an alarm even if detected, an attempt is made to prevent issuing an unnecessary alarm.
There is an invention disclosed in Japanese Patent Application Laid-Open No. H10-228443 as one that automatically stores the location information of such false alarm sources. The present invention issues a warning when receiving a microwave of a predetermined frequency band, and outputs position information output from a position detector that detects the current position of the vehicle when the received microwave satisfies a predetermined condition. Is stored in the malfunction source position storage unit as malfunction source position information, and then microwaves when passing through the same location (if within a predetermined distance of the position information stored in the malfunction source position storage unit) Is received, the position information of the false alarm source is automatically registered by suppressing the normal alarm operation. Furthermore, if the microwave is not received at the location of the stored false alarm source position information, the location previously stored as the false alarm source position information is the false alarm source position stored as not being the false alarm source. Erase information. This means that microwaves sent from false alarm sources such as automatic doors are considered to be constantly sent, whereas microwaves from mobile vehicle speed measuring devices are not always output. It uses properties.

JP 2006-046976 A

  However, in this method, when microwaves are received, an alarm is not issued when the received location is a location stored as false alarm source location information, so the false alarm source location information is stored. In the first place, there is a problem that an alarm is issued even if it is a false alarm source. For example, if there is a false alarm source in the place where it passes for the first time, an alarm is always notified. That is, in the invention disclosed in Patent Document 1, it is impossible to avoid the first false alarm.

  Furthermore, even if the position is registered as a false alarm source, there is a problem that the false alarm source position information may be erased depending on the reception state of the microwave when passing the position for the second time or later. there were. That is, for example, microwaves are periodically emitted from a human sensor attached to an automatic door that is one mode of a false alarm source. Normally, this human sensor operates during store sales and emits microwaves, but microwaves are not emitted after the end of business. Therefore, even if an automatic door is registered as a false alarm source once by the invention disclosed in Patent Document 1, it passes after the automatic door during a period when microwaves are not released after the end of business. In this case, since the microwave is not received, the false alarm source position information about the automatic door is deleted. Therefore, if it passes again in front of the automatic door during business hours such as daytime, an alarm will be output when microwaves are received.

  Furthermore, because there is a limit on the number of false alarm source position information that can be registered due to the relationship with the memory capacity of the memory, an alarm is issued even when microwaves emitted from false alarm sources that cannot be registered exceeding the limit are received. It will be.

  The present invention has been made in view of the above-mentioned problems, and can identify a false alarm source more reliably than the conventional method, and can suppress the output of an alarm even before the false alarm source that passes for the first time. An object of the present invention is to provide a microwave detector and a program that can be used.

  In order to achieve the above-described object, a microwave detector according to the present invention is based on (1) microwave detection means for detecting a predetermined microwave, and detection of the predetermined microwave by the microwave detection means. A microwave detector comprising a control means for controlling an alarm using an alarm means, comprising a leaked radio wave detection means for detecting a leaked radio wave from the source of the predetermined microwave, wherein the control means comprises: When the predetermined microwave is detected by the microwave detection means, if the characteristic of the leaked radio wave detected by the leaked radio wave detection means does not correspond to the characteristic of the false alarm source set in advance, a normal alarm is issued. Informs and suppresses the normal alarm when the characteristic of the leaked radio wave detected by the leaked radio wave detection means corresponds to the characteristic of the false alarm source set in advance. It was Gosuru way. Suppressing regular alarms includes reducing alarm levels (decreasing volume / simplifying display, etc.) as well as not alarming, and various aspects such as alarming in different modes. is there. The control means corresponds to the analysis determination unit 30 in the embodiment. The leaked radio wave detection means corresponds to the multiplied microwave band receiver 22 in the embodiment. Moreover, you may make it include the multiplication microwave frequency measurement part 24 and the multiplication microwave receiving intensity measurement part 26 in a leakage electric wave detection means.

  For example, false alarm sources such as automatic doors have a simpler microwave transmission function and circuit and are less accurate than detection objects such as vehicle speed measuring devices. For example, when compared with the leaked radio wave from the detection target, the leaked radio wave from the false alarm source can be identified. Therefore, according to the present invention, even if the microwave transmitted from the false alarm source is detected by the microwave detection means as the microwave to be alarmed, the characteristics of the leaked radio wave from the false alarm source If is detected, no alarm is issued. Thus, since the presence or absence of an alarm is controlled based on the characteristics of leaked radio waves, a false alarm source can be identified more reliably than in the conventional method, and a microwave detector with fewer false alarms can be provided.

  (2) In order to further reduce false alarms, position detection means for detecting the position of the own vehicle, and information on the position of the own vehicle detected by the position detection means when the alarm is suppressed is falsely alarmed. False alarm source position information storage means for storing as a source position, wherein the alarm notification means detects the vehicle detected by the position detection means when a predetermined microwave is detected by the microwave detection means. When the position is within a predetermined range from the position of the false alarm source stored in the false alarm source position information storage means, the alarm notification may be suppressed. In this case, for example, when the own vehicle enters a predetermined range from the position of the false alarm source stored in the false alarm source position information storage means, the predetermined microwave is detected by the microwave detection means. In such a case, even if the vehicle is in a position where the leaked radio wave detection means has not yet detected the leaked radio wave, the normal alarm is suppressed and further false alarms can be prevented.

  In addition, once the alarm is suppressed, the control means may be configured to continue the suppression of the alarm until a predetermined time elapses or a predetermined distance is moved. In this way, after the alarm is suppressed, the false alarm can be continuously suppressed even when the leaked radio wave is not detected due to the presence of an obstacle or the like. The control means is a case where a predetermined microwave is detected by the microwave detection means, and the characteristic of the leaked radio wave detected by the leaked radio wave detection means does not correspond to the characteristic of the false alarm source set in advance. Is a predetermined time (for example, the time from when the radio wave from the false alarm source is detected by the microwave detecting means until the characteristic of the leaked radio wave detected by the leaked radio wave detecting means is determined to correspond to the characteristic of the false alarm source. It is good also as a structure which does not alert | report (it reserves) until it passes (time corresponding to (time lag)) or it moves a predetermined distance. In this way, even if the microwave generated by the false alarm source is strong, the leaked radio wave is weak, only the predetermined microwave is detected, and the leaked radio wave has not been detected yet, False alarms can be prevented.

  (3) Further, as a characteristic of leaked radio waves, for example, frequency distribution characteristics of leaked radio waves can be used. In particular, the characteristics of the leaked radio wave may be based on the frequency and intensity of the leaked radio wave of the alarm target device that emits a predetermined microwave and the frequency and intensity of the leaked radio wave of the false alarm source. For example, when a predetermined microwave is detected by the microwave detection unit, the control unit sets a ratio between the intensity of the radio wave detected by the microwave detection unit and the intensity of the leaked radio wave detected by the leaked radio wave detection unit. Based on this, it may be determined whether to suppress the regular alarm. That is, the determination may be made based on purity.

  (4) Further, for example, when a predetermined microwave is detected by the microwave detection means, the control means compares the intensity of the leaked radio wave detected by the leaked radio wave detection means with a preset reference intensity, The alarm may be notified when the intensity of the leaked radio wave is less than the reference intensity, and the alarm may not be notified when the intensity is higher than the reference intensity. The reference intensity may be determined based on the difference between the leaked radio wave intensity in the target speed measurement device and the false alarm source leaked radio wave intensity. Usually, the intensity of the leaked radio wave from the false alarm source is stronger than the intensity of the leaked radio wave from the vehicle speed measuring device that is the alarm target, so that the reference intensity can be set based on the difference in intensity.

  (5) Further, the leaked radio wave to be detected may be a radio wave corresponding to unnecessary radiation and spurious emitted by a false alarm source, or a radio wave having an image frequency of a local oscillator of the false alarm source. However, in particular, it is preferable to detect a radio wave having a frequency within a predetermined range estimated as a predetermined microwave harmonic (multiplied harmonic / n-th harmonic) as a leaked radio wave. The false alarm source, such as an automatic door, emits its multiplied harmonics together with a predetermined microwave of the frequency generated by the false alarm source (that is, a frequency that substantially matches the predetermined frequency of the alarm target), whereas the vehicle speed This is because the frequency-multiplied harmonic of a predetermined microwave is suppressed from an alarm target device such as a measurement device, and the emission intensity of the harmonic is relatively weak compared to the false alarm source.

  (6) Position detection means for detecting the current position, and the current detected by the position detection means when the characteristics of the leaked radio wave detected by the leaked radio wave detection means correspond to the characteristics of a preset false alarm source False alarm source position storage means for storing and holding the position as a false alarm source position, and the control means has a current position when the microwave is detected by the microwave detection means, the false alarm source position storage means It is preferable to provide a function of suppressing the notification of a normal alarm when it is within the reference distance from the false alarm source position stored in the above. According to the invention described in (1) to (5) above, when a false alarm source is detected once, it is based on microwaves from the same false alarm source for the second and subsequent times by storing and holding the position. Generation of false alarms can be efficiently and accurately suppressed. The present invention is realized by the embodiment shown in FIG.

(7) If the area where the predetermined microwave is received by the microwave detection means is less than the reference position detection means for detecting the current position, the current position detected by the position detection means is the source of malfunction. False alarm source position storage means for storing as a position, and the control means is a false alarm in which the current position when the microwave is detected by the microwave detection means is stored in the false alarm source position storage means. In the case where the distance is within the reference distance from the source position, it is preferable to provide a function of suppressing notification of a regular alarm.
A microwave emitted from an automatic door, which is an example of a false alarm source, has a strong directivity and is set downward. Therefore, the reception distance is extremely short compared to a vehicle speed measurement device that is a detection target (microwave). The wave arrival area is narrow). As an example, the vehicle speed measuring device has a reach distance of 500 m or more, but in the case of an automatic door, it is about several tens of meters. Therefore, the area (distance) where the microwaves emitted from the same transmission source are received from the history of reception of the microwaves, etc., and if the area is below the standard (for example, 100 m), the microwave from the false alarm source It can be judged that there was. Therefore, in such a case, in the subsequent alarm control, as in the invention of (6), based on the registered false alarm source position information, errors based on microwaves from the same false alarm source for the second and subsequent times are used. The generation of alarms can be suppressed efficiently and accurately. Further, by providing this function, for example, even when it is determined as a detection target by determination based on leaked radio waves, it can be determined again that it is from a false alarm source when the reception area is narrow.

  In the present invention, the false alarm source can be identified more reliably than in the conventional method, and the false alarm output accompanying the microwave detection can be suppressed even before the false alarm source passing for the first time.

1 is a block diagram illustrating a preferred embodiment of the present invention. It is a flowchart which shows the function of the analysis determination part 30 of this embodiment. It is a flowchart which shows the function of the analysis determination part 30 of this embodiment. It is a block diagram which shows other embodiment of this invention. It is a figure which shows a modification.

  FIG. 1 shows a preferred embodiment of the microwave detector of the present invention. The microwave detector according to the present embodiment uses a microwave having a frequency band of 10.525 GHz ± 15 MHz emitted from the vehicle speed measurement device as a detection target. On the other hand, the frequency band of microwaves emitted from a false alarm source such as an automatic door is 10.525 GHz ± 25 MHz.

  As shown in FIG. 1, a detection target microwave band receiving unit 12 that receives microwaves in the detection target frequency band, and a reception frequency of the microwaves received by the detection target microwave band reception unit 12 (hereinafter referred to as this reception). The detection target microwave reception frequency measurement unit 14 that measures the frequency “detection target microwave frequency fa” and the reception intensity of the microwave received by the detection target microwave band reception unit (hereinafter, this reception intensity is “detected”). And a detection target microwave reception intensity measuring unit 16 for measuring the target microwave reception intensity La ”.

  Separately from this, a frequency-multiplying microwave that receives the frequency band of the second harmonic of the microwave that can be received by the detection-target microwave band receiver 12 (the frequency should be 21.1050 GHz ± 50 MHz or more). A waveband receiver 22 and a multiplied microwave reception frequency measuring unit 24 for measuring a reception frequency of the microwave received by the multiplied microwaveband receiver (hereinafter, this reception frequency is referred to as “multiplied microwave reception frequency fb”); The microwave reception intensity measurement unit 26 for measuring the reception intensity of the microwave received by the multiplication microwave band reception unit (hereinafter, this reception intensity is referred to as “multiplication microwave reception intensity Lb”) is provided.

  Then, the detection target microwave frequency fa measured by the detection target microwave reception frequency measurement unit 14, the detection target microwave reception intensity La measured by the detection target microwave reception intensity measurement unit 16, and the multiplied microwave reception frequency measurement unit 24. Input the multiplied microwave reception frequency fb measured in 24 and the multiplied microwave reception intensity Lb measured by the multiplied microwave reception intensity measuring unit 26, and analyze and determine whether to issue an alarm based on these states. An analysis determination unit 30 that performs an alarm display when the analysis determination unit 30 determines to perform an alarm, and an alarm sound output unit 44 that outputs an alarm sound. Alarm sounds include buzzer and voice.

  In the conventional microwave detector, the frequency band of the detection target microwave is set as a reception target, and the received microwave is detected based on only the received signal. It is determined whether or not it is a microwave, and an alarm is issued when it is determined that the detection target microwave has been received.In this embodiment, in addition to the frequency band of the detection target microwave, Monitor the frequency band in which microwaves with double the frequency (double harmonics / multiplication waves) exist, and from the relationship of microwaves received at the same timing (simultaneous, within a certain time difference) in the two frequency bands Then, it is determined whether or not the microwave received by the detection target microwave band receiving unit 12 is emitted from a speed measurement device or the like that is the detection target. Such determination is performed by the analysis determination unit 30, and specifically, is performed by the following algorithm.

When the analysis determination unit 30 receives a microwave having a certain level of the detection target microwave frequency fa having a predetermined frequency band and the detection target microwave reception intensity La equal to or higher than a preset threshold value, It is assumed that it is determined that there is a speed measurement device that is a detection target, and the alarm indicator 42 and the alarm sound output unit 44 are operated to notify a predetermined alarm. When the detection target microwave frequency fa, the detection target microwave reception intensity La, the multiplied microwave reception frequency fb, and the multiplied microwave reception intensity Lb are monitored, and all the following conditions (1) and (2) are satisfied In addition, it is determined that a false alarm source such as an automatic door has been received. That is, it is determined that the detected microwave is not the alarm target microwave (not the microwave emitted by the speed measurement device). And when it determines with it being reception of a false alarm source, the analysis determination part 30 performs control which does not output the alarm to said alarm display part 42 and the alarm sound output part 44. FIG.
(1) The time difference between when the detection target microwave reception intensity La exceeds the intensity reference value L1 and when the multiplied microwave reception intensity Lb exceeds the intensity reference value L2 is within the reference time T1.
(2) The multiplied microwave reception frequency fb is approximately twice the frequency of the detection target microwave frequency fa.

  That is, in the case of a false alarm source such as an automatic door, the accuracy of an oscillation circuit, a transmission circuit, etc. is lower than that of a vehicle speed measurement device. A microwave of the wave component is emitted. Accordingly, the microwave of the fundamental frequency and the microwave of the harmonic component (here, the multiplied microwave: second harmonic) are output at the same time. Therefore, when the condition (1) is satisfied, the multiplied microwave band There is a possibility that the microwave received by the receiving unit 22 is a multiplied microwave based on the microwave received by the detection target microwave band receiving unit 12. In other words, when the condition (1) is not satisfied, the two microwaves received by the respective microwave band receivers 12 and 22 can be regarded as microwaves transmitted from different transmission sources. Note that the time difference within the reference time T1 is allowed because, for example, a system for receiving a microwave and processing a signal is different from each other, which may cause a signal processing shift in the microwave detector. This is because the detection timings of the microwaves output from the same false alarm source and the multiplied microwaves thereof are not always the same.

  When the condition (2) is further satisfied, the microwave received by the multiplied microwave band receiving unit 22 is estimated to be a multiplied microwave based on the microwave received by the detection target microwave band receiving unit 12. it can. In other words, when the condition (2) is not satisfied, the two microwaves received by the respective microwave band receivers 12 and 22 can be regarded as microwaves transmitted from different transmission sources. That is, the frequency band that can be received by the detection target microwave band receiver 12 has a certain width. Similarly, the frequency band receivable by the multiplied microwave band receiver 22 has a certain width. Therefore, even if the microwaves are received by the receiving units 12 and 22 at the same timing, two microwaves transmitted from the respective separate transmission sources happen to be received by the microwave band receiving units 12 and 22. If it is a possible frequency band, the condition of (1) is satisfied. However, if the microwave of the fundamental frequency and the multiplied microwave are from the same transmission source, the relationship is fb = 2 × fa. If the above condition is not satisfied, it can be said that the microwaves from the separate transmission sources are received. From the relationship of reception accuracy and signal processing, even if it is a multiplied microwave, its frequency does not always exactly match twice the frequency of the microwave received by the detection target microwave band receiving unit 12. It is good to have a certain tolerance.

  The intensity reference value L1 is a value obtained by measuring the value of the detection target microwave reception intensity La when receiving the detection target microwave output from the vehicle speed measurement device that is actually installed. Set to. That is, a value that allows discrimination between when no microwave is received and when it is received from the vehicle speed measuring device is set.

  The intensity reference value L2 is obtained by measuring the value of the multiplied microwave reception intensity Lb when receiving the multiplied microwave (second harmonic) output from the false alarm source (for example, automatic door). Set to value. That is, a value is set that allows discrimination between when no microwave is received and when it is received from the false alarm source. Furthermore, this multiplied microwave exists also in the microwave radiated | emitted from the vehicle speed measuring apparatus which is a regular detection target. However, since the transmission circuit of the vehicle speed measuring device is highly accurate, the leakage level of the multiplied microwave is smaller than that of the automatic door. Therefore, the intensity reference value L2 is set to a value that is greater than the level of the multiplied microwave output from the vehicle speed measurement device and that can discriminate both.

  Further, the reference time T1 is, for example, close to the false alarm source from a distance, and when the detection target microwave reception intensity La exceeds the intensity reference value L1, the multiplied microwave reception intensity Lb exceeds the intensity reference value L2. Set time to hour. That is, it is set to a time from when it is determined that the detection target microwave emitted by the false alarm source is received (La> L1) until it is determined that the multiplied microwave emitted by the false alarm source is received (Lb> L2). To do. Such control may be performed by a circuit, or may be controlled by processing of the microcomputer using a microcomputer as the analysis determination unit 30.

  Next, an example of the flow of processing when the analysis determination unit 30 having a determination processing function for determining whether or not the above condition is satisfied is configured with a microcomputer will be described with reference to FIG. First, the analysis determination unit 30 determines whether or not the detection target microwave reception intensity La exceeds the intensity reference value L1 (S110). When the detection target microwave reception intensity La does not exceed the intensity reference value L1 (S110: NO), the process returns to S110. On the other hand, when the detection target microwave reception intensity La exceeds the intensity reference value L1 (S110: YES), the process proceeds to S120.

  The analysis determination unit 30 resets the timer value t (t = 0) and starts the timer (S120). Then, the analysis determination unit 30 determines whether or not the multiplied microwave reception intensity Lb exceeds the intensity reference value L2 (S130). When the multiplied microwave reception intensity Lb does not exceed the intensity reference value L2, the process proceeds to S140.

  Next, the analysis determination unit 30 determines whether or not the timer value t has exceeded the reference time T1 (S140), and if not (S140: NO), returns to S130. On the other hand, when the timer value t exceeds the reference time T1 (S140: YES), the above condition (1) is not satisfied (not a microwave from a false alarm source = reception of a microwave from a detection target) Therefore, the process proceeds to S160, and the analysis determination unit 30 performs an alarm process in which an alarm is displayed on the alarm display unit 42 and an alarm sound is output from the alarm sound output unit 44.

  On the other hand, when the multiplication microwave reception intensity Lb exceeds the intensity reference value L2 in the branch determination of S130 (S130: YES), two microwaves are received before the timer value t expires (t> T1). Therefore, the above condition (1) is satisfied, and the process proceeds to S150. Then, the analysis determination unit 30 determines whether or not the multiplied microwave reception frequency fb is approximately twice the frequency of the detection target microwave frequency fa (S150). Specifically, it is determined whether or not 2fa−fd <fb <2fa + fd (fd is 1 MHz, for example). If the multiplied microwave reception frequency fb is not about twice the frequency of the detection object microwave frequency fa (S150: NO), the microwave received by the multiplication microwave band reception unit 22 is the detection object microwave band reception unit 12. Therefore, the process proceeds to S160, and the above-described alarm processing is performed. On the other hand, if the multiplied microwave reception frequency fb is about twice the detection target microwave frequency fa (S150: YES), the above condition (2) is also satisfied (the microwave being received, the error Therefore, since the microwave received by the detection target microwave band receiving unit 12 can be estimated as the microwave from the false alarm source, the process returns to S110 without performing an alarm.

  By such processing, an alarm is not issued while the detection target microwave reception intensity La does not exceed the intensity reference value L1. Further, the detection target microwave reception intensity La exceeds the intensity reference value L1 (S110: YES), and within the reference time T1 after the detection target microwave reception intensity La exceeds the intensity reference value L1 (S140: NO), multiplication is performed. When the microwave reception intensity Lb exceeds the intensity reference value L2 (S130: YES) and the multiplied microwave reception frequency fb is approximately twice the detection target microwave frequency fa (S150: YES), an alarm is issued. Can be suppressed.

  On the other hand, although the detection target microwave reception intensity La exceeds the intensity reference value L1 (S110: YES), multiplication is performed even if the reference time T1 elapses after the detection target microwave reception intensity La exceeds the intensity reference value L1. When the microwave reception intensity Lb does not exceed the intensity reference value L2 (S130: NO, S140: YES), an alarm can be notified because the condition (1) is not satisfied. Further, even when the multiplied microwave reception frequency fb is not approximately twice the frequency of the detection target microwave frequency fa (S150: YES), the alarm can be notified because the condition (2) is not satisfied.

  Also, the analysis determination unit 30 is the time when the detection target microwave reception intensity La exceeds the intensity reference value L1, and when the multiplied microwave reception intensity Lb does not exceed the intensity reference value L2, until the reference time T1 elapses. Since the alarm is not notified (reserved), for example, the microwave (frequency fa) generated by the false alarm source is strong, the multiplied microwave (frequency fb≈2fa) is weak, and the false alarm source Even when only the emitted microwave (frequency fa) is detected and the multiplied microwave is not yet detected, a false alarm can be prevented.

  In the above-described embodiment, the alarm is not notified (reserved) until the reference time T1 elapses. However, instead of this, the analysis determination unit 30 detects the movement distance and detects this movement. A configuration may be adopted in which an alarm is not notified (reserved) until the distance reaches a predetermined reference distance D1.

  For example, when the analysis determination unit 30 suppresses the alarm (in the case of S150: YES in FIG. 2 or S180: YES in FIG. 3 described later), until the predetermined time elapses or the predetermined distance is moved, It is good to make it the structure which continues suppression of an alarm (For example, wait processing for 5 seconds is inserted before returning to S110). In this way, even after the alarm is suppressed, even if the multiplied microwave is not detected due to the presence of an obstacle, the false alarm can be continuously suppressed.

  In the present embodiment, the alarm is configured to be issued in S160. Instead, for example, the alarm is started in S160 (the alarm is continued if the alarm is already in progress), and S150: YES. And S110: It is good also as a structure which stops an alarm in the case of NO. Furthermore, in the present embodiment, as an example of suppressing an alarm, an example of performing a process that does not perform an alarm is given. For example, the microwave reception intensity La measured by the microwave reception intensity measurement unit is equal to or greater than a predetermined value. In this case, a hardware configuration for outputting an alarm from the alarm display unit 42 and the alarm sound output unit 44 is used, and this output is suppressed when the conditions (1) and (2) are satisfied (for example, output is stopped). Alternatively, the alarm sound volume may be lowered). Furthermore, as a mode for suppressing the alarm, a different type of alarm (such as an alarm in which the reception of the microwave from the false alarm source is known) may be performed while stopping the normal alarm. In this way, even when it is determined that the microwave from the false alarm source is received, the user (driver) is notified that the microwave is received by issuing some sort of alarm that is not a regular alarm. Can do. That is, for example, there is a possibility that a microwave from a malfunctioning source and a microwave emitted from a detection target such as a vehicle speed measuring device may be received simultaneously. In such a case, the conditions (1) and (2) are satisfied. If this happens, the normal alarm will be suppressed, but by issuing some alarm, the driver can be notified that there is a possibility of the above.

Further, for example, in addition to the conditions (1) and (2) described above, one or both of the following conditions (3) and (4) may be added. That is, when all of the conditions (1) to (4) are satisfied, it may be determined that a false alarm source such as an automatic door is received, or (1), (2), (3) When all the conditions or all the conditions (1), (2), and (4) are satisfied, it may be determined that a false alarm source such as an automatic door is received.
(3) The detection target microwave reception intensity La is greater than the multiplied microwave reception intensity Lb.
(4) The difference between the detection target microwave reception intensity La and the multiplied microwave reception intensity Lb is within a predetermined intensity difference allowable range (Ldmin <La−Lb <Ldmax: Ldmin is the minimum allowable intensity difference, and Ldmax is the maximum allowable intensity difference) Value).

  That is, for a harmonic (multiplied microwave) of a certain microwave (fundamental wave), the received intensity of the multiplied microwave is lower than the received intensity of the basic microwave. In other words, when the reception intensity of the microwave received by the multiplied microwave band receiving unit 22 is higher than the reception intensity of the microwave received by the detection target microwave band receiving unit 12, the multiplied microwave band It can be said that the microwave received by the receiving unit 22 is not a multiplied microwave. Therefore, by adding the above condition (3) to the determination condition, it is possible to more accurately determine whether the microwave is from the false alarm source.

  Similarly, in the case of a false alarm source such as an automatic door, as described above, the received intensity of the harmonic component is relatively larger than the received intensity of the harmonic component emitted from the detection target such as the vehicle speed measuring device. Become. Therefore, it is assumed that the difference between the reception intensity of the microwave that is the fundamental wave received by the detection target microwave band reception unit 12 and the reception intensity of the multiplication microwave received by the multiplication microwave band reception unit 22 is a false alarm. The source is smaller. Therefore, by adding the above condition (3) to the determination condition, it is possible to more accurately determine whether the microwave is from the false alarm source.

  For example, the allowable intensity range is set as follows. That is, the detection target microwave reception intensity La and the multiplied microwave when receiving the detection target microwave output from the speed measurement device at a predetermined distance (for example, 20 m) from the actually installed speed measurement device. The received intensity Lb is measured in advance, and this difference is defined as a speed measuring apparatus intensity difference Lds. On the other hand, at the point of a predetermined distance (for example, 30 m) at which the microwave from the false alarm source can be received, the detection target microwave reception intensity La and the multiplied microwave reception when the microwave output from the false alarm source is received. The intensity Lb is measured in advance, and this difference is defined as a false alarm source intensity difference Ldn. The maximum allowable intensity difference value Ldmax is set to a value that can discriminate between the speed measuring device intensity difference Lds and the false alarm source intensity difference Ldn (for example, an intermediate value between them (Ldmax = (Lds + Ldn) / 2)). Set. The minimum intensity difference allowable value Ldmin is a difference value between the microwave reception intensity La and the multiplied microwave reception intensity Lb near the false alarm source (for example, 1 m).

  For example, when both the determinations of (3) and (4) are performed by the microcomputer of the analysis determination unit 30, for example, as shown in FIG. 3, processing shown in S170 and S180 is added to the processing of FIG. This can be achieved. That is, after the process of S150 described above, the process proceeds to S170, and the analysis determination unit 30 determines whether or not the detection target microwave reception intensity La is greater than the multiplied microwave reception intensity Lb (S170). When the detection target microwave reception intensity La is equal to or lower than the multiplied microwave reception intensity Lb (S170: NO), the analysis determination unit 30 proceeds to S160 and issues an alarm. On the other hand, when the detection target microwave reception intensity La is larger than the multiplied microwave reception intensity Lb (S170: YES), the process proceeds to S180. Then, the analysis determination unit 30 determines that the difference between the detection target microwave reception intensity La and the multiplied microwave reception intensity Lb is within a predetermined intensity difference allowable range (Ldmin <La−Lb <Ldmax: Ldmin is an allowable intensity difference minimum value, Ldmax (S180). If it is not within the tolerance range, the process proceeds to S160, and the analysis determination unit 30 issues an alarm. On the other hand, if the intensity difference is within the allowable range, no alarm is issued and the process returns to S110.

  If the condition (3) is added, an alarm is issued when the detection target microwave reception intensity La is equal to or lower than the multiplied microwave reception intensity Lb. If the condition (4) is added, an alarm is issued even if the difference between the detection target microwave reception intensity La and the multiplied microwave reception intensity Lb is not within the allowable intensity range. Therefore, it is possible to discriminate whether it is a false alarm source or a speed measuring device more accurately, and it is possible to prevent a situation where a warning is not issued even though it is a microwave transmitted from a speed measuring device that originally requires an alarm. can do.

  The intensity reference value L1, the intensity reference value L2, the reference time T1, and the intensity allowable range Ld may be determined using values of a specific vehicle speed measuring device or a specific false alarm source, but a large number of vehicle speeds. It is even better to make fine adjustments to values that are suitable for overall discrimination based on values measured by measuring devices and false alarm sources.

  The above-mentioned reference values (L1, L2, t, fd, Ldmin, Ldmax) are: (1) Difference in intensity between frequency intensity used and frequency intensity used in vehicle speed measuring device, (2) Frequency used in control device of receiver And (3) the difference between the sensitivity of the multiplied frequency and (3) the difference between the frequency of use of the control device and the attenuation of the multiplied frequency during spatial propagation. In addition, (4) it is preferable to increase the dynamic range so as not to saturate the site where La and Lb are obtained.

  When the analysis determination unit 30 is configured without using a microcomputer, for example, the detection target microwave frequency fa measured by the detection target microwave reception frequency measurement unit 14 and the detection target microwave reception intensity measurement unit 16 are used. The measured microwave reception intensity La measured, the multiplication microwave reception frequency fb measured by the multiplication microwave reception frequency measurement unit 24, and the multiplication microwave reception intensity Lb measured by the multiplication microwave reception intensity measurement unit 26 are stored. And a comparator that compares these values stored in the storage unit under the conditions (1) to (4) described above may be provided for comparison and determination.

  FIG. 4 shows yet another embodiment. As shown in FIG. 4, in this embodiment, in addition to the configuration shown in FIG. A false alarm source position information storage unit 54 is provided for possible storage.

  The analysis determining unit 30 then detects the detection target microwave frequency fa measured by the detection target microwave reception frequency measurement unit 14 and the detection target microwave reception intensity La measured by the detection target microwave reception intensity measurement unit 16. The multiplication microwave reception frequency fb measured by the multiplication microwave reception frequency measurement unit 24 and the multiplication microwave reception intensity Lb measured by the multiplication microwave reception intensity measurement unit 26 are input, and an alarm is issued based on these states. Whether or not it is analyzed. When the analysis determination unit 30 determines not to issue an alarm (for example, in the case of S150: YES in FIG. 2 or S170: YES in FIG. 3), the position information of the vehicle detected by the position detection unit 52 ( For example, information corresponding to latitude, longitude, altitude, etc.) is stored in the false alarm source position information storage unit 54 as false alarm source position information. When the detection target microwave reception intensity La exceeds the intensity reference value L1 (for example, in the case of S110: YES in FIGS. 2 and 3), the position information of the own vehicle detected by the position detection unit 52 is the false alarm source. When it corresponds to the vicinity of the false alarm source position information stored in the position information storage unit 52 (for example, in a circle with a radius of 50 m centering on the position indicated by the false alarm source position information), a process for suppressing the alarm is performed ( For example, in the case of the processes of FIGS. 2 and 3, the process returns to S110). In this way, an alarm is not issued in the vicinity of a point that has passed in the past and registered as a false alarm source, so that a false alarm can be further prevented.

  The false alarm source position information stored in the false alarm source position information storage unit 54 is not limited to that detected based on the leaked radio wave as described above. For example, the detection target microwave reception frequency measurement unit 14 The period during which the microwaves whose radio wave intensity and frequency satisfy a predetermined condition are received based on the detection target microwave frequency fa measured in step 1 and the detection target microwave reception intensity La measured by the detection target microwave reception intensity measurement unit 16 (Area / Distance) may be obtained, and when the area is narrow (short) below the reference, the current position detected by the position detector 52 may be stored as a malfunction source position.

As described above, the characteristic of leaked radio waves is that the reception intensity of the leaked radio waves is greater in the microwave from the false alarm source, so the received radio wave reception intensity of each detected microwave and leaked radio wave Based on the ratio, it is possible to discriminate whether or not it is a microwave from a false alarm source. That is, the analysis determination unit 30 is configured to detect the intensity of the radio wave in the detection target microwave band acquired from the detection target microwave reception intensity measurement unit 16 and the multiplied microwave (leakage radio wave) acquired from the multiplication microwave reception intensity measurement unit 26. Based on the intensity ratio, it may be determined whether or not to suppress the normal alarm. Specifically, assuming that the judgment formula is the reception intensity of the multiplied microwave / the reception strength of the detection target microwave, if the calculated value of the judgment formula is equal to or greater than a set threshold, it is determined that the normal alarm is suppressed. To do. As a result, even when the reception intensity of the original detection target microwave is small (the reception position is away from the transmission source, the intensity of the output radio wave is small, etc.) and the intensity of the multiplied microwave is accordingly small, It is possible to accurately discriminate whether or not the received microwave is from a false alarm source.

  Further, in each of the above-described embodiments and modifications, the reception system of the multiplied microwave is formed separately from the reception system of the fundamental wave (detection target microwave), but part or all of the reception system is common. It can also be converted. That is, although a specific circuit configuration is omitted in the above-described embodiment, this type of microwave band receiving unit can be configured with a superheterodyne receiving circuit. In this case, the reception bandwidth including the frequency of the detection target microwave (frequency band to be received) is secured by sweeping the output frequency of the local oscillator in the receiving circuit within a predetermined range. Usually, the local oscillator sweeps the frequency within the reception bandwidth only once in one operation time and repeats it. Therefore, the frequency range to be swept by the local oscillator is divided into two types, a first sweep frequency range in which the frequency band of the detection target microwave can be received and a second sweep frequency range in which the frequency band of the multiplied microwave can be received. Can be implemented by switching, while using the same antenna and receiving circuit, the period of sweeping at the first sweep frequency functions as the detection target microwave band receiving unit 12, and the second sweep frequency During the sweeping period, the multi-function microwave band receiver 22 functions. Therefore, the hardware components of the antenna and the receiving unit can be shared.

  In this case, either the detection target microwave or the multiplied microwave is output from the receiver, and which microwave is output is determined by the sweep frequency. The measurement unit can be shared.

  Further, as shown in FIG. 5, the microwave band receiving unit 12 'adopts a switching structure between a double superheterodyne method and a single superheterodyne method, so that the microwave band receiving unit is used together with the microwave band receiving unit. Subsequent hardware can be shared. That is, the microwave band receiving unit 12 ′ uses the first mixer 62 to frequency-mix the microwave captured by the antenna and the signal (oscillation frequency: 11.525 GHz) output from the first local oscillator 61. Is done. The detection target microwave is frequency-mixed by the first mixer 62 and output as a 1 GHz mixed signal. The multiplied microwave is frequency-mixed with the second harmonic signal (23.05 GHz) output from the first local oscillator 61 by the first mixer 62 and output as a mixed signal of 2 GHz. The intermediate frequency band amplifier 63 and the second mixer 64 are respectively arranged in the subsequent stage of the first mixer 62, and the second local oscillator 66 is connected to the second mixer 64 via the switch 65. ing. The oscillation frequency of the second local oscillator 66 is 900 MHz.

  As a result, when the switch 65 is turned off, frequency mixing is not performed in the second mixer 64, but the output of the intermediate frequency band amplifier 63 is directly output from the second mixer 64, and when the switch 65 is turned on, the second mixing is performed. The output signal of the intermediate frequency band amplifier 63 and the signal (oscillation frequency: 900 MHz) output from the second mixer 66 are frequency-mixed by the unit 64. Therefore, the detection target microwave outputs a 1 GHz signal as it is when the switch 65 is turned OFF. On the other hand, when the switch 65 is turned ON, the frequency-multiplied microwave is frequency-mixed by the second local oscillator 66 and output as a 1.1 GHz signal. Therefore, when a 900 MHz signal is output from the second local oscillator 66, the contact of the switch 65 switches between ON and OFF, and 1 GHz and 1.1 GHz are evaluated as the intermediate frequency (IF). It can be seen whether a signal based on a wave is output, and the reception intensity of both can be recognized. Therefore, hardware can be shared, and false alarms can be prevented at low cost.

  Furthermore, in each of the above-described embodiments, the determination is made based on the basic microwave and the multiplied microwave. However, it is of course possible to use a higher order harmonic of 3 times the microwave or higher. However, the higher the order, the weaker the reception intensity, so it is preferable to have a multiplied microwave.

12 Detection target microwave band reception unit 14 Detection target microwave reception frequency measurement unit 16 Detection target microwave reception intensity measurement unit 22 Multiplication microwave band reception unit 24 Multiplication microwave reception frequency measurement unit 26 Multiplication microwave reception intensity measurement unit 30 Analysis determination unit 42 Alarm display unit 44 Alarm sound output unit 52 Position detection unit 54 False alarm source position information storage unit

Claims (6)

In the microwave detector for controlling the alarm using the alarm means based on the detection of the predetermined microwave,
When the period during which the predetermined microwave is received is below the reference, the current position is stored as the malfunction source position,
A microwave detector having a function of suppressing notification of a normal alarm when a current position when a microwave is detected is within a reference distance from the stored false alarm source position. The period during which the predetermined microwave is received is the distance at which the predetermined microwave is detected,
The microwave detector according to claim 1, wherein the distance at which the predetermined microwave is detected is a distance emitted from the same transmission source obtained from a microwave reception history. The period during which the predetermined microwave is received is the distance at which the predetermined microwave is detected,
3. The microwave detector according to claim 1, wherein normal alarm notification is not suppressed when a distance at which the predetermined microwave is detected is 500 m or more. 4. The period during which the predetermined microwave is received is the distance at which the predetermined microwave is detected,
The microwave detector according to any one of claims 1 to 3, wherein the reference is set to 100 m or less. The period during which the predetermined microwave is received is the distance at which the predetermined microwave is detected,
The microwave detector according to any one of claims 1 to 3, wherein the reference is set to about several tens of meters. The program for making a computer implement | achieve the function in the microwave detector in any one of Claim 1 to 5.

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