JP2005339285A - Crime prevention system and portable crime prevention buzzer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To transmit to distant organizations concerned an emergency tone or alarm signal with a lower rate of false report based on an emergency sound or an emergency electric wave just by operating a switch of a portable crime prevention buzzer at hand without a victim or a witness going to an emergency button on a pole. <P>SOLUTION: The crime prevention system uses the portable crime prevention buzzer 1 which incorporates a sound-producing instrument and a radio transmitter and includes: a plurality of microphones 11 and antennas 14 installed outdoors with some intervals in between; a discriminator which discriminates the emergency tone from the portable crime prevention buzzer 1 among sounds collected by the respective microphones 11 and the emergency electric wave from the portable crime prevention buzzer 1 among electric waves picked up by the respective antennas 14, and issues an alarm signal; and an alarm apparatus for transmitting the alarm signals to the organizations concerned. The emergency tone discriminated by the discriminator should be confined to tremolo sound. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an outdoor crime prevention system and a portable crime prevention buzzer used therefor.

  In recent years, crimes such as snatching, extortion, slashing, kidnapping and abduction have been increasing rapidly outside school roads, busy alleys, and parks. Therefore, children and girls should carry a portable security buzzer, and when there is a crime, switch the portable crime prevention buzzer to emit an emergency sound to prevent or stop the crime or call for rescue. Is generally popular.

Also, depending on the area, security devices such as alarms and television cameras have been installed along the school route at a distance of, for example, 100 to 200 m. There are also patent applications for such crime prevention systems (Patent Documents 1 and 2). Currently, it is very difficult to constantly monitor multiple camera images at the same time, so it is common to install emergency buttons on alarms on street lights, poles, etc., and crime (including accidents) Victims and witnesses press the emergency button to inform the surveillance center or the like of the occurrence of crimes by wireless or wired, and related personnel such as surveillance personnel and police officers respond.
JP 2003-288654 A JP 2004-13317 A

  However, the emergency sound generated by the crime prevention buzzer can be heard loudly in the range of several tens of meters, and barely heard in the range of several hundreds of meters, and there is a problem that it is ineffective when there is no person in this range. Also, even if there is a person in this range, he / she will respond if the person is a member of the guard or police officer, but if the person is an ordinary person, he / she will respond to the fear of the recent worsening of crimes. In such a case, there is a possibility that it will not be lost.

  Moreover, in the crime prevention system by pressing the emergency button installed on the pole as described above, it is assumed that the victim or the witness of the crime goes to the location where the emergency button is installed. As described above, the emergency buttons are generally installed at a distance of 100 to 200 m. Therefore, if the crime scene happens to be close to the emergency button, you can go to the emergency button and press it, but if the crime scene is in the middle of the two emergency buttons next to each other, the victim or witness will not know the emergency button. However, even if it is understood, there is a problem that the emergency button cannot be reached due to the situation and time and there is a high possibility that it cannot be pressed.

  The object of the present invention is to solve the above-mentioned problems, and even if the victim or witness does not go to the emergency button of the pole, it is based on the emergency sound or the emergency radio wave from just by operating the portable buzzer buzzer at hand. Alarm signals with a low false alarm rate can be automatically sent to related organizations that are far away, and effective crime prevention can be achieved, and a commonly used portable crime prevention buzzer can be added as is or in part. It is to provide a crime prevention system that can be constructed easily and inexpensively. Another object of the present invention is to provide a portable crime prevention buzzer that can extremely reduce the false alarm rate by using the crime prevention system to distinguish between emergency sound and emergency radio waves.

In order to solve the above problems, the present invention employs the following means (1) to (4).
(1) A crime prevention system using a portable crime prevention buzzer incorporating a sound generator that emits an emergency sound by a switch operation, and a plurality of microphones installed outdoors at a distance from each other, and sounds picked up by the respective microphones And a warning device that determines that an emergency sound from a portable security buzzer is included, and a warning device that generates a warning signal when the determination device makes the determination and sends the warning signal to a related organization. Security system.

(2) A security system that uses a portable security buzzer that incorporates a sound generator that emits an emergency sound by switch operation and a wireless transmitter that emits an emergency radio wave by switch operation, and is installed outdoors at a distance from each other. A plurality of antennas, a discriminating device for discriminating that an emergency radio wave from the portable crime prevention buzzer is included in radio waves picked up by the respective antennas, and an alarm signal generated when the discrimination device makes the discrimination A security system comprising an alarm device for sending to an institution.

(3) A security system that uses a portable security buzzer that incorporates a sound generator that emits an emergency sound by switch operation and a wireless transmitter that emits an emergency radio wave by switch operation, and is installed outdoors at a distance from each other. It is determined that an emergency sound from a portable security buzzer is included in a sound picked up by a plurality of microphones and antennas, and an emergency from a portable security buzzer is included in a radio wave picked up by each antenna. A crime prevention system, comprising: a discrimination device that discriminates that radio waves are included; and an alarm device that generates an alarm signal and sends it to a related organization when the discrimination device makes the discrimination.

(4) A portable crime prevention buzzer incorporating a sound generator that emits an emergency sound by a switch operation and a wireless transmitter that emits an emergency radio wave by a switch operation.

[Emergency sound identification]
In the means (1) and (3), the location of the microphone is not particularly limited, but it is preferably installed on a pole such as a street light, a power pole, a security post, etc. standing outdoors. In places where there are no poles, it may be installed outside the house. The distance between microphones must be such that at least one microphone can pick up the emergency sound emitted by the portable security buzzer between two adjacent microphones at a distance from each other, preferably both This is the distance that the microphone can pick up. If the distance is the latter, it is possible to determine which microphone is closer to which emergency sound is generated by the portable security buzzer by comparing the sound pressure levels of emergency sounds picked up by both microphones.

  The emergency sound emitted by the sound generator of the portable security buzzer is not particularly limited. Emergency sounds generated by sound generators of commercially available portable security buzzers vary in frequency, presence / absence of frequency modulation, waveforms, and the like. For example, there are various frequencies in the range of about 2500 to 3500 Hz, and the frequency may fluctuate due to battery voltage drop. In addition, there are monotone sounds with a constant frequency, and there are sounds with trembling frequencies (such as tremolo sounds). As for the waveform, there is a sine wave, and there are a triangular wave and a complex waveform on which other frequencies are superimposed.

  On the other hand, general noises usually heard on roads are diverse, such as car horns, exhaust sounds, brake sounds, store broadcast sounds, and chimes. The microphone picks up the emergency sound simultaneously with these general noises (in a mixed state). Therefore, it is preferable that the determination device is configured to determine as accurately as possible that the emergency sound is included in the sound picked up by the microphone. If a general noise that is not a true emergency sound is erroneously determined as an emergency sound and an alarm signal is issued, it will be misreported, resulting in trouble in various areas.

  Therefore, the determination device is not limited to a specific configuration, but the configuration exemplified below is preferable so that the emergency sound can be determined as accurately as possible. Examples are shown separately.

(A) When discriminating almost all of various emergency sounds As a discrimination device, a waveform storage device that digitally stores various emergency sounds as registered sounds in advance, and an A / D that digitally converts and samples the sound picked up by the microphone Examples include a converter and a digital analyzer that compares the registered sound with the sampling sound and analyzes whether there is a match or an approximation with a predetermined tolerance. An example of the digital analyzer is a microcomputer using a CPU. If this tolerance is wide, false alarms are likely to be generated. Therefore, in order to reduce false alarms, the accuracy of A / D conversion is preferably as high as possible in order to narrow the tolerance, and the allowable difference is smaller (however, the true emergency sound) To the extent that it is not discerned and dropped)

  However, when the emergency sound and the emergency radio wave are discriminated in a double manner as in the means (3), even if the emergency sound is misjudged to some extent, the possibility of misreporting becomes extremely low by repeating the emergency radio wave discrimination. Therefore, the discrimination device can be simplified. For example, as a discrimination device, a device that discriminates that a sound picked up by a microphone includes a continuous sound of any frequency in a frequency range of various emergency sounds can be exemplified. More specifically, it is provided with a bandpass filter that passes only the frequency of 2500 to 3500 Hz and an analyzer that detects that there is a continuous sound that passes through the bandpass filter (this is an emergency sound). is there.

(B) When discriminating only to a specific emergency sound Among the various emergency sounds, the difference between general noise and the emergency sound that is difficult to distinguish from general noise is large because the difference from general noise is small There are emergency sounds that are easy to distinguish from general noises. For example, an emergency sound composed of a monotonous sound having a constant frequency of 2500 to 3500 Hz is difficult to distinguish from 2500 to 3500 Hz that exists in general noise. Therefore, by limiting to emergency sounds that are easy to determine, it is possible to determine with high accuracy and sensitivity, and prevent false alarms. Specifically, it is preferable that the determination is limited to an emergency sound of tremolo sound (so-called pyropyro sound, including a wobble tone) whose frequency periodically varies (in other words, frequency-modulated at a low frequency). Furthermore, it is preferable that the determination is limited to tremolo sounds whose fundamental frequency and modulation frequency (period of pyropyro) are in a specific range. The reason is that many of the commercially available mobile security buzzers emit tremolo sounds, while the general noises that are usually heard on the road rarely contain tremolo sounds. If limited, the configuration of the discriminating apparatus is simple.

  Giving specific ranges to the fundamental frequency and modulation frequency of tremolo sound corresponds to the fact that the frequency and modulation frequency of tremolo sound of commercial products are various and that the frequency fluctuates due to the voltage drop of the battery as described above. Because. If the power supply can be stabilized by the design of the portable crime prevention buzzer itself, the specific range can be narrowed, and it can be more reliably determined as general noise. The specific range of the fundamental frequency is preferably 1000 to 5000 Hz, and the specific range of the modulation frequency is preferably 1 to 10 Hz. The same range covers all tremolo sounds on the market. Moreover, if the specific range of the fundamental frequency is 2500 to 3500 Hz and the specific range of the modulation frequency is 2 to 5 Hz, it is possible to prevent false alarms while covering most of the tremolo sounds of commercial products. The frequency fluctuation width due to the modulation is not particularly limited, but 200 to 400 Hz can be exemplified (the frequency fluctuation width is, for example, 300 Hz, for example, if the fundamental frequency is 3040 Hz, the frequency fluctuation is 2890 to 3190 Hz). .)

  In this way, when discriminating only to the tremolo sound in a specific range, the discriminating device is an analyzer that analyzes that the sound picked up by the microphone includes the tremolo sound having the basic frequency and the modulation frequency in the specific range. It shall be provided. More specifically, an A / D converter that digitally converts and samples the sound picked up by the microphone, and a digital analyzer that digitally analyzes that the sampling sound includes the tremolo sound in the specific range. The thing provided can be illustrated. An example of the digital analyzer is a microcomputer using a CPU. In addition, it is preferable to provide a band-pass filter that passes only a specific range (for example, 1000 to 5000 Hz) of the fundamental frequency in front of the analyzer to remove or attenuate general noise of other frequencies in advance.

  As described above, when the emergency sound to be identified is limited to the tremolo sound (or other easily identifiable emergency sound), the emergency sound of the portable crime prevention buzzer will be changed to the tremolo sound (or other It is preferable to standardize to an emergency sound that is easy to distinguish.

[Emergency signal discrimination]
In the above means (2) and (3), the installation location of the antenna is not particularly limited, but it is preferably installed on a pole such as a street light, a power pole, a security post, etc. standing outdoors. In particular, the means (3) is more preferably installed on a pole together with the microphone. In places where there are no poles, it may be installed outside the house. The distance between the antennas must be such that at least one antenna can pick up emergency radio waves emitted by the wireless transmitter of the portable security buzzer between two adjacent antennas at a distance from each other. Preferably the distance that both antennas can pick up.

  The wireless transmitter incorporated in the portable crime prevention buzzer is not particularly limited, but a wireless transmitter using a wireless IC tag is preferable because it is small, light, and inexpensive. The emergency radio wave emitted by the wireless transmitter is not particularly limited, but an emergency radio wave having a frequency or type not generally used is preferable. Moreover, it is preferable that the emergency radio wave includes an identification (ID) signal for identifying an individual or a group carrying the portable security buzzer. This is because related organizations such as the monitoring center and the police can identify individuals or groups from the ID signals and quickly contact them.

  The switch of the wireless transmitter may share (a) the switch of the sound generator, (b) may provide a switch different from the switch of the sound generator, or (c) share the switch of the sound generator. However, another switch for operating only the wireless transmitter may be provided. In the case of sharing, since the radio transmitter and the sounder are operated simultaneously only by operating the shared switch, there is an advantage that the operation is simplest and easy to understand. In addition, it corresponds to the case where the case becomes louder if the sound generator emits an emergency sound depending on the situation of the situation by operating only the wireless transmitter with another switch of (b) and (c) and emitting only the emergency radio wave. Or in the case of kidnapping, abduction, etc.

The discriminating device is not limited to a specific configuration, but is equipped with a digital analyzer that digitally analyzes that radio waves picked up by an antenna include emergency radio waves from a portable security buzzer. It can be illustrated. An example of the digital analyzer is a microcomputer using a CPU.
The intensity of the emergency radio wave is preferably set so that it reaches a distance that is the same as or farther than the distance that the emergency sound of the portable crime prevention buzzer reaches.

  The alarm signal generated by the determination device is not particularly limited and may be any signal.

[About sending alarm signals]
The alarm signal generated by the alarm device is not particularly limited and may be any signal. However, it is preferable that the sound pressure level signal of the emergency sound of the portable crime prevention buzzer included in the sound picked up by the microphone is included. Analyzing the sound pressure level signal at related organizations such as the monitoring center and the police, and comparing the sound pressure level of the emergency sound from two adjacent microphones at a distance from each other, the mobile security buzzer sounds the emergency sound. This is because it is possible to determine which microphone is close to, preferably which point between the two microphones. The ID signal is preferably included.

  The means for sending the alarm signal is not particularly limited, and may be wireless or wired, and in the case of wired, any line such as a dedicated line for crime prevention, a telephone line, and a power line may be used. The “relevant organization” of the destination is not limited to a specific name, and broadly means an organization of a member in charge of a monitoring center, police, PTA, neighborhood association or other crime-related work or volunteer.

  According to the crime prevention system according to the present invention, even if the victim or witness does not go to the emergency button of the pole, only the switch operation of the portable buzzer buzzer at hand is performed, and the false alarm is generated based on the emergency sound or the emergency radio wave from there. A warning signal with a low rate can be automatically sent to related organizations away from it, so that crime prevention can be effectively implemented, and a commonly used portable crime prevention buzzer is used as it is or in part. By doing so, an excellent effect is achieved that it can be easily and inexpensively constructed. Moreover, according to the portable security buzzer according to the present invention, the false alarm rate can be extremely reduced by making the emergency sound and the emergency radio wave doubly discriminated using the security system.

  The crime prevention system is a crime prevention system that uses a portable crime prevention buzzer that incorporates a sound generator that emits an emergency sound when a switch is operated and a wireless transmitter that emits an emergency signal when the switch is operated. A plurality of microphones and antennas, and the sound picked up by each of the microphones determines that an emergency sound from a portable security buzzer is included, and the radio waves picked up by each of the antennas from the portable security buzzer A determination device that generates an alarm signal when it is determined that an emergency radio wave is included, and an alarm device that transmits the alarm signal to a related organization such as a monitoring center or the police. The emergency sound determined by the determination device may be limited to a tremolo sound whose frequency and modulation frequency are in a specific range. The specific range of the frequency may be 1000 to 5000 Hz, and the specific range of the modulation frequency may be 1 to 10 Hz.

  A crime prevention system according to a first embodiment embodying the present invention will be described with reference to FIGS. This crime prevention system includes a portable crime prevention buzzer 1 carried by a person and a fixed facility 10 installed on an outdoor pole P. 1 and 2, R is a road, P is a plurality of poles such as street lamps, telephone poles, security posts, etc. installed at a distance from each other along the road R, and H is a house is there.

[Mobile crime prevention buzzer 1]
As shown in FIG. 3, the portable security buzzer 1 includes a battery 2, a shared switch 3 that turns on / off power supply from the battery 2 to the sound generator 5 and the wireless transmitter 6, and only the wireless transmitter 6 from the battery 2. Sub switch 4 for turning on / off the power supply, sound generator 5 for generating emergency sound by power supply, wireless transmitter 6 for generating emergency radio wave by power supply, emergency for generating emergency signal and ID signal and placing them on emergency radio wave A signal / ID signal generator 7 is incorporated. The switches 3 and 4 may be operated in any manner such as a push button type, a rotary type, a slide type, and a stopper pull-out type.

  The sound generator 5 includes, for example, a sound signal generator 5a and a sound generator 5b that generates sound based on the sound signal. The emergency sound emitted by the sound generator 5 is a tremolo sound having a fundamental frequency in the range of 2500 to 3500 Hz and a modulation frequency in the range of 2 to 5 Hz. 4A schematically shows a fundamental frequency before frequency modulation, FIG. 4B schematically shows a modulation frequency, and FIG. 4C schematically shows a tremolo sound after frequency modulation.

  The wireless transmitter 6 includes, for example, a wireless IC tag 6a and an antenna 6b for extending the reach of the wireless radio wave. The wireless transmitter 6 using a wireless IC tag that has become popular in recent years can be easily formed into the portable security buzzer 1 because it can be formed in an ultra-compact, ultra-light, and low price, and does not impair the portability of the portable security buzzer 1. There is almost no rise. Therefore, there is an advantage that wide spread can be expected. As the emergency signal / ID signal generator 7, for example, a small microcomputer chip (PIC) can be used. The ID signal identifies an individual or a group. Although an example of an emergency signal and an ID signal is displayed in FIG. 5, actually, an ASCII code or the like is used and is based on a general communication procedure manual.

  Therefore, the emergency radio wave emitted from the wireless transmitter 6 includes an emergency signal and an ID signal. The emergency signal and the ID signal may be alternately emitted at a constant time interval, or may be simultaneously emitted after being superimposed. Further, by intermittently emitting emergency radio waves at regular time intervals (for example, every few seconds), the degree of wear of the battery 2 can be reduced (intermittent discharge), for example, several hundreds of commercially available alkaline batteries (AA) Intermittent transmission of time is possible.

[Fixed equipment 10]
The fixed equipment 10 is installed on each of the plurality of poles P, and as shown in FIG.
・ Two microphones 11 with moderate directivity directed in both directions on the road
An amplifier 12 that amplifies the sound (sound signal) picked up by the microphone 11
A band-pass filter 13 that passes only a specific frequency range (for example, 2500 to 3500 Hz) in the sound (sound signal) amplified by the amplifier 12 and removes or attenuates general noise of other frequencies before the next analysis.
One antenna 14
A radio receiver 15 that receives radio waves picked up by the antenna 14
Of the radio waves received by the wireless receiver 15, it is determined that the sound that has passed through the band pass filter 13 includes the tremolo sound of the specific range from the sound generator 5 of the portable security buzzer 1. , A discrimination device 16 for discriminating that an emergency radio wave from the wireless transmitter 4 of the portable security buzzer 1 is included.
An alarm device 17 that generates an alarm signal when the determination device 16 makes the determination and sends it to a related organization such as a monitoring center or police.

  Here, an active filter is preferably used as the bandpass filter 13. The discriminating device 16 includes an A / D converter that digitally converts and samples the sound that has passed through the band-pass filter 13, and digital analysis that digitally analyzes that the sampling sound includes the tremolo sound in the specific range. The thing provided with the vessel can be illustrated. An example of the digital analyzer is a microcomputer using a CPU.

  The alarm device 17 is configured to send the generated alarm signal to the related organization wirelessly or by wire. The specific configuration of the alarm device 17 is not particularly limited, and examples include an alarm signal generator and a radio transmitter in the case of radio. In addition, a sound pressure level signal of an emergency sound of the portable security buzzer 1 included in the sound picked up by the microphone 11 is added to the alarm signal. In FIG. 2, the sound pressure level of the emergency sound that is emitted from the portable security buzzer 1 and reaches the two adjacent microphones 11 at a distance from each other is schematically represented by the thickness of the arrow. For this reason, by analyzing the sound pressure level signal in the related organizations and comparing the sound pressure level of the emergency sound from the two microphones 11, the portable security buzzer 1 emits the emergency sound to any microphone 11. It is possible to determine which point is closer or preferably between the two microphones 11.

  Further, the ID signal from the portable crime prevention buzzer 1 is also added to the alarm signal. For this reason, it is possible to identify a person or a group from the ID signal at a related organization and quickly contact them.

  The pole P is also provided with the above-described conventional crime prevention system, wherein 21 is an emergency button of an alarm device, 22 is a television camera, and 23 is a speaker. When it is determined that the sound picked up by the microphone 11 includes the emergency sound of the portable security buzzer 1, for example, a larger emergency sound can be emitted from the speaker 23.

  According to the crime prevention system of the present embodiment configured as described above, even if the victim or witness does not go to the emergency button 21 of the pole P, only the common switch 3 of the portable security buzzer 1 at hand is turned on. Thus, an alarm signal with a very low false alarm rate can be automatically sent to a remote related organization based on the double discrimination of the emergency sound and emergency radio wave from the buzzer 1, and thus crime prevention can be effectively implemented. Moreover, it can be easily and inexpensively constructed by using the portable crime prevention buzzer 1 that is generally popular.

  When a wireless transmitter is used in combination, it can be completely separated from general noise, and a more accurate emergency signal can be detected. Moreover, since the reach of the emergency radio wave is longer than that of the emergency sound, a wide range of monitoring can be performed. Furthermore, the sender can be identified easily by sending the radio signal transmission contents including the emergency signal and the ID signal. In addition, if an emergency sound is further increased depending on the contents of the incident / accident, etc., the incident can be further increased by turning on the sub switch 4 and using the radio wave alone. In the case of kidnapping and abduction, it can also be used to confirm whereabouts.

  The present invention is not limited to the above-described embodiments, and can be modified and embodied as appropriate without departing from the spirit of the invention.

It is a front view which shows the crime prevention system of Example 1 which concerns on this invention. It is a top view of the crime prevention system. It is a block diagram which shows the structure of the portable crime prevention buzzer in the crime prevention system. It is a wave form diagram showing roughly the emergency sound of the portable security buzzer. It is explanatory drawing which shows the emergency signal and ID signal of the portable crime prevention buzzer. It is a block diagram which shows the structure of the fixed installation in the crime prevention system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mobile security buzzer 2 Battery 3 Shared switch 4 Sub switch 4 Wireless transmitter 5 Sound generator 6 Wireless transmitter 10 Fixed equipment 11 Microphone 12 Amplifier 13 Band pass filter 14 Antenna 15 Wireless receiver 16 Discriminating device 17 Alarm device P Paul

Claims (12)

  A security system that uses a portable security buzzer that incorporates a sound generator that emits an emergency sound by switch operation, and includes a plurality of microphones installed outdoors at a distance from each other, and a sound picked up by each of the microphones. A crime prevention system, comprising: a discrimination device that discriminates that an emergency sound from a portable crime prevention buzzer is included; and an alarm device that generates an alarm signal and sends it to a related organization when the discrimination device makes the discrimination.   A security system that uses a portable security buzzer that incorporates a sound generator that emits an emergency sound by switch operation and a wireless transmitter that emits an emergency radio wave by switch operation, and has multiple antennas installed outdoors at a distance from each other A discriminating device for discriminating that an emergency radio wave from the portable crime prevention buzzer is included in the radio waves picked up by the antennas, and generating a warning signal when the discrimination device makes the discrimination and sending it to a related organization A security system comprising an alarm device.   A security system that uses a portable security buzzer that incorporates a sound generator that emits an emergency sound by switch operation and a wireless transmitter that emits an emergency radio wave by switch operation, and a plurality of microphones installed outdoors at a distance from each other And the antenna and the sound picked up by each of the microphones determines that the emergency sound from the portable security buzzer is included, and the radio waves picked up by the respective antennas include the emergency radio wave from the portable security buzzer A crime prevention system, comprising: a discrimination device that discriminates that the alarm is detected; and an alarm device that generates an alarm signal and sends it to a related organization when the discrimination device makes the discrimination.   The crime prevention system according to claim 1 or 3, wherein the microphone is installed on a pole such as a street light, a power pole, and a crime prevention column that is erected outdoors.   The crime prevention system according to claim 1 or 3, wherein the emergency sound is a tremolo sound having a fundamental frequency in a specific range of 1000 to 5000 Hz and a modulation frequency in a specific range of 1 to 10 Hz.   The crime prevention system according to claim 5, wherein the discrimination device includes a digital analyzer that analyzes that the tremolo sound is included in the sound picked up by the microphone.   The crime prevention system according to claim 6, wherein a band-pass filter that passes only a specific range of the fundamental frequency is provided in front of the analyzer.   The crime prevention system according to claim 1 or 3, wherein a sound pressure level signal of the emergency sound included in a sound picked up by the microphone is added to the alarm signal.   The crime prevention system according to claim 2 or 3, wherein the antenna is installed on a pole such as a street light, a utility pole, a crime prevention column, etc., standing outdoors.   The crime prevention system according to claim 2 or 3, wherein the wireless transmitter uses a wireless IC tag.   The crime prevention system according to claim 2 or 3, wherein an identification (ID) signal for identifying an individual or a group is added to an emergency radio wave emitted by the wireless transmitter.   A portable security buzzer that incorporates a sound generator that emits an emergency sound when operated by a switch and a wireless transmitter that generates emergency radio waves when operated by a switch.

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