JP2010170398A - Disaster emergency notification system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive and highly reliable disaster emergency notification system. <P>SOLUTION: This disaster emergency notification system includes a broadcasting base station 2 for transmitting a notification signal including disaster information by using an AM radio broadcast wave, and the broadcasting base station 2 transmits a notification signal by using a low frequency band within the range of 20-50 Hz and a high frequency band within the range of 10-20 kHz out of the modulation frequency bands authorized as AM radio broadcast wave. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a disaster emergency notification system using AM radio broadcast waves.

  Since disaster information such as earthquakes and tsunamis can be received from disaster systems operated by ministries and local governments, a system is provided that distributes disaster information to the public by e-mail when a disaster occurs. (For example, see Patent Documents 1 and 2). According to electronic mail, information can be distributed to a large number of people at a low cost, so that a system for reporting the occurrence of a disaster can be easily introduced.

JP 2003-132473 A JP 2006-31470 A

  However, in actuality, when disaster information is to be transmitted by e-mail when a disaster occurs, the mail server may be congested due to simultaneous transmission to a large number of people, and mail arrival may be delayed. In addition, in the case of using e-mail, it is necessary to register an e-mail address in advance to the information sender, so that the number of people who are notified of disaster information is limited. Therefore, a system using a communication infrastructure such as e-mail is not sufficient when it is necessary to immediately and reliably transmit information to as many people as possible when a disaster occurs.

  Therefore, an object of the present invention is to provide a disaster emergency notification system with low cost and high reliability.

  The present invention has been made in view of the above circumstances, and a disaster emergency notification system according to the present invention includes a broadcast base station that transmits a notification signal including disaster information using an AM radio broadcast wave, and the broadcast base station Is characterized in that the notification signal is transmitted using a low frequency band within a range of 20 Hz to 50 Hz or a high frequency band within a range of 10 kHz to 20 kHz among modulation frequency bands recognized as AM radio broadcast waves. To do.

  According to the said structure, since AM radio broadcast wave is used for communication infrastructure, congestion does not arise, but disaster information can be transmitted to many receivers immediately and reliably. Furthermore, when communicating by AM radio broadcast waves, there is no need for address registration work such as e-mail, so the number of people who can report disaster information can be easily expanded. Further, the AM radio broadcast wave has a feature that the reach distance from the broadcast base station is long, and therefore has an advantage that it is suitable for reporting disaster information over a wide area. In addition, since AM radio broadcasting can use existing infrastructure, the introduction cost can be reduced.

  In addition, the low frequency band 20 Hz to 50 Hz or the high frequency band 10 kHz to 20 kHz of the modulation frequency band recognized as the AM radio broadcast wave is a band having a characteristic that the AM radio receiver is difficult to reproduce as sound. Therefore, even if the notification signal is transmitted using the AM radio broadcast wave, the program sound of the existing AM radio broadcast is not hindered. Therefore, it is possible to carry out disaster notification without interrupting normal program broadcasting. This is very effective when the frequency of reporting is increased by increasing the types of disasters that the system supports.

  When the notification signal is transmitted using a low frequency band within the range of 20 Hz to 50 Hz, the broadcast base station includes an audio signal output means for outputting an audio signal including program audio information, and the audio signal A low-frequency cut filter that cuts the low-frequency band from the audio signal output by the generation unit; and a notification signal superimposing unit that superimposes the notification signal on the audio signal output from the low-frequency cut filter. You may do it.

  According to the said structure, the audio | voice signal of a normal AM radio broadcast program and the report signal containing disaster information can be easily and reliably superimposed on an AM radio broadcast wave in a state where the frequency band is divided.

  When transmitting the notification signal using a high frequency band within the range of 10 kHz to 20 kHz, the broadcast base station outputs an audio signal output means for outputting an audio signal including program audio information, and the audio signal A high-frequency cut filter that cuts the high-frequency band from the audio signal output by the generation unit; and a notification signal superimposing unit that superimposes the notification signal on the audio signal output from the high-frequency cut filter. You may do it.

  According to the above configuration, as in the case of using the low frequency band, an AM radio broadcast wave can be easily converted into a frequency signal for an audio signal of a normal AM radio broadcast program and a notification signal including disaster information. And it can be made to superimpose reliably.

  The notification signal may include a disaster type code indicating the type of disaster that has occurred.

  According to the configuration, the receiver can generate an appropriate alarm according to the disaster type code included in the received notification signal.

  The notification signal may include a region code indicating a region requiring notification.

  According to the said structure, the receiver can generate an alarm according to the area code contained in the received notification signal.

  The receiver further includes a receiver that generates an alarm according to the content of the notification signal when receiving the notification signal transmitted from the broadcast base station using an AM radio broadcast wave, and the receiver is located in an area where it is located. A storage unit that stores region information indicating the region, a collation unit that collates the region information stored in the storage unit with the region code included in the notification signal, and a region indicated by the region code in the collation unit An alarm generation unit may be provided that generates an alarm when the area matches the area indicated by the area information.

  According to the above configuration, the receiver generates an alarm in response to only the disaster information related to the area where the receiver is located, so that no unnecessary alarms are generated and unnecessary user confusion can be prevented.

  The receiver has a GPS unit capable of detecting a self-location using GPS, and the storage unit is configured to store a region to which the self-location detected by the GPS unit belongs as the region information. May be.

  According to the said structure, even if it is a case where the user with a receiver moves, the appropriate alarm corresponding to the location area of the receiver at the time of disaster occurrence can be generated.

  When the receiver receives the notification signal, the receiver may transmit a disaster countermeasure command to an external device according to the content of the notification signal.

  According to the above configuration, the receiver that has received the notification signal automatically transmits a disaster countermeasure command to an external device (for example, a core server, a device in a factory, a land drive device, a gas cooker, etc.) Damage can be prevented immediately.

  The disaster emergency notification receiver of the present invention receives an AM radio broadcast wave, and within a modulation frequency band recognized as an AM radio broadcast wave, a low frequency band within a range of 20 Hz to 50 Hz or within a range of 10 kHz to 20 kHz. A high frequency band signal is extracted, and an alarm is generated according to the content of the signal.

  According to the above-described configuration, as described above, it is possible to receive disaster information immediately and surely at a low cost, and to notify the occurrence of a disaster without obstructing the program sound of the existing AM radio broadcast.

  As is clear from the above description, according to the present invention, it is possible to provide a disaster emergency notification system with low cost and high reliability.

1 is an overall view of a disaster emergency notification system according to an embodiment of the present invention. It is drawing explaining the frequency band of the report signal in the disaster emergency notification system shown in FIG. It is drawing explaining the encoding principle of the report signal shown in FIG. It is drawing explaining the encoding principle of the report signal of a 1st modification. It is drawing explaining the encoding principle of the report signal of a 2nd modification. It is drawing explaining the format of the report signal shown in FIG. It is a block diagram explaining the structure of the portable receiver used for the disaster emergency notification system shown in FIG. It is a block diagram explaining the structure of the stationary receiver used for the disaster emergency notification system shown in FIG.

  Embodiments according to the present invention will be described below with reference to the drawings.

  FIG. 1 is an overall view of a disaster emergency notification system 1 according to an embodiment of the present invention. As shown in FIG. 1, the disaster emergency notification system 1 includes a broadcast base station 2 that performs AM radio broadcasting. The broadcasting base station 2 performs a performance place 3 (audio signal output means) that generates an audio signal including program audio information for normal radio broadcasting, and modulates the audio signal generated at the performance place 3 using an amplitude modulation method. And a transmitting station 5 for transmitting to an unspecified number of publics by AM radio broadcast waves (medium waves).

  Furthermore, the broadcast base station 2 of the present invention includes a low-frequency cut filter 4 and a notification information superimposing device 7 (report signal superimposing means). The low frequency cut filter 4 is provided between the performance place 3 and the transmission place 5 and can cut a signal in a low frequency band (20 Hz to 50 Hz) in the audio signal generated at the performance place 3. The notification information superimposing device 7 can turn on / off the operation of the low-frequency cut filter 4, and from the ministry 6 or the like with respect to the cut low frequency band of the audio signal output from the active low-frequency cut filter 4. The notification signal including the received disaster information is superimposed.

  The disaster emergency notification system 1 includes a portable receiver 9 and a stationary receiver 10 for receiving a notification signal transmitted from the broadcast base station 2 using a medium wave. The portable receiver 9 is a small, thin and light device (for example, a card-type device) formed as an IC chip. The receivers 9 and 10 are dedicated terminal devices for emergency disaster notification, but may be incorporated in other devices (for example, mobile phones and radio terminals). The portable receiver 9 is possessed by general citizens, employees such as fire departments and government offices, hospitals, nursing facilities, schools, and the like. The stationary receiver 10 is installed in a residence, an organization having a disaster prevention system (for example, a fire department or a public office), a ship, a port facility, and the like.

  FIG. 2 is a diagram for explaining the frequency band of a notification signal in the disaster emergency notification system 1 shown in FIG. Note that the horizontal axis of FIG. 2 is logarithmically expressed by the modulation frequency of the AM radio broadcast wave, and the vertical axis represents the reproduction audio level of a normal AM radio receiver and the transmission audio level of the transmitting station 5. As shown in FIG. 2, the modulation frequency recognized as an AM radio broadcast wave is approximately 20 Hz to 20 kHz, and the transmitting station 5 transmits radio waves for program broadcast within the frequency range. In addition, the frequency range that a normal AM radio receiver can reproduce is approximately 20 Hz to 12 kHz, and this frequency range is an audible band of a human being who is a listener. In the audible band, 20 to 100 Hz, the sound level decreases as the modulation frequency decreases. In the audible band, 9 to 12 kHz, the sound level decreases as the modulation frequency increases.

  The broadcast base station 2 of the present invention transmits a report signal using a low frequency band within a range of 20 Hz to 50 Hz or a high frequency band within a range of 10 kHz to 20 kHz as a report band among frequency bands having a low audio level. It is configured as follows. This numerical range is that the frequency band of the low frequency band is less than 20 Hz, which is outside the frequency characteristics of the transmitting station 5, while if it exceeds 50 Hz, the report signal is mixed with the program audio in a normal AM radio receiver. This is because there is a high possibility that interference will occur in the program, and if the high frequency band is less than 10 kHz, the program signal can be heard by mixing the program signal with the program audio in a normal AM radio receiver. This is because, if the frequency exceeds 20 kHz, the frequency characteristic of the transmitting station 5 is not satisfied.

  In FIG. 1, the low-frequency cut filter 4 is illustrated assuming that a low-frequency band within a range of 20 Hz to 50 Hz is used as a notification band. However, a high-frequency band within a range of 10 kHz to 20 kHz is illustrated as a notification band. When using as a high frequency cut filter that can cut a signal in a high frequency band (10 kHz to 20 kHz) in the audio signal generated at the performance place 3 instead of the low frequency cut filter 4, the notification information The superimposing device 7 may superimpose the notification signal on the cut high frequency band of the audio signal output from the active high frequency cut filter.

  FIG. 3 is a diagram for explaining the encoding principle of the notification signal shown in FIG. As shown in FIG. 3, a base waveform using a specific frequency (for example, 50 Hz) in the notification band is set to “0”, and the phase is delayed by a predetermined angle (for example, 90 °) at the same frequency from the base waveform. The delay waveform is denoted by “1”. The report information superimposing device 7 (see FIG. 1) generates a synthesized wave that is phase-modulated by superimposing a delay waveform on the base waveform as a report signal. Since this synthesized wave is the same as that obtained by applying an effect to the sound of the specific frequency, it can be easily realized within the scope of broadcasting regulations.

  Note that encoding of a communication signal is not limited to the above principle, and may be performed using a principle such as the following modification, for example. FIG. 4 is a diagram for explaining the encoding principle of the notification signal of the first modification. As shown in FIG. 4, encoding of a communication signal is performed by setting a waveform in which a specific frequency (for example, 30 Hz) continues for a first time (for example, 0.1 second) as a sign “0”, and the same frequency is paused. A waveform that lasts for a second time (for example, 0.3 seconds) with the symbol “1” interposed therebetween may be set to “1”. FIG. 5 is a diagram for explaining the encoding principle of the notification signal of the second modification. As shown in FIG. 5, the encoding of the communication signal is performed by setting a base waveform using a specific frequency (for example, 30 Hz) as a code “0” and an additional waveform having a frequency (for example, 50 Hz) different from the base waveform. A waveform in which is superimposed may be represented by “1”. 3 to 5 exemplify 30 Hz and / or 50 Hz as the frequency used when the low frequency band is the notification band, but when the high frequency band is the notification band, for example, 10 kHz and / or 12 kHz may be used.

  FIG. 6 is a diagram for explaining the format of the notification signal shown in FIG. As shown in FIG. 6, the notification signal transmitted from the broadcast base station 2 has areas of a synchronization code, an area code, a disaster type code, a reserve code, and a checksum. The synchronization code is set for the receivers 9 and 10 to recognize that the reception of the notification signal has started. As the region code, a code corresponding to a region requiring an emergency call out of a plurality of regions divided in advance is set. For example, when a tsunami occurs, a code corresponding to a coastal region is set as the region code. As the disaster type code, a code corresponding to the type of disaster (for example, earthquake, tsunami, flood, lightning, etc.) indicated by the disaster information received from the ministry 6 or the like is set. The spare code is a spare code for coping with future expansion of transmission information such as division of report areas and subdivision of disaster types. The checksum is a code used for error detection.

  FIG. 7 is a block diagram illustrating the configuration of the portable receiver 9 used in the disaster emergency notification system 1 shown in FIG. As shown in FIG. 7, the portable receiver 9 includes a reception antenna 11, a low-pass filter 12, a demodulation unit 13, a GPS unit 14, a storage unit 15, a verification unit 16, a disaster information determination unit 17, and an alarm generation unit 18. And a power source 19. The low-pass filter 12 extracts only the low frequency band (20 Hz to 50 Hz) from the medium wave received by the receiving antenna 11. In FIG. 7, the low-pass filter 12 is illustrated on the assumption that a low-frequency band within a range of 20 Hz to 50 Hz is used as a notification band. However, a high-frequency band within a range of 10 kHz to 20 kHz is illustrated as a notification band. When using as, instead of the low-pass filter 12, a high-pass filter that extracts only a high frequency band (10 kHz to 20 kHz) from the medium wave received by the receiving antenna 11 may be used.

  The demodulator 13 demodulates the report signal included in the low frequency band extracted by the low pass filter 12 (when using a high frequency band within a range of 10 kHz to 20 kHz as the report band, the high pass Demodulate the notification signal included in the high frequency band extracted by the filter). The GPS unit 14 detects its own position (the position of the receiver 9) using GPS (Global Positioning System). The storage unit 15 stores the region to which the latest self-location detected by the GPS unit 14 belongs, the relationship between the disaster type code and the disaster type, and the like. The collation unit 16 collates the area information stored in the storage unit 15 with the area code included in the received notification signal.

  The disaster information determination unit 17 determines the type of disaster that occurred from the disaster type code included in the received notification signal. The alarm generation unit 18 uses the alarm (18) related to the type of disaster determined by the disaster information determination unit 17 when the region indicated by the region code in the notification signal matches the region indicated by the region information in the storage unit 15 in the verification unit 16. Warning sound, warning display, warning lamp, etc.). Further, the portable receiver 9 normally stands by in a standby state in which a standby current is passed, and when receiving a notification signal, the alarm generation function is turned on to generate an alarm. That is, the disaster emergency notification system 1 is a push type information distribution system.

  FIG. 8 is a block diagram illustrating the configuration of a stationary receiver 10 used in the disaster emergency notification system 1 shown in FIG. As shown in FIG. 8, the stationary receiver 10 includes a reception antenna 11, a low-pass filter 12, a demodulation unit 13, a storage unit 25, a verification unit 16, a disaster information determination unit 17, an alarm generation unit 28, and countermeasure command transmission. Unit 29, transmission antenna 30, power source 19 and the like. Note that the receiving antenna 11, the low-pass filter 12, the demodulating unit 13, the collating unit 16, the disaster information determining unit 17, and the power source 19 have the same functions as those of the portable receiver 9, and thus detailed description thereof is omitted. .

  The storage unit 25 stores in advance the area to which the receiver 10 is located, the relationship between the disaster type code and the disaster type, and the like. The alarm generation unit 28 uses the alarm (28) for the type of disaster determined by the disaster information determination unit 17 when the region indicated by the region code in the notification signal matches the region indicated by the region information in the storage unit 25 in the verification unit 16. A warning sound, a warning display, a warning lamp, a red light, etc.), and a disaster countermeasure command corresponding to the disaster type determined by the disaster information determination unit 17 is transmitted to the countermeasure command transmission unit 29. The countermeasure command transmission unit 29 wirelessly transmits a countermeasure command signal corresponding to the disaster type from the transmission antenna 30 to the external devices 31 to 34. The countermeasure command transmission unit 29 may transmit a countermeasure command signal corresponding to the disaster type to the external devices 31 to 34 by wire. In addition, the devices 31 to 34 are provided with means for receiving a countermeasure command signal and means for controlling its own operation in accordance with the received signal.

  For example, when the disaster type is earthquake, the countermeasure command transmission unit 29 transmits an earthquake countermeasure command signal, and secondary damage such as the backbone server 31, the in-factory device 32, and the gas cooker 34 that receives the earthquake countermeasure command signal is assumed. The device to be operated automatically performs countermeasure control such as stopping the operation. When the disaster type is a tsunami, the countermeasure command transmitter 29 transmits a tsunami countermeasure command signal, and the land drive device 33 that receives the signal performs control to automatically close the land anchor.

  According to the configuration described above, since the medium wave of AM radio broadcasting is used for the communication infrastructure, congestion does not occur, and disaster information is immediately and reliably transmitted to a large number of receivers 9 and 10. be able to. Furthermore, in the case of communication using medium waves, since there is no need for address registration work such as e-mail, it is possible to easily increase the number of people who are notified of disaster information. Further, since the medium wave has a feature that the reach distance from the broadcast base station 2 is long, there is an advantage that it is suitable for reporting disaster occurrence information over a wide area. Moreover, since the medium wave can use the infrastructure of the existing AM radio broadcasting station, the introduction cost can be suppressed.

  In addition, the low frequency band 20 Hz to 50 Hz or the high frequency band 10 kHz to 20 kHz of the modulation frequency band recognized as the AM radio broadcast wave is a band having a characteristic that the AM radio receiver is difficult to reproduce as sound. Therefore, even if the notification signal is transmitted using the AM radio broadcast wave, the program sound of the existing AM radio broadcast is not hindered. Therefore, it is possible to carry out disaster notification without interrupting normal program broadcasting. This is very effective when the frequency of reporting is increased by increasing the types of disasters that the system supports.

  In addition, since the receivers 9 and 10 generate alarms only in response to disaster information related to the area where the receivers 9 and 10 are located, no unnecessary alarms are generated and unnecessary user confusion can be prevented. Furthermore, since the portable receiver 9 sequentially updates the self-location stored in the storage unit 15 using GPS, even if the user who owns the portable receiver 9 moves, An appropriate alarm corresponding to the location of the portable receiver 9 at the time of occurrence can be generated. Further, when the stationary receiver 10 receives the notification signal, the stationary receiver 10 sends it to an external device (for example, the backbone server 31, the in-factory device 32, the land drive device 33, the gas cooker 34, etc.) according to the content of the signal. Since the disaster countermeasure command is automatically transmitted, it is possible to prevent the occurrence of damage and the spread of damage.

1 Disaster emergency call system 2 Broadcasting base station 3 Performance place (audio signal output means)
4 Low cut filter (or high cut filter)
7 Report information superimposing device (report information superimposing means)
9,10 Receiver 12 Low-pass filter (or high-pass filter)
14 GPS unit 15 storage unit 16 collation unit 17 disaster information determination unit 18, 28 alarm generation unit 25 storage unit 29 countermeasure command transmission unit

Claims (9)

It has a broadcast base station that transmits a report signal including disaster information using AM radio broadcast waves
The broadcast base station transmits the notification signal using a low frequency band within a range of 20 Hz to 50 Hz or a high frequency band within a range of 10 kHz to 20 kHz among modulation frequency bands recognized as AM radio broadcast waves. Disaster emergency call system characterized by that. The broadcast base station is
Audio signal output means for outputting an audio signal including program audio information;
A low frequency cut filter that cuts the low frequency band from the audio signal output by the audio signal generating means;
Report signal superimposing means for superimposing the report signal on the audio signal output from the low-frequency cut filter;
The disaster emergency notification system according to claim 1, comprising: The broadcast base station is
Audio signal output means for outputting an audio signal including program audio information;
A high frequency cut filter for cutting the high frequency band from the audio signal output by the audio signal generating means;
Report signal superimposing means for superimposing the report signal on the audio signal output from the high-frequency cut filter;
The disaster emergency notification system according to claim 1, comprising:   4. The disaster emergency notification system according to claim 1, wherein the notification signal includes a disaster type code indicating a type of disaster that has occurred.   The disaster emergency notification system according to any one of claims 1 to 4, wherein the notification signal includes a region code indicating a region requiring notification. A receiver that generates an alarm according to the content of the notification signal when receiving the notification signal transmitted from the broadcast base station using an AM radio broadcast wave;
The receiver has a storage unit that stores region information indicating a region in which the receiver is located, a collation unit that collates the region information stored in the storage unit with the region code included in the notification signal, The disaster emergency notification system according to claim 5, further comprising: an alarm generation unit that generates an alarm when the region indicated by the region code matches the region indicated by the region information. The receiver has a GPS unit capable of detecting its own position using GPS,
The disaster emergency notification system according to claim 6, wherein the storage unit is configured to store, as the region information, a region to which the self-location detected by the GPS unit belongs.   The disaster emergency notification system according to any one of claims 5 to 7, wherein, when the receiver receives the notification signal, the receiver transmits a countermeasure command signal to an external device according to the content of the notification signal.   An AM radio broadcast wave is received, and a signal in a low frequency band within a range of 20 Hz to 50 Hz or a high frequency band within a range of 10 kHz to 20 kHz is extracted from a modulation frequency band recognized as an AM radio broadcast wave, and the signal is extracted. A receiver for disaster emergency notification, characterized by generating an alarm according to the content of

Images