JP2000068954A - Broad band multiple address radio system and method for preventing illegal public address sound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a broad band multiple address radio system and the illegal public address sound prevention method where it is prevented that a receiver with a loudspeaker receives illegal communication and makes public addressing. SOLUTION: A digitally coded voice signal 1 and a mute release signal 2 are inputted to an encryption device 3. The encryption device 3 uses the inputted signal to encrypt by using an encryption key 4 and outputs it to a transmitter 5. The transmitter 5 applies radio transmission processing to the inputted digital signal. A receiver 6 of a reception device 20 receives the signal propagated through a radio channel and demodulates the signal. A decoder 7 receives the demodulated signal. The decoder 7 uses a decode key 8 to apply decode processing to the received and encrypted signal. The decoded voice signal is inputted to a loudspeaker 9. The loudspeaker 9 makes public addressing of the inputted voice signal when a mute release device 10 decodes correctly the signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a wide-area broadcast radio system and a method for preventing illegal voice propagation in wide-area broadcast radio in the field of digital radio communication.

[0002]

2. Description of the Related Art Conventionally, a wide-area broadcast radio system of this type and a method for preventing unauthorized loudspeakers have been proposed by using a tone signal or M signal.
There is known a method of using the SK signal for canceling the sound mute. Further, in the method using the MSK signal, a method is known in which time information is used as an MSK signal for canceling the loudspeaker mute.

[0003]

However, in the above-described conventional method for preventing unauthorized voice-raising, it is easy to intercept the signal for canceling the voice-loud mute and to pray the signal, and to record / play back or generate a false signal to easily perform unauthorized communication. This makes it possible to perform loudspeaker.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems. By encrypting a loudspeaker mute release signal and a telephone call, a correct loudspeaker mute release signal and a loudspeaker are required if they are not legal. It is an object of the present invention to provide a wide-area broadcast radio system and a method for preventing an illegal loudspeaker voice, which make it impossible to generate a vocal sound, and which cannot perform a loudspeaker operation unless a correct loudspeaker mute release signal and a loudspeaker voice are used.

[0005]

The present invention adopts the following constitution in order to solve the above problems.

In order to solve the above problem, the present invention provides a transmitting apparatus including a predetermined mode encryption device using secret key information, a receiving loudspeaker including a predetermined mode decryption device and using secret information. are doing.

[0007] With this configuration, a correct loudspeaker mute release signal and a loudspeaker cannot be created unless a proper transmitter is used, and a loudspeaker operation cannot be performed unless a correct loudspeaker mute release signal and loudspeaker are used. Therefore, loudspeaker broadcasting due to unauthorized communication is prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention relating to a wide area broadcast radio system according to the first aspect of the present invention is directed to a transmitting apparatus having an encryption device of a predetermined mode using secret key information in a predetermined communication;
And a receiving loudspeaker provided with a decoding device in a predetermined mode, which prevents loudspeaker broadcasting by illegal communication using secret information.

[0009] With this configuration, a correct loudspeaker mute release signal and loudspeaker cannot be generated unless the transmitting device uses mutually proper secret key information, and the loudspeaker must not be a correct loudspeaker mute release signal and loudspeaker by the correct receiving loudspeaker. Loudspeaking operation cannot be performed. Therefore, loudspeaker broadcasting due to unauthorized communication is prevented.

In the second aspect of the present invention, the communication of the wide area broadcast radio system according to the first aspect is a communication of a loudspeaker signal.

In the third aspect of the present invention, the predetermined mode of the wide area broadcast radio system according to the first or second aspect is an ECB.
Mode, CBC mode, CFB mode, or OFB mode. Therefore, in communication, the loudspeaker mute release signal is encrypted and decrypted in the ECB mode or the like, thereby preventing loudspeaker mute release due to unauthorized communication.

[0012] In the invention of claim 4, claims 1 to 3 are provided.
The secret key information of the wide-area broadcast radio system described in any one of the above, employs a configuration based on encryption and decryption of a loudspeaker mute release signal. With this configuration, it is possible to prevent the loudspeaker voice mute from being released due to unauthorized communication by recording and reproducing the loudspeaker voice communication.

[0013] In the invention of claim 5, claims 1 to 3 are provided.
The secret key information of the wide-area broadcast radio system described in any one of the above items employs a configuration based on encryption and decryption of a loudspeaker mute release signal and a loudspeaker audio signal.

According to the sixth aspect of the present invention, the first to fifth aspects are provided.
The secret key information of the wide area broadcast radio system described in any one of the above items has a configuration including predetermined fixed information and variable information. With this configuration, the reliability of the secret key information is further improved.

In the invention of claim 7, the variable information of the wide area broadcast radio system according to claim 6 has a configuration including date and time information at the time of transmission. With this configuration, by applying date and time information at the time of transmission in addition to the predetermined information as common secret key information, it is more difficult to cancel the loudspeaker voice mute due to unauthorized communication by recording and playing back the loudspeaker voice communication. To

According to an eighth aspect of the present invention, there is provided a method for preventing an unauthorized loudspeaker from transmitting. The encryption processing step of a predetermined mode using secret key information in a predetermined communication from a transmitting device, and the secret information in a loudspeaker broadcast of a receiving loudspeaker. And a decryption process of a predetermined mode for preventing a loudspeaker broadcast due to unauthorized communication.

According to this configuration, a correct loudspeaker mute release signal and loudspeaker cannot be processed unless the transmitting device uses the proper secret key information, and a correct loudspeaker mute release signal and loudspeaker cannot be processed unless the receiver is a proper receiving loudspeaker. Cannot perform loudspeaker operation. Therefore, loudspeaker broadcasting due to unauthorized communication is prevented.

In the ninth aspect of the present invention, the communication of the method for preventing unauthorized loudspeaker voice according to the eighth aspect is a communication of a loudspeaker voice signal.

In the tenth aspect of the present invention, the predetermined mode of the method for preventing unauthorized loudspeaker speech according to the eighth or ninth aspect is characterized in that:
The configuration adopts any one of the CB mode, CBC mode, CFB mode, and OFB mode. In the communication of this configuration,
The loudspeaker mute release signal is encrypted and decrypted in the ECB mode or the like to prevent loudspeaker mute release due to unauthorized communication.

In the eleventh aspect of the present invention, the secret key information of the method for preventing unauthorized loudspeaker voice according to any one of the eighth to tenth aspects employs a configuration based on encryption and decryption of a loudspeaker voice mute release signal.

In the twelfth aspect of the present invention, the secret key information of the unauthorized loudspeaker prevention method according to any one of the eighth to tenth aspects is configured by encrypting and decrypting a loudspeaker mute release signal and a loudspeaker signal. Take.

According to a thirteenth aspect of the present invention, the secret key information of the method for preventing unauthorized loudspeaker speech according to any one of the eighth to twelfth aspects has a configuration including predetermined fixed information and variable information. With this configuration, the reliability of the secret key information is further improved.

According to a fourteenth aspect of the present invention, the variable information of the thirteenth aspect of the present invention employs a configuration including date and time information at the time of transmission. With this configuration, by applying date and time information at the time of transmission in addition to the predetermined information as common secret key information, it is more difficult to cancel the loudspeaker voice mute due to unauthorized communication by recording and playing back the loudspeaker voice communication. To

Next, with reference to the accompanying drawings, a wide-area broadcast radio system and a method for preventing unauthorized loudspeakers according to an embodiment of the present invention will be described in detail. FIG. 1 is a block diagram showing a configuration example of a wide-area broadcast radio system and a method of preventing unauthorized loudspeakers according to an embodiment of the present invention.

Referring to FIG. 1, an embodiment of a wide area broadcast radio system according to one aspect of the present invention includes a transmitting device 10 and a receiving loudspeaker 20. The wide-area broadcast wireless system according to this configuration is applied to the method of preventing unauthorized loudspeaker speech of the other invention.

In FIG. 1, one transmitting device 10 constituting the wide-area broadcast radio system includes an audio signal 1, a mute release signal 2, an encryption device 3, a KEY (also referred to as an encryption key) 4, and a transmitter 5. , Is configured. Further, the other reception loudspeaker 20 includes a receiver 6, a decoding device 7, and a KEY.
(Decryption key) 8 and a loudspeaker 9. Note that, in the receiving loudspeaker, the decoding device 7 to the loudspeaker 9
Is a mute release signal 21.

In the transmission device 10 having the above configuration, the audio signal 1 is an encoded digital signal. The mute release signal 2 is a digital signal for releasing the mute of the target receiving station. The encryption device 3 is an encryption device of the ECB mode, and performs an encryption process on a signal input using the KEY4. The encryption key (also called KEY) 4 is
This is an encryption key for performing the encryption process. The transmitter 5
It is a digital wireless transmitter, and performs wireless transmission processing by digitally modulating an input signal.

In the reception loudspeaker 20, the receiver 6 is a digital radio receiver, and receives a signal from the transmission device 5 and performs demodulation. The decryption device 7 performs a decryption process on the encrypted signal input using the KEY 8. The decryption key 8 is a decryption key for performing a decryption process. The loudspeaker 9 is controlled by the mute release signal 21 and performs loudspeaker broadcast processing.

An operation example of the wide-area broadcast radio system configured as described above will be described below. First, the digitally encoded audio signal 1 and mute release signal 2 are input to the encryption device 3. The encryption device 3 encrypts the input audio signal 1 and mute release signal using the KEY 4 and outputs the same to the transmitter 5. The transmitter 5 performs wireless transmission processing of the input digital signal.

The transmitted signal is received by the receiver 6 and demodulated. The demodulated signal is input to the decoding device 7. The decryption device 7 uses the KEY 8 to perform a decryption process on the input encrypted signal. The decoded audio signal is input to the loudspeaker 9. The loudspeaker 9 performs loudspeaker broadcasting of the input audio signal if the mute release signal 21 is correctly decoded. As described above, according to the embodiment of the present invention, by providing an encryption device and a decryption device for input and output of an audio signal and a mute release signal, a case of a correctly encrypted audio signal and a mute release signal is provided. Only the correct decoding can be performed, and the loudspeaker broadcasting can be performed only at this time.

In the above description, the encryption mode is set to EC
Although the description has been given of the example of the configuration in the B mode, the present invention can be similarly performed in other CBC mode, CFB mode, and OFB mode.

In the above description, an example has been shown in which both the audio signal and the mute release signal are encrypted / decrypted. However, when only the other audio signals are encrypted / decrypted, and only the mute release signal is used. The same applies to the case of encryption / decryption.

In the above description, the encryption key and the decryption key used for encryption and decryption are shown as fixed information. However, in addition to the fixed information as the encryption key and the decryption key, variable information such as transmission information is used. The same applies to the case where date and time information of time is applied.

[0034]

As is apparent from the above description, according to the present invention, a predetermined mode encryption process using secret key information is used between a transmitting device and a receiving loudspeaker.
With this configuration, the loudspeaker operation cannot be performed unless the correct loudspeaker mute release signal and loudspeaker sound are used. Therefore, loudspeaker broadcasting due to unauthorized communication is prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of a wide area broadcast wireless system according to an embodiment of the present invention;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 audio signal 2 mute release signal 3 encryption device 4 KEY (encryption key) 5 transmitter 6 receiver 7 decryption device 8 KEY (decryption key) 9 loudspeaker 10 transmission device 20 reception loudspeaker 21 mute release signal

Claims (14)

[Claims] 1. A transmission device comprising an encryption device of a predetermined mode using secret key information in a predetermined communication, and a decoding device of the predetermined mode using the secret information to prevent a loudspeaker broadcast by unauthorized communication. A wide-area broadcast radio system, comprising: 2. The wide area broadcast radio system according to claim 1, wherein said communication is communication of a loud voice signal. 3. The method according to claim 1, wherein the predetermined mode is an ECB mode or a CB mode.
3. The wide area broadcast radio system according to claim 1, wherein the system is any one of a C mode, a CFB mode, and an OFB mode. 4. The wide area broadcast radio system according to claim 1, wherein said secret key information is constituted by encrypting and decoding a loudspeaker mute release signal. 5. The wide area broadcast according to claim 1, wherein the secret key information is formed by encrypting and decoding a loudspeaker mute release signal and a loudspeaker signal. Wireless system. 6. The wide area broadcast radio system according to claim 1, wherein said secret key information is composed of predetermined fixed information and variable information. 7. The wide area broadcast radio system according to claim 6, wherein the variable information includes date and time information at the time of transmission. 8. An encryption processing step of a predetermined mode using secret key information in a predetermined communication from a transmission device, and a loudspeaker broadcast by an unauthorized communication is prevented by using the secret information in a loudspeaker broadcast of a reception loudspeaker. And a decoding process in the predetermined mode. 9. The method according to claim 8, wherein the communication is communication of a loudspeaker signal. 10. The predetermined mode is an ECB mode, C
The method according to claim 8 or 9, wherein the method is any one of a BC mode, a CFB mode, and an OFB mode. 11. The method according to claim 8, wherein the secret key information is formed by encrypting and decoding a loudspeaker mute release signal. 12. The unauthorized loudspeaker according to claim 8, wherein said secret key information is formed by encrypting and decoding a loudspeaker mute release signal and a loudspeaker signal. Prevention method. 13. The method according to claim 8, wherein the secret key information is composed of predetermined fixed information and variable information. 14. The method according to claim 13, wherein the variable information includes date and time information at the time of transmission.