JPH04269030A - Radio communication equipment - Google Patents

Abstract

PURPOSE:To attain ciphering processing without data transmission reception exclusively used for a key code by using a key code so as to convert an original, voice signal into a ciphered voice at a sender side and obtaining the key code based on a speech channel in use at a receiver side so as to decode the ciphered voice. CONSTITUTION:A voice processing circuit 5 implements ciphering processing by using the frequency division replacement method which is a method dividing a voice band into small bands and replaces them. The circuit 5 converts a voice signal (original voice signal) fed through a telephone line L and a network circuit 6 into a ciphered voice signal and it is fed to a transmission circuit 4. The circuit 5 decodes an output signal (ciphered voice signal) from a reception circuit 3 into a decoded voice signal and gives the result to the circuit 6. A bell signal detection circuit 7 detects a bell signal at the arrival of a call and gives a detected output to a control circuit 8. The control circuit 8 controls the entire master set and closes a switch contact (not shown) in the circuit 6 based on a signal from a slave set included in the reception signal from the circuit 3 to connect the line L and generates a dial signal by using the dial number data from the slave set.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication device such as a cordless telephone device having a private conversation function.

0002

[Background Art] In recent years, wireless communications such as car phones and cordless telephone devices have become more commonplace, and at the same time, wireless devices that intercept them have also become easily available, and are now equipped with confidential communication functions for the purpose of protecting privacy. It's coming.

[0003] The secret method is, for example, published in the Journal of the Institute of Electronics, Information and Communication Engineers (
Vol. 70 1987-12), there are two main types of secrets: digital secrets and analog secrets.
And analog secret stories include frequency inversion method, frequency transition method,
There are spectral rotation method and frequency division permutation method.

By the way, in these secret message systems, it is important that the decoding quality is good and that the decoding is difficult.
For this latter purpose, it is necessary to have a large number of keys for polarization, that is, how many patterns of polarization can be converted from the original sound. For example, the number of keys in the frequency division permutation method is the number of recombinations of divided bands.

[0005]

[Problem to be Solved by the Invention] When employing a secret communication system having a predetermined number of keys as described above, it is difficult to determine which pattern (in the frequency division permutation method, the divided band It is notified by predetermined data (hereinafter referred to as key code) whether the voice has been converted into a secret voice using the recombination pattern).
This will normally be placed on the control channel.

However, if a key code is placed on the control channel in this way, the usage time of the control channel becomes longer.For example, in a system where there are many fixed telephones, such as a cordless telephone in a premises, there are calls from multiple fixed telephones at the same time. If the key code is sent and received incorrectly, the confidential tone will be decoded using a different pattern, resulting in poor communication. Became.

[0007]

[Means for Solving the Problems] A wireless communication device of the present invention includes a fixed device and a mobile device connected by radio,
In the transmitting side, the original sound is converted into a confidential voice using a key code based on a predetermined confidential communication method, and the receiving side decodes the confidential voice using the key code, and the fixed device and the mobile device are configured to The key code is determined based on the key code.

[0008]

[Operation] Since the present invention is configured as described above, the transmitting side converts the original sound into a secret tone using a key code determined based on the communication channel to be used, and the receiving side converts the original sound to a secret tone using the key code determined based on the communication channel to be used. The key code is determined based on the key code, and the secret speech is decoded using this key code.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings, taking an analog cordless telephone device as an example. FIG. 1 shows a block diagram of a base unit (1) of the present invention, (3) is a receiving circuit that receives and demodulates a signal from a slave unit (2), (4) is a receiving circuit that FM modulates an input signal, This is a transmitting circuit that transmits data to the handset (2). (5) is a voice processing circuit that performs confidential speech processing using the frequency division and replacement method, which is a method of dividing the voice band into small bands and replacing them.
6) is converted into a secret speech signal and supplied to the transmitter circuit (4), and the output signal (original speech signal) from the receiver circuit (3) is converted into a secret speech signal. It decodes the signal and supplies it to the network circuit (6). (7) is a bell signal detection circuit that detects a bell signal when an incoming call is received, and provides a detection output to a control circuit (8). (8)
is the control circuit that controls the entire base unit, and the receiving circuit (3)
A switch contact (not shown) in the network circuit (6) is closed based on the signal from the handset included in the received signal from the handset (1), and the telephone line (L) is connected.
It generates a dialing signal based on the dialing number data and controls it to make a dialing call. Also, control circuit (8)
is designed to give a key code to the audio processing circuit (5).

FIG. 2 shows a block diagram of the handset, where (9) is a receiving circuit that receives and demodulates the signal from the base unit (1), and sends the demodulated signal (private voice signal) to the base unit (1). The signal is supplied to an audio processing circuit (10) having the same configuration as the audio processing circuit (5). Incidentally, the complex tone signal from the audio processing circuit (10) is sent to the amplifier (
The sound is amplified by the receiving speaker (12) via the receiver (11). (13) converts the secret voice signal from the audio processing circuit (10) and the control signal from the control circuit (15) into FM
This is a transmitting circuit that modulates and transmits to the base unit (1). Note that the audio processing circuit (10) converts the audio signal (original sound signal) from the microphone (14) into a confidential audio signal and sends it to the transmission circuit (1
3). The control circuit (15) operates to transmit control signals and dial number data to the base unit (1) based on key signals from a keyboard (16) consisting of a numeric keypad, a call key, a cut key, etc. The key code is then given to the audio processing circuit (10). (17) is a notification speaker that generates notification sound under the control of the control circuit (15).

Next, the operation of the above configuration will be explained. It is assumed that the cordless telephone device of the present invention has two control channels and 80 communication channels.

First, the case where an incoming call from the telephone line (L) is detected will be explained. The control circuit (8) of the base unit (1) that detects the incoming call causes the receiving circuit (3) to search for a communication channel and captures an empty channel. and,
When an empty channel is captured, the receiver circuit (3) and transmitter circuit (4) are set to the control channel, and the identification number code (to indicate that the base unit and slave unit are paired), incoming call detection signal, Sends a control signal including idle call channel number data to handset (2). After that, when the handset (2) in the reception standby state receives a control signal from the base unit (1), it transmits a response signal to the base unit (1), and then the base unit (
1) Switch to the communication channel announced from 1). Furthermore, the base unit (1) that has detected the response signal similarly switches to the corresponding communication channel, and transmits a ringer ringing signal to the slave unit on this channel. The control circuit (15) of the handset (2) that has detected the ringer sound signal drives the notification speaker (17) to notify the ringer sound. When the user operates the call key of the handset (2) in response to this ringer sound, the control circuit (15) of the handset (2) will transmit an off-hook signal, and the parent who received this off-hook signal The control circuit (8) of the machine (1) connects to the telephone line (
This will conclude L). After that, it becomes possible to talk to the caller, but at this time, the control circuits (8) and (15) of the base unit (1) and handset (2) calculate the call channel number + identification code number + 1. The value of the lower first digit is determined as the key code, and this key code is used in the audio processing circuit (5) (10
). For example, if the call channel number is 24 and the identification number is 52, 24+52+1=77
Therefore, the key code is 7. The voice processing circuits (5) and (10) that have received this key code perform secret speech processing using a pattern based on this key code.

[0013] By this process, 10 key codes from 0 to 9 can be obtained, and since the constant "identification code number" and "1" are added to the call channel number, The key code is difficult to decipher. Furthermore, when a communication channel between a parent and child is formed, the key codes between the parent and child always match, so it is possible to prevent call failures due to mismatched key codes.

[0014] From now on, a call is made in this state, but when the cut key of the handset (2) is operated, the control circuit (15) of the handset (2) sends an end signal to the base unit (1). Detecting this, the control circuit (8) of the base unit (1) releases the connection of the telephone line (L). Further, as a result, each of the base unit (1) and the slave unit (2) returns to the reception standby state.

Next, the case of making a dial call from the handset (2) will be explained. When the call key of the handset (2) is operated, the control circuit (15) of the handset (2) switches to the receiving circuit (9).
Search for a communication channel and capture an empty channel. When an empty channel is captured, the receiver circuit (9) and transmitter circuit (13) are set to the control channel, and a control signal including an identification code, a calling signal, and a call channel number data is transmitted to the base unit (1). . Upon detecting this control signal, the control circuit (15) of the base unit (1), which is in a reception standby state, transmits a response signal to the slave unit (2) and connects to the communication channel notified by the slave unit (2). Switch. Furthermore, the base unit (1) that has detected the response signal similarly switches to that communication channel, and transmits a switching completion signal to the base unit (1) through this communication channel. The control circuit (8) of the base unit (1) that has detected this switching completion signal closes the telephone line (L) via the network circuit (6). At this time, the control circuit (15) of the master unit (1) and slave unit (2)
calculates a key code using a method similar to that described above, and provides this key code to each of the audio processing circuits (5) and (10).

[0016] Then, after the telephone line (L) is closed and the dial tone is played from the receiving speaker (12) of the handset (2), when the numeric keypad of the handset (2) is operated. , the control circuit (15) of the slave unit (2) sends the dial number data to the base unit (1), and the control circuit (8) of the base unit (1) that detects this sends the dial number data via the network circuit (6). A dial call will be made. As a result, once the call state is established, the subsequent steps are the same as in the case of receiving a call as described above.

Note that in the above configuration, "1" is added when calculating the key code, but any natural number may be used.

Furthermore, in the above configuration, since the communication channel is not fixed, when searching for an empty channel, it is desirable to search from the channel next to the previously used channel.

[0019]

Effects of the Invention As described above, in the present invention, the transmitting side converts the original sound into a secret voice using a key code determined based on the communication channel to be used, and the receiving side converts the original sound into a secret tone based on the key code determined based on the communication channel to be used. Since the code is used to decode the secret voice, there is no need to send and receive data dedicated to the key code between the fixed device and the mobile device, and the time required to use the control channel can be shortened. Furthermore, if a communication channel is formed between the fixed device and the mobile device, the key codes of the fixed device and the mobile device will always match, and poor communication can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a base unit of a cordless telephone device according to the present invention.

FIG. 2 is a block diagram of a slave unit.

[Explanation of symbols]

1 Base unit 2. Handset 5 Audio processing circuit 8 Control circuit 10 Audio processing circuit 15 Control circuit

Claims (1)

[Claims] 1. A fixed device and a mobile device are connected by radio, and a transmitting side converts an original sound into a secret sound using a key code based on a predetermined secret method, and a receiving side converts the secret sound into a secret sound using a key code. 2. A wireless communication device in which the fixed device and the mobile device determine the key code based on a communication channel to be used.