JP2806702B2 - Digital cordless button telephone device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital cordless key telephone apparatus.

[0002]

2. Description of the Related Art In a conventional digital cordless button telephone device, when a connection device detects the presence or absence of a carrier signal from a portable telephone, there is no means for notifying the control unit of the main device from the connection device of the presence or absence of the carrier signal. If the disconnection of the carrier signal is detected, the communication between the mobile phone and the connection device is disconnected, the connection device notifies the control unit of the main device using the call control channel, and the control unit of the main device notifies the other party of the call. The processing of disconnecting the communication path with the mobile phone was performed.

[0003]

In the above-mentioned conventional digital cordless button telephone device, the control unit of the main device does not directly notify the disconnection of the carrier signal, and the communication between the portable telephone and the connection device is disconnected. Since the notification is made using the call control channel, if the mobile phone temporarily goes out of the range of the connection device, the connection control device determines that the call has been disconnected. There is a problem that noise is transmitted to the communication path until the main apparatus is notified using the channel.

[0004]

SUMMARY OF THE INVENTION A digital cordless button telephone device of the present invention includes a plurality of connection devices for connecting to a plurality of portable telephones via a wireless line, a plurality of telephone lines, and a plurality of telephone lines. A main unit for accommodating the plurality of connection devices, wherein the connection device transmits and receives signals to and from the plurality of mobile phones, and a first circuit for detecting the presence or absence of a carrier signal from the mobile phones during a call.
And a predetermined digital code signal is inserted into the B channel or additional control bit of the transmission frame configuration at the S / T point of the ISDN line for the main unit according to the detection signal from the first detection circuit. A digital code insertion circuit, a first basic interface circuit having a basic interface for the ISDN line, wherein the main device has a second basic interface circuit having a basic interface for the ISDN line;
A second detection circuit for detecting the presence or absence of the digital code signal from the B channel or the additional control bit of the output of the second basic interface circuit, and a case where the second detection circuit detects the digital code signal An idle signal insertion circuit for inserting an idle signal indicating silence into the PCM signal path of the second basic interface circuit; a line interface circuit including a codec circuit for interfacing with the plurality of telephone lines; A communication path switch for forming a digital communication path for the second basic interface circuit, and wherein the digital code insertion circuit includes
The predetermined digital code signal is inserted into a specific bit corresponding to the communication channel of the B channel of the transmission frame configuration at the S / T point of the SDN line, or the digital code insertion circuit connects the ISDN line to the main unit. The predetermined digital code signal is inserted into the multi-frame bits of the transmission frame configuration at the S / T point, or the digital code insertion circuit is configured to reserve the transmission frame configuration at the S / T point of the ISDN line for the main unit. The predetermined digital code signal is inserted into bits.

[0005]

Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a digital cordless button telephone apparatus according to one embodiment of the present invention.

In FIG. 1, a digital cordless button telephone apparatus according to the present embodiment includes portable telephones 15 and 16 and a connecting device 1 for accommodating the portable telephones 15 and 16 via a wireless line.
0, and the main device 1 that accommodates the telephone line 17 and the connection device 10.

[0008] The connection device 10 includes a transmitting / receiving circuit 13 for transmitting and receiving a carrier signal for a call to and from the mobile phones 15 and 16, a detection circuit 14 for detecting the presence or absence of a carrier signal during a call, and a carrier signal for a call being detected. If not, a digital code insertion circuit 12 that inserts a predetermined digital code signal into the B channel or additional control bits of the frame structure at the S / T point of the ISDN, and an IS connected to the main device 1
A basic interface circuit 11 for interfacing with the DN line 9 is provided.

The main unit 1 includes a basic interface circuit 7 for interfacing with the ISDN line 9, a detection circuit 5 for detecting a predetermined digital code signal from a B channel or an additional control bit in a frame received from the connection unit 10. When the detection circuit 5 detects a predetermined digital signal, the idle signal insertion circuit 3 that inserts an idle signal indicating silence into the PCM signal path, the digital communication path switch 8, the telephone line 7 and the communication path switch 8, It comprises a line interface circuit 2 for interfacing and a control circuit 6 for controlling the entire main device 1.

Next, the operation of this embodiment will be described.
When a key operation for making a call from the mobile phone 15 to the mobile phone 16 is performed, the mobile phone 15 transmits a call signal using a wireless control channel. At this time, the connection device 10 waits for the presence or absence of the carrier signal from the mobile phones 15 and 16. When the transmission / reception circuit 13 and the detection circuit 14 of the connection device 10 receive the carrier signal of the call signal of the mobile phone 15, the transmission / reception circuit 13 sends a response signal to the mobile phone 15 to secure a communication channel. At the same time, the connection information of the call signal is transmitted to the basic interface 7 and the control circuit 6 of the main unit 1 via the digital code insertion circuit 12, the basic interface circuit 11, and the D channel (control channel) of the ISDN line 9.

The control circuit 6 sends an incoming call signal to the portable telephone 16 to the transmission / reception circuit 13 of the connection device 10 via the D channel of the basic interface, based on the connection information, in a route reverse to that at the time of calling. . The transmission / reception circuit 13 transmits an incoming call signal using a wireless control channel. Mobile phone 16
Is in a state of waiting for an incoming call signal, receives the incoming call signal, and responds by key operation. By the response operation, the mobile phone 16 sends a response signal to a wireless control channel. The transmission / reception circuit 13 of the connection device 10 receiving the response signal secures a communication channel and sends the response signal to the control circuit 6 of the main device 1. The control circuit 6 controls the communication path switch 8 to connect the communication channels of the mobile phone 15 and the mobile phone 16 to enable communication.

At this time, if the portable telephone 15 goes out of the range of the connection device 10, the transmission / reception circuit 13 and the detection circuit 14 of the connection device 10 detect the disconnection of the carrier signal of the call from the portable telephone 15, and The connection device 10 notifies the main device 1 of the disconnection of the carrier signal by any one of the methods (1) to (4).

(1) P of communication channel of transmitting / receiving circuit 13
A specific digital code for communication disconnection predetermined by the digital code insertion circuit 12 is set in the CM signal path as the absence of a carrier signal.
Basic interface circuit 7 of main unit 1 via N line 9
To send to.

(2) P of communication channel of transmitting / receiving circuit 13
One of the communication channels is used as a control channel by a digital code insertion circuit 12 in the CM signal path, and a digital code without a carrier signal is used for a bit corresponding to the channel number in the B channel of the basic interface circuit 11 and the ISDN line 9.
To the basic interface circuit 7 of the main device 1 via the

(3) The digital code insertion circuit 12 inserts a digital code without a carrier signal by inserting it into a multiframe bit (M bits) at the S / T point of the ISDN of the basic interface circuit 11 via the ISDN line 9. 1 to the basic interface circuit 7.

(4) The digital code insertion circuit 12 inserts a spare code (S bit) at the S / T point of the ISDN of the basic interface circuit 11 into a digital code without a carrier signal via the ISDN line 9. To the basic interface circuit 7.

Next, in response to the carrier-less signal received via the basic interface circuit 7 of the main unit 1, the detection circuit 5 detects the signal corresponding to the notified methods (1) to (4). The transmission procedure of the idle signal (silence signal) is taken.

(1) When a predetermined specific digital code is detected from the B channel of the basic interface circuit 7, an idle signal indicating silence is sent from the idle signal insertion circuit 3 to the communication path while the specific digital code is detected. Send it to switch 17.

(2) An idle signal (silence signal) is inserted into the idle signal insertion circuit 3 while the digital code without a carrier signal is detected in the bit corresponding to the channel number from the B channel used as the control channel of the basic interface circuit 7 From the communication path switch 8.

(3), (4) Basic interface circuit 7
The idle signal (silence signal) is transmitted from the idle signal insertion circuit 3 to the communication path switch 8 while the digital code without a carrier signal is detected from the additional control bits (M bits, S bits) of the.

Next, the speech path switch 8 inserts the transmitted idle signal into the speech channel used by the mobile phone 16. As a result, no noise is transmitted to the mobile phone 16 even when the carrier is interrupted during a call.

[0022]

As described above, according to the present invention, when disconnection of a carrier signal from a portable telephone is detected by a connection device,
The disconnection of the carrier signal from the connection device is converted into a digital code, inserted into the B channel of the basic interface of ISDN or additional control bits (M bit, S bit) and transmitted to the main device, so that the mobile phone can be connected during a call. Since the main unit can recognize when the device goes out of the service area or instantaneous interruption in real time, the load on the control channel is reduced, and the noise that occurred before the call was recognized as being disconnected can be eliminated. Has an effect.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a digital cordless button telephone device according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main apparatus 2 Line interface circuit 3 Idle signal insertion circuit 5 Detection circuit 6 Control circuit 7 Basic interface circuit 8 Communication path switch 9 ISDN line 10 Connection device 11 Basic interface circuit 12 Digital code insertion circuit 13 Transmission / reception circuit 14 Detection circuit 15 Mobile phone 16 Mobile phone 17 Telephone line

Claims (4)

(57) [Claims] 1. A plurality of connection devices that connect to a plurality of mobile telephones via a wireless line, and a main device that accommodates a plurality of telephone lines and accommodates the plurality of connection devices via an ISDN line, The connection device includes a transmission / reception circuit that performs wireless transmission / reception with the plurality of mobile phones, a first detection circuit that detects presence / absence of a carrier wave signal from the mobile phone during a call, and detection from the first detection circuit. A digital code insertion circuit for inserting a predetermined digital code signal into a B channel or an additional control bit of a transmission frame structure at an S / T point of the ISDN line for the main unit by a signal; and a basic interface for the ISDN line. A first basic interface circuit, wherein the main unit comprises a second basic interface circuit having a basic interface to the ISDN line. This interface circuit and the second
A second detection circuit for detecting the presence or absence of the digital code signal from the B channel or the additional control bit of the output of the basic interface circuit, and the second detection circuit when the second detection circuit detects the digital code signal. An idle signal insertion circuit for inserting an idle signal indicating silence into the PCM signal path of the second basic interface circuit, a line interface circuit including a codec circuit for interfacing with the plurality of telephone lines, the line interface circuit and the second And a communication path switch forming a digital communication path for the basic interface circuit. 2. The digital code insertion circuit inserts the predetermined digital code signal into a specific bit corresponding to a B channel communication channel of a transmission frame configuration at an S / T point of the ISDN line to the main device. The digital cordless button telephone device according to claim 1, wherein: 3. The digital code insertion circuit according to claim 1, wherein the digital code insertion circuit inserts the predetermined digital code signal into multi-frame bits of a transmission frame configuration at an S / T point of the ISDN line for the main unit. 1
Digital cordless button telephone device as described. 4. The digital code insertion circuit according to claim 1, wherein the predetermined digital code signal is inserted into spare bits of a transmission frame configuration at an S / T point of the ISDN line for the main unit. Digital cordless button telephone device as described.