JPH0563774A - Isdn digital telephone system - Google Patents

Abstract

PURPOSE:To obtain the ISDN digital telephone system in which the talking charge in the case of extension talking is not required and B-channel blocking state is avoided. CONSTITUTION:Information representing an extension talking request is set to a user user information element in any telephone set and a setup message with the user user information element added thereto is sent to a connector 2, then the connector 2 does not return the received setup message to the ISDN and the setup message using the content of an incoming address/incoming subaddress information element as an extension number is generated. Then the message is returned to the ISDN telephone set to call the message and both caller and called telephone sets are set to a same B-channel. As a result, the extension talking free of charge not through the ISDN is implemented by a reply of the called telephone set and in this case, since other B-channel is idle, the external talking and the extension talking are attained by other telephone set. Furthermore, in the case of the extension talking, the side tone of the relevant telephone set is adjusted to a proper value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection device connected to an ISDN network and a plurality of ISDs connected to this connection device.
The present invention relates to an ISDN digital telephone device composed of N telephones.

[0002]

2. Description of the Related Art Generally, one ISDN line has a DSU
Up to eight ISDN telephones can be connected in a bus format via the (line terminating device). When making extension calls between ISDN telephones accommodated in this one ISDN line, operate the dial keys. If you enter the dial number corresponding to this ISDN line, then enter the subaddress and make a call to the ISDN network, the ISDN line accommodated in this ISDN line and the incoming call arrives at the ISDN telephone set corresponding to the above subaddress. Applicable ISDN
The extension mutual call is made by the response of the telephone.

[0003]

However, when an extension mutual call is made between telephones accommodated in such one ISDN line, if the B2 channel is set to the ISDN telephone on the calling side, the called side is called. Since the ISDN telephone set has the B1 channel set, the signal channels for two calls are blocked, so that other ISDN telephones cannot make an outside call or an extension call until this extension call ends. was there.

[0004]

In order to solve such a problem, the present invention provides an ISDN telephone apparatus comprising a connection device connected to an ISDN network and a plurality of ISDN telephones connected to the connection device. In the above, the connection device is provided with means for setting the same call signal channel to the calling ISDN telephone and the called ISDN telephone when performing an extension call between a plurality of ISDN telephones. Further, the ISDN telephone is provided with a side tone adjusting means for making an extension call.

[0005]

In the extension call, the same call signal channel is set for the calling side telephone and the called side telephone. In addition, the same call channel is set and the sidetones of both telephones during the extension call are adjusted to appropriate values.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 4 is a connection configuration diagram of the ISDN telephone device according to the present invention, and shows an example in which the connection device 2 is arranged between the DSU 1 terminating one ISDN line and a plurality of ISDN telephones 4a to 4n. Further, FIG. 5 shows that a plurality of ISs are added to the DSU 3 in which the function of the connection device 2 is added to the function of the DSU 1.
An example is shown in which DN telephones 4a to 4n are connected. FIG. 1 is a block diagram showing an embodiment of the ISDN telephone device of the present invention, which shows a configuration corresponding to the connection device 2 described above. Further, FIG. 2 is a block diagram of the DSU 3 having the function of the DSU 1 and the function of the connection device 2. Note that FIG. 3 is a block diagram of the ISDN telephone 4.

First, the connection device 2 shown in FIG.
0, ROM 21, RAM 22, transformers 23, 29, driver / receivers 24, 28, I interface circuits 25, 27, B channel exchange unit 26, connection detection unit 30,
It is composed of the connection circuit 31 at the time of power failure, the DC / DC converter 32, the switch 33, the AC power receiving section 34, the AC adapter 35 and various clock signals a to c, and the portion surrounded by the dotted line in the figure is the T point. It is the / S point control unit 10. It should be noted that the DSU 1 is connected to the T point side indicated by the X mark, and the ISDN telephone 4 is connected to the S point side. Further, B1 and B2 indicate a B channel which is a signal channel for communication, and D is a data bus for the D channel control and other control by the CPU 20.

Note that the B1 and B2 channels are replaced by the CPU
It is performed by the B channel switching unit 26 based on the instruction of 20. For example, as shown in FIG. 8, the setting of the B channel when an extension telephone call is made between ISDN telephones is performed by receiving a call setting message from the calling telephone 4a and receiving the telephone 4b.
If, for example, the B1 channel is set to the called telephone 4b when the call setting message is returned to the calling telephone 4a, the B1 of the same channel as the above is sent to the calling telephone 4a when the call setting acceptance message is transmitted to the calling telephone 4a. The channel is set.

Further, as shown in FIG. 2, the DSU 1
3 is a block diagram of a DSU 3 equipped with the functions of a connection device 2 and the DSU 3, which includes the T point / S point control unit 10, the interface circuit unit 11, and the line termination circuit unit 1 described above.
3, a driver 14, a transformer 15, and a power supply circuit 16, and the ISDN lines L1 and L2 are connected to the transformer 15.

Further, FIG. 3 shows the ISDN as described above.
FIG. 3 is a block diagram of the telephone set 4, which includes a control unit 40, a setting unit 41, and an extension key 4 used during extension calls.
2, a display unit 43 for performing various displays, an operation unit 44 including a dial key, a sub address key for inputting an extension number, a transmission key, etc., a line I / F unit 45 for interfacing with an ISDN line, various types Analog signal control unit 46 that generates a tone signal or the like, a codec 47 that performs analog / digital conversion of a voice signal, a sidetone adjustment circuit 48 that adjusts the sidetone of the telephone during an extension call, a handset 49, an AC power supply 50, The connection device 2 is composed of an AC adapter 51, a power supply switching unit 52, and a power supply unit 53 that supplies power to each unit of the telephone.
Or it is connected to DSU3.

Next, FIG. 6 is a block diagram showing a main part of the sidetone adjusting circuit 48 in the ISDN telephone 4. The sidetone adjusting circuit 48 includes a sidetone adjusting section 60, amplifiers 61, 62, and
And a sidetone addition circuit 63. The sidetone adjusting circuit 48 operates under the control of the control unit 40 only during an extension call, and can provide an optimum sidetone in terms of call quality. Generally, the transmission signal from the transmitter T in the handset 49 is transmitted to the other party and, at the same time, is heard as a reception signal from the receiver R. However, during the extension call, as described above, since the same B channel is used for the calling side telephone and the called side telephone, the transmission signal heard from the receiver R, that is, the side tone becomes abnormally loud and the telephone call becomes abnormal. Not good for quality. For this reason, the side tone adjusting circuit 48 is provided so that the side tone adjusting circuit 48 is activated only during an extension call.

FIG. 7 is a timing chart showing the operation of such a side tone adjusting circuit 48. When the waveform shown in (a) of FIG. 7 is used as the transmission signal from the transmitter T and the waveform shown in (b) is used as the transmission signal of the other party, a call is made using the same B channel and the sidetone adjustment circuit is used. The waveform of the reception signal heard from the receiver R when 48 is not provided is as shown in (c), and the transmission signal waveform of (b) is added to the transmission signal waveform of (a). Will be things.
Therefore, by providing the sidetone adjusting circuit 48 and operating the sidetone adjusting circuit 48, the transmission signal of (a) is subtracted from the reception signal of (c) [that is, as shown in (d). An opposite phase signal of the transmission signal is generated and adjusted by adding it to the reception signal of (c)] to obtain an optimum reception signal as shown in (e). In this embodiment, the analog signal is processed to obtain the optimum received signal, but the same result can be obtained by processing the digital signal itself using a DSP or the like.

Next, in FIG. 8, the connection device 2 (or DSU 3) is provided between the ISDN network and the ISDN telephone 4, and I
It is a sequence diagram which shows operation | movement in the case of being comprised so that extension telephone call can be performed, without going through SDN network. This is ISD
An example is shown in which extension telephone call request information is set in the user / user information element in the N telephone set 4a and a call setup message to which this user / user information element is added is transmitted to make an extension telephone call with the ISDN telephone set 4b. .. In this case, the extension call does not go through the ISDN network, so it is a free call. That is, when the extension key 42 is pressed on the ISDN telephone 4a, the extension call request information is set in the user / user information element, and the operation unit 44 is operated.
When the dial or subaddress for calling the ISDN telephone 4b is input by operating the dial key or the like, these input data are set in the destination address information element or the destination subaddress information element. Then, when the transmission key in the operation unit 44 is pressed, a call setting message to which the above-mentioned information elements are added is created and transmitted to the connection adapter 2.

When the connection device 2 receives the call setup message from the telephone set 4a and determines that the content of the user / user information element added to this message is extension call request information, the received call setup message is received. ISDN
Without sending to the network, a call setup message with the contents of the destination address information element and the destination subaddress information element of this message as an extension number is created and transmitted to the ISDN telephone 4b, and at the same time, a call channel to the telephone 4b. For example, the B1 channel is set.

When an extension call is made to the telephone set 4b in this way, and then a call setting acceptance message and a call message are transmitted from the called side telephone 4b, the connection unit 2 sends a call setting acceptance message to the calling side telephone 4a. And the B1 channel, which is the same channel as the above, is set as the call channel for the telephone 4a. After that, when the telephone 4b responds to this call, the connection unit 2 sends and receives various messages to and from the telephones 4a and 4b and shifts to the extension call state. In this way, the control of the connection device 2 enables a free extension call without going through the ISDN network. In addition, since the same call channel is set under the control of the connection device 2 during an extension call, another call channel (for example, B2 channel) is in an unused state, and another ISDN telephone set via this unused channel. Can make an outside call or an extension call.

Next, FIGS. 9A and 9B show ISDN.
A control unit 40 that controls the sidetone adjustment circuit 48 in the telephone 4.
3 is a flowchart showing the operation of FIG. First, (a) of FIG. 9 will be described. As described above, since the same B channel is used during extension calls, the side tone of the telephone becomes loud. Therefore, after the off-hook is detected in the ISDN telephone 4, the extension key 42 is detected in step 100.
If it is determined that the extension key 42 has been pressed and it is determined to be “Y”, the extension sound is transmitted, and the side tone adjusting unit 60 is activated in step 101. After that, the various messages as described above are transmitted and received to and from the connection device 2, and in step 102, the state is changed to the extension call state. When the extension call is established in this way, next step 1
In 03, the on-hook is judged. When the on-hook for ending the extension call is performed, the side tone adjusting unit 60 is made inoperative in step 104.

As described above, in the calling side telephone,
When the extension key 42 is pressed, the sidetone adjusting section 60 is activated to obtain the optimum sidetone in the extension call. In the case of the called ISDN telephone, the side tone adjusting unit 60 is activated by obtaining specific information from the connection device 2 when the extension call is formed, or a call setting message from the connection device 2 is sent. Destination address added to /
Sidetone adjustment unit 6 based on the content of the destination subaddress information element
It is also possible to set 0 to the operating state.

If the pressing of the extension key 42 is not detected and it is judged as "N" in step 100, it means that the outside line is transmitted, and the side tone adjusting section 60 is controlled in the inoperative state in step 105. After that, a dial operation is performed, and after sending and receiving various messages, step 106 is performed.
The call goes to the outside line. When the on-hook for ending the call is detected and it is determined to be "Y" in step 107, the process ends.

Further, FIG. 9B shows a side tone adjusting circuit 48.
8 is a flowchart showing the operation of another embodiment of the control unit 40 that controls the above. That is, when the ISDN telephone 4 is off-hooked and the dial operation is performed in step 150, the dial number is checked and step 151
Then, it is judged whether or not this dial number is an extension number. And this dial number is this ISDN telephone 4
If the dial number is the same as that of the ISDN line connected to, and it is determined to be "Y" in step 151, the side tone adjusting section 60 is controlled in steps 152 to 155. These processing controls are shown in FIG. 9 (a) described above.
Since it is the same as the processing control in steps 101 to 104, the description thereof will be omitted. Further, when the operated dial number does not correspond to the extension number and it is determined to be “N” in step 151, the processing control for disabling the side tone control unit 60 shown in step 156 and thereafter is executed.

[0020]

As described above, according to the present invention, the same call signal channel is set for both the calling side and called side telephones during an extension call, so that the other telephones can be used. Even when an extension call is being made, another call signal channel is vacant, and in this case, there is an effect that an external call or an extension call can be performed using the vacant channel. In addition, since the sidetone can be adjusted to an appropriate value when an extension call is made using the same call signal channel, good call characteristics can be obtained.

[Brief description of drawings]

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

FIG. 2 is a block diagram showing another embodiment of the ISDN digital telephone device.

FIG. 3 is a view showing I constituting the above ISDN digital telephone device.
It is a block diagram of an SDN telephone.

FIG. 4 is a connection configuration diagram of the ISDN digital telephone device.

FIG. 5 is a connection configuration diagram of the ISDN digital telephone device.

FIG. 6 is a block diagram of a side tone adjusting circuit in the ISDN telephone.

FIG. 7 is a timing chart of the side tone adjustment circuit.

FIG. 8 is a sequence diagram showing an operation of the ISDN digital telephone device.

FIG. 9 is a flowchart showing the operation of the ISDN telephone.

[Explanation of symbols]

 1, 3 DSU 2 connection device 4 ISDN telephone 10 T point / S point control unit 11 interface circuit unit 12 line termination circuit unit 13 transmission line termination circuit unit 20 CPU 25, 27 I interface circuit 26 B channel switching unit 40 control unit 42 Extension key 44 Operation unit 45 Line I / F unit 46 Analog signal control unit 47 Codec 48 Sidetone adjustment circuit 49 Handset 60 Sidetone adjustment unit 61, 62 Amplifier 63 Sidetone addition circuit T transmitter R receiver

Claims (2)

[Claims] 1. An ISDN digital telephone device comprising a connection device connected to an ISDN network and a plurality of ISDN telephones connected to the connection device, both of which are used when an extension call is made between the plurality of ISDN telephones. An IS characterized in that the connection device is provided with means for setting the same call signal channel in the ISDN telephone.
DN digital telephone device. 2. The ISDN digital telephone device according to claim 1, wherein the ISDN telephone is provided with a side tone adjusting means for adjusting a side tone of the ISDN telephone when performing an extension call. apparatus.