JPS61129956A - electronic exchange conference trunk - Google Patents

Abstract

PURPOSE:To prevent a pushbutton signal tone from being listened to other subscribers by detecting the pushbutton transmitted from a subscriber for a service request during conference talking and eliminating immediately. CONSTITUTION:When a meeting halfway withdrawal request is generated from a telephone set 1 of a subscriber during conference talking, the pushbutton signal is digitized and multiplexed. Then a multi-frequency signal reception circuit 3 detects the signal, applies interruption to a microprocessor 6, and the button signal is outputted to a selector 7 to inform a time slot number corresponding to the telephone set 1 from which the button signal is outputted. Since the multi-frequency signal reception circuit 4 receives and informs the button signal, the processor 6 receives and stores the button signal and analyzes the content to decide the performance of the meeting halfway withdrawal service. On the other hand, the selector 7 transmits a silence pattern '0' to a time slot informed from the multi-frequecncy signal reception circuit 4. No button signal representing the meeting halfway withdrawal service is outputted to an adder circuit 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a conference trunk of an electronic exchange equipped with a function of simultaneously carrying out multiparty calls.

[Background of the invention]

2. Description of the Related Art Electronic exchanges equipped with a voice addition function have been proposed in the past in order to simultaneously carry out multi-party calls using telephone lines.

A specific example of this is described in 1, 1988 IEICE General National Conference K1652R Conference Telephone System in Digital Switching System.

FIG. 2 shows a conventional electronic exchange 10 equipped with a voice addition function.
As shown in Figure 6, which is a block diagram mainly showing the conference trunk 20 housed in the electronic exchange 10, a plurality of telephones are connected to the electronic exchange 10, and the conference trunk 20 is housed in the electronic exchange 10. The conference trunk 20 is composed of a multifrequency signal receiving circuit 4, an adding circuit 5, and a microprocessor 6.

This conference trunk 20 provides special services requested by subscribers during a conference call (for example, a mid-term service that stops transmitting one's own voice and only listens to the voices of others).
Request from the subscriber (push button signal) output from the multiplexer 3 via the interface
The multi-frequency signal receiving circuit 4 in the conference trunk 20 receives the signal. After the multi-frequency signal receiving circuit 4 receives a push button signal indicating a request from the subscriber, the microprocessor 6 causes the adding circuit 5 to perform processing in accordance with the request. That is, in the case of the above-mentioned intermediate service, processing is performed in which the requester's voice is not added.

However, in the conference trunk 20 of the conventional electronic exchange described above, when a subscriber makes a request for a special service, the push button signal is passed through the summing circuit 5 to
There is a problem in that the push button signal sound is sent to other subscribers and the other subscribers can hear the special service request push button signal sound.

[Purpose of the invention]

The present invention has been made in view of the problems of the prior art described above, and even if a subscriber requests a special service during a conference call,
The purpose is to provide a conference trunk of an electronic exchange in which the requestor of the special service cannot be heard by other subscribers.

[Summary of the invention]

The conference trunk of the electronic exchange of the present invention detects a special service request signal output from a telephone.

first means for detecting a time slot number corresponding to the telephone that outputs the special service signal; and receiving the time slot number output from the first means, and blocking the special service request signal in the time slot. and second means for transmitting an unvoiced sound pattern.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in more detail with reference to the embodiment shown in FIG. Incidentally, the same parts as those in the conventional example shown in FIG. 2 are given the same reference numerals, and the explanation thereof will be omitted.

The difference between the embodiment shown in FIG. 1 and the conventional example shown in FIG. 2 is that a selector 7 is provided in the conference trunk 20. The operation of this embodiment will be explained below. Voices from subscribers participating in the conference are converted into digital signals through the transmitter of the telephone 1 and the interface circuit 2, and are multiplexed by the multi-demultiplexer 3. The outputs of the multi-demultiplexer 3 are added together in an adder circuit 5 via a selector 7, and then transmitted to each subscriber for a conference call.

If, during a conference call, a push-button signal indicating a request for intermediate service is generated from a subscriber's telephone 1, this push-button signal is digitized and multiplexed as described above.

Thereafter, the multi-frequency signal receiving circuit 4 detects the push button signal and interrupts the microprocessor 6, and at the same time notifies the selector 7 of the time slot number corresponding to the telephone 1 from which the push button signal was output. do. Here, the detection of the time slot number is performed by a signal present register (not shown) provided in the multifrequency signal receiving circuit 4. This signal present register is a register that detects and displays the presence or absence of a push button signal for each time slot, and each bit of the signal present register corresponds to each time slot. The above-mentioned notification to the selector 7 can be performed by reading this signal present register.

The multi-frequency signal receiving circuit 4 described above works in the same way as the conventional system shown in FIG. 2, and receives and notifies push button signals.
The microprocessor 6 receives and stores the push button signal, analyzes its contents, and determines that the mid-way service will be provided. On the other hand, the selector 7 selects a silent pattern "0" without passing the input signal for the time slot notified from the multi-frequency signal receiving circuit 4.
'' is transmitted. This prevents the push button signal indicating the middle service from being output to the adder circuit 5, and prevents other subscribers in the conference from hearing the push button signal sound.

When the push-button signal indicating a request for uninterrupted service from the subscriber ends, the multi-frequency signal receiving circuit 4 detects this and notifies the selector 7 of the end of the push-button signal. Upon receiving this notification, the selector 7 stops transmitting the silent pattern ``'0'''' of the above-mentioned time slot,
The input signal is output as is to the adder circuit 5. Further, the microprocessor 6 determines that it is a middle service from the received push-button signal, and then controls the addition circuit 5 to stop the audio addition of the time slot, thereby realizing the middle service.

In the above embodiment, a delay circuit may be provided in front of the selector 7 to reliably block the push button signal requesting a special service.

It is also possible to use other specific signals indicative of special services instead of push button signals.

〔Effect of the invention〕

As described above, according to the present invention, after detecting a push button signal sent by a subscriber for a service request during a conference call,
Immediate removal allows a service request from a subscriber to be accepted without other subscribers hearing the push button signal tone.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing an example of the prior art. 1...Telephone, 2...Interface circuit, 3...
Multi-demultiplexer, 4... multi-frequency signal receiving circuit. 5... Addition circuit, 6... Microprocessor, 7.
...Selection circuit, 10...Electronic exchange, 20...Conference trunk.

Claims (1)

[Claims] A special service request signal output from a telephone is detected in a conference trunk of an electronic exchange having a function of simultaneously carrying out calls between one, three or more subscribers, and the special service request signal is a first means for detecting a time slot number corresponding to the output telephone; and receiving the time slot number output from the first means, and transmitting an unvoiced sound pattern by blocking the special service request signal in the time slot. A conference trunk of an electronic exchange, characterized in that it comprises second means. 2. Claim 1, wherein the special service request signal is comprised of a push button signal.
Conference trunk of the electronic exchange described in Section.