JPH1127710A - Digital relay private branch exchange - Google Patents

Abstract

[PROBLEMS] To enable digital one-link control even in a signal-in-slot system, increase the number of multiplexed voices, and improve the use efficiency of the line. SOLUTION: A CPU 5 switches a switch of a 1 link switching unit 3 to a side, and voice information input from an incoming line is
Bypass the DECODER / signaling information extraction / separation unit 27. At the same time, the one-link switching unit 8 is switched to the fixed terminal a side, and the audio information bypasses the CODER / signaling multiplex insertion unit 7 through the TSW 25. Also, the CPU 5 is 1
The link switching unit 9 is switched to the fixed terminal a side. In this operation, the signaling information superimposed on the voice information independently of the voice information is converted into appropriate signaling information by the signaling information converter 9 and transmitted from the outgoing line. As a result, the audio information becomes DECODER / CODER.
, And the signaling information is controlled independently of the voice information, so that the in-slot control can be always performed at the time of the relay exchange similarly to the out-slot method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital relay private branch exchange for compressing and relaying speech in a telephone network in which a plurality of digital private branch exchanges accommodating office lines and telephones are connected.

[0002]

2. Description of the Related Art FIG. 2 is a block diagram for explaining a communication path through a voice compression circuit in a plurality of digital private branch exchanges (hereinafter simply referred to as private branch exchanges) constituting a conventional telephone network. In FIG. 2, telephone lines 33 and 34 form a communication path (communication path) through voice compression circuits 31 and 32 provided in private branch exchanges 29 and 30. Between the voice compression circuits 31 and 32, signaling information such as dial information and on / off hook information of the telephones 33 and 34 is transmitted and received while being superimposed on the voice information. Call control is performed using a so-called in-slot method. It is known that the in-slot method can use the voice band more effectively than the out-slot method in which the call control information is transmitted and received without being superimposed on the voice information.

[0003] FIG. 3 shows a 16 Kb system using an in-slot method.
FIG. 8 is a diagram illustrating a format when audio compression multiplexing is performed in ps. As shown in FIG. 3, by using the in-slot method, all compressed audio data (audio channel (ch) 1 (16 Kbps) can be stored in a normal 64 Kbps audio band.
s), audio channel (ch) 2 (16 Kbps), audio channel (ch) 3 (16 Kbps), and audio channel (ch) 4 (16 Kbps).

[0004] FIG. 4 shows the case of using an in-slot system of 16 Kb.
FIG. 14 is a diagram illustrating an example of an arrangement of signaling bits when audio compression is performed in ps. In FIG. 4, the signaling information bits S1, S2, S
3, S4 and S5 are assigned to fixed positions in the audio frame.

The signaling information (S1 to S5) of each voice compression channel shown in FIG. 3 is transmitted to the private branch exchange 2 shown in FIG.
9 and 30, the audio compression circuits 31 and 32 and the CPU 35,
Analysis processing is performed at 36, and the call control is performed.

FIG. 5 is a block diagram showing a communication path during the relay exchange. In FIG. 5, telephones 19 and 20 are connected through circuits in private branch exchanges 11, 12, and 13, and private branch exchange 12 operates as a relay.
At this time, the private branch exchange 12 for relay uses the audio compression circuits 15 and 16 in the private branch exchange 12 in order to prevent the voice quality from deteriorating by repeating compression / expansion of the voice information (signal). A detour is required. Voice compression circuit 1 built in relay private branch exchange 12
By bypassing 5, 5 and 16, voice compression / expansion is always performed by the voice compression circuits 14 and 17 of the private branch exchanges 11 and 13 of the terminal stations. That is, the digital one-link control is performed, so that the same communication quality as in non-relay can be ensured in all communication paths.

FIG. 6 is a block diagram showing a connection state of a communication path in a voice compression circuit in a private branch exchange at the time of a conventional relay. In FIG. 6, this example corresponds to a decoder (DEC)
ODER) audio compression circuit 21 and a coder (COD).
ER) -side audio compression circuit 22, DECODER / signaling information extraction / separation unit 23, 1-link switching unit 24,
28, a communication channel time switch (TSW) 25, a control CPU 26, and a coder / signaling information multiplex insertion unit 27. Here, it is necessary to perform digital one-link control in order to secure communication quality at the time of relay exchange. The CPU 26 switches the switch of the one-link switching unit 24 to the fixed terminal a side, and the voice information input from the incoming line is DECODER. / Bypass the signaling information extraction / separation unit 23. At the same time, the CPU 26 switches the one-link switching unit 28 to the fixed terminal a side, so that the voice information is transmitted through the communication path time switch (TSW) 25.
The packet is sent to the outgoing line by bypassing the DER / signaling information multiplex insertion unit 27. With this operation, the call path of the transit switching unit is connected to a call path for performing digital 1 link control that bypasses the DECODER / signaling information extraction / separation unit 23 and the CODER / signaling information multiplex insertion unit 27 of the voice compression circuit.

[0008]

However, in the above-mentioned conventional example, the voice information is converted to the DECO during the digital one-link control.
When detouring from the DER / signaling extraction / demultiplexing unit and the CODER / signalling multiplex insertion unit, the signaling extraction / multiplex insertion unit is also bypassed at the same time. No information can be obtained. For this reason, there is a disadvantage that an undefined state such as a line hold-off occurs and digital one-link control by the signal-in-slot method cannot be performed.

The present invention solves the above-mentioned problems in the prior art, and enables digital one-link control even in a signal-in-slot system, increases the number of multiplexed voices, and increases the use of the line. An object of the present invention is to provide an excellent digital relay private branch exchange that can improve efficiency.

[0010]

SUMMARY OF THE INVENTION In order to solve this problem, a digital private branch exchange according to the present invention comprises a conversion means for converting signaling information at the time of relay switching, and performs digital one-link control by an in-slot method at the time of relay switching. Is possible. Therefore, the relay private branch exchange sends predetermined appropriate control signaling information to the other private branch exchange in accordance with the terminal status information obtained from one private branch exchange independently of the voice information path. And the number of multiplexed voices increases, thereby improving the efficiency of use of the line.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A digital relay private branch exchange according to the present invention comprises an in-slot type voice compression / expansion means for superimposing signaling information used for call control on voice information, and a monitor for monitoring the signaling information. Means,
A relay exchange / conversion means for performing a relay exchange process and converting signaling information at the time of the relay exchange, and independently of a voice information path in a private branch exchange for relay, a terminal status obtained from one private exchange. In response to this information, appropriate control signaling information is sent to the other private branch exchange, and digital one-link control is possible even in the signal-in-slot method, so that voice multiplexing increases and line use efficiency improves.

Next, an embodiment of a digital relay private branch exchange according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of a digital relay private branch exchange according to the present invention. In FIG. 1, this example shows a state of connection of a voice path of a voice compression circuit in a digital relay private branch exchange. The voice compression circuit 1 on the DECODER side, the voice compression circuit 6 on the CODER side, and D
ECODER / signaling information extraction / separation unit 27, 1
Link switching units 3, 8, and 10 are provided. In this example, the communication channel time switch 4 and the control CPU 5
And a CODER / signaling multiplex insertion unit 7 and a signaling information conversion unit 9.

Next, the operation of this embodiment will be described. Digital 1 to ensure call quality during relay exchange
In order to perform link control, the CPU 5 switches the switch of the one link switching unit 3 to the fixed terminal a. Therefore, the voice information input from the incoming line bypasses the DECODER / signaling information extraction / separation unit 27. At the same time CPU
5 switches the one-link switching unit 8 to the fixed terminal a side, so that the voice information is changed to a call path time switch (TSW).
25 bypasses the CODER / signaling multiplex insertion unit 7. Further, the CPU 5 switches the switch of the 1 link switching unit 9 to the fixed terminal a side.

By this operation, the signaling information superimposed on the voice information independently of the voice information is converted into predetermined appropriate signaling information through the signaling information converter 9 and transmitted from the outgoing line.

The contents of the signaling information to be converted by the signaling information conversion unit 9 are determined by the CPU 5 to be appropriate based on the terminal state information or the partner station information detected by the DECODER / signaling information extraction / separation unit 27. You.

As described above, according to this embodiment, the audio information is bypassed by the DECODER / signaling information extraction / separation unit 27 and the CODER / signaling multiplex insertion unit 7, and the signaling information is independent of the audio information. Therefore, it is possible to always use the in-slot method as well as the out-slot method at the time of the relay exchange, since the control is performed by the private branch exchange for relay. That is, even in the signal-in-slot method, digital one-link control becomes possible, voice multiplexing increases, and the use efficiency of the line improves.

[0018]

As described above, according to the digital relay private branch exchange of the present invention, the signaling information is converted at the time of relay switching, and the digital one-link control can be performed by using the in-slot method at the time of relay switching. Independently of the voice information path, appropriate control signaling information can be sent to the other private branch exchange according to the terminal status information obtained from one private branch exchange. As a result, the number of multiplexed voices increases, and the use efficiency of the line improves.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the configuration of a digital relay private branch exchange according to the present invention.

FIG. 2 is a block diagram for explaining a communication path through a voice compression circuit in a plurality of conventional private branch exchanges.

FIG. 3 is an explanatory diagram showing a format when audio compression multiplexing is performed using an in-slot method in a conventional example.

FIG. 4 is an explanatory diagram showing an example of the arrangement of signaling bits when voice compression is performed using an in-slot method in a conventional example.

FIG. 5 is a block diagram showing a communication path at the time of relay exchange in a conventional example.

FIG. 6 is a block diagram showing a connection state of a communication path in a voice compression circuit in a private branch exchange at the time of a conventional relay;

[Explanation of symbols]

 Reference Signs List 1 voice compression circuit 2 DECODER / signaling information extraction / separation unit 3, 8, 10 1 link switching unit 4 speech channel time switch 5 CPU 6 speech compression circuit 7 CODER / signaling information multiplex insertion unit 9 signaling information conversion unit 25 speech channel time switch (TSW)

Claims (2)

[Claims] A digital relay private branch exchange in a telephone network to which at least one, the other and a relay private branch exchange are connected, independently of a voice information path, a terminal state obtained from one of the private branch exchanges. A digital relay private branch exchange apparatus for transmitting predetermined control signaling information to another private branch exchange apparatus according to the information. 2. An in-slot type voice compression / expansion means for superimposing signaling information used for call control on voice information, a monitoring means for monitoring signaling information, performing a relay switching process and converting the signaling information during the relay switching. A digital relay private branch exchange, comprising: