JPH09139724A - Digital line multiplexer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent reduction in a multiplex gain and to decrease the number of transmission lines for a control signal by providing a monitor signal multiplex section and a monitor signal demultiplex section to a DCME so as to provide a cross connect device. SOLUTION: In an input signal from a trunk line, only a voice signal is extracted via a trunk I/F 31 and a monitor signal multiplexer section 34, and a detector 41 detects a voiced sound. The voiced sound detected via a delay circuit 42 is given to a transmission allocation processor 43 and a TX.TSI 45, which reserve a voice exclusive line, to which the voice signal is outputted. Furthermore, a monitor signal as a control signal is received via each PG channel and the monitor signal multiplexer section 34 extracts only the control signal. Then the signal is multiplexed by a cross connect function to a clear channel via a monitor signal I/F 33. Furthermore, a monitor signal demultiplexer section 35 multiplex/demultiplex input control information from the monitor signal exclusive line and returns the result to a corresponding PG.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital line multiplexer used in a system in which a voice signal and a monitor control signal coexist on the same transmission line.

[0002]

2. Description of the Related Art FIG. 4 is a communication system configuration diagram showing a communication system for mobile communication and another telecommunication network. In the figure, reference numeral 101 denotes an exchange station at a connection point with another public network or the like, through which a telephone 102, a facsimile 103 or the like connected to the public network can be communicated. On the other hand, the mobile communication network is centered on 61 exchanges and can communicate with each mobile unit 63 via the base station 62. Base station 62 of mobile communication network
And the switching center 61 or between the switching center 61 and another network switching center 1
Digital line multiplexer (DCME) 120 between 01
Is installed, the communication information with the mobile device is multiplexed, and the line is effectively used. FIG. 5 is a diagram showing a configuration of a DCME device used in an international satellite line, and this DCME device is used in the conventional mobile communication network shown in FIG. In the figure, the DCME 120 is a trunk line and the trunk interface unit 13
1 and is connected to the bearer line by a bearer interface unit 132. FIG. 6 shows a primary group (Primary G) connected to the trunk line of the DCME.
is a diagram for explaining information transmission between a group) and DCME, and between two DCMEs.

Next, the operation of information transmission using the conventional DCME will be described. In FIG. 6, the primary group (PG) is input from the base station 62, and 1.5 MbpsX1
0 or 2 Mbps x 10 PG1 to PG10
2 is connected to DCME-A 1. The trunk line 2 has control signals M13 and M2.
4, the control signal M35, and the control signal M46 are mixed with other audio signals V in each PG signal. In the configuration of FIG. 5, the audio signal V of each PG 2 is the audio detector 14
1 is used to detect sound, and TX TSI 145 detects so-called DSI (Digital Speech Interp).
processing, and the adaptive PCM coder 144
Is compressed and encoded by the transmission allocation processor 143 to allocate a line, and the bearer interface
It is output to the bearer line via the unit 132. On the contrary, the information from the bearer line is decoded by the adaptive PCM decoder 147, subjected to DSI processing by RX TSI 148, separated by the reception allocation processor 146 into the corresponding trunk line, and transmitted via the trunk interface unit 131. By this operation, only the voice signal V is compressed to 32 kbps or 24 kbps as shown in 8 of FIG. 6, but the control signal is fixedly assigned as shown in 7 and multiplexed on the same transmission line as the voice channel. .

[0004]

Since the conventional DCME is configured as described above, if voice signals and control signals coexist on the transmission line, fixed allocation is performed for the control signals, so the line utilization efficiency is improved. However, there was a problem that

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a DCME device which prevents a decrease in multiplexing gain and reduces the number of transmission lines for control signals.

[0006]

In a digital circuit multiplexer according to the present invention, a digital primary group signal in which voice and control signals are mixed is used as input / output of a plurality of systems, and a voice signal is extracted from the plurality of digital primary group signals. A voice encoding / decoding unit for compressing and encoding and outputting to the assigned line, decoding the compression-encoded input information from the assigned line to restore the voice, and a monitor signal as the assigned line. A monitor signal interface that secures a dedicated line and connects to this monitor signal dedicated line, and a monitor signal interface for the assigned line that extracts and multiplexes only predetermined control signals from digital primary group signals of multiple systems To the digital primary group signal corresponding to the monitor signal multiplexer and the input multiplex control information from the assigned line via the monitor signal interface. And a monitor signal separator back demultiplexes the respective systems.

In addition to the basic configuration, further, in a plurality of digital line multiplexers, the interface with the digital primary group signal of each device is provided as many as the number of digital line multiplexers, and the monitor signal multiplexer and the monitor signal demultiplexer are provided. One monitor signal multiplexing unit and one monitor signal demultiplexing unit are used for demultiplexing and demultiplexing all predetermined control signals in a plurality of digital primary group signal interfaces. I tried to use the line.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. In the mobile communication system shown in FIG. 4, 30 new devices are used as the digital circuit multiplexer (DCME). FIG. 1A is a diagram showing the configuration of a new DCME according to the first embodiment of the present invention, which is the DCME 30 of FIG. In FIG. 1, the PG group 2 is connected to the trunk interface from the base station 62.
It is connected to the unit 31. Further, 32 is a bearer interface unit (bearer I / F), and 33 is a monitor signal interface (I / F). A monitor signal multiplexing unit 34 extracts only the control signal and the like from the PG of the trunk line and multiplexes them. Reference numeral 35 is a monitor signal demultiplexing unit for demultiplexing the input control information from the monitor signal dedicated line and returning it to the corresponding PG. Thus, it has a so-called cross-connect function. Figure 1 (b) shows bearer I
FIG. 6 is a diagram showing a compressed and multiplexed voice code on a voice dedicated line from / F 32 and a multiplexed control signal on a monitor signal dedicated line from a monitor signal I / F 33.

Next, the operation of the DCME having the configuration shown in FIG. 1A will be described. D that combines multiple channels in order to efficiently transmit voice by applying digital voice processing technology
It is well known that SI technology is available and 40% or less of voiced voice is extracted and transmitted from a plurality of calls to improve the transmission capacity. The input signal PG 2 from the trunk line in FIG. 1 is converted into a format for internal processing by the trunk I / F 31, and only the voice signal is extracted by the monitor signal multiplexing unit, and the voice detector 41 detects voice. Will be done. The voiced sound detected via the delay circuit 42 secures a voice dedicated line by the transmission allocation processor 43 and the TX TSI 45, allocates that channel, and outputs a voice signal. Adaptation P at that time
The CM coder 44 performs compression coding to obtain a high DSI gain. With respect to the input information from the bearer line, the reverse DSI processing operates, and the reception allocation processor 46 and the adaptive PCM decoder 47 decode and demultiplex the compressed voice code and return it to each PG.

FIG. 2 is a diagram showing how the audio signal and the control signal are multiplexed when the apparatus having the configuration of FIG. 1 is used as the DCME-A of FIG. In this example, the monitor signal as the control signal is 2TS (Time Slo) for each PG channel.
t) 10, the case where the audio signal is 22TS 11 is shown. This PG input is the monitor signal multiplexing unit 34 of FIG.
By this, only the control signal is extracted. Then, as shown by 14 in FIG. 2, 64 via the monitor signal I / F 33.
It is multiplexed on the kbps clear channel by the cross-connect function. Also, the audio signal in the PG is 32 kbps after the control signal is extracted by the DSI process and the adaptive PCM process of FIG.
Alternatively, it is assigned to one channel of 24 kbps. Then, it is output to the voice-only bearer line via the bearer I / F 32, as indicated by 13 in FIG. In this way, in the opposing DCME-B, only the voice code channel needs to be connected, and the clear channel can be directly connected to the exchange 61.

Embodiment 2. In the first embodiment, DCME
Although the case where the number of DCMEs is one has been described, the control signal multiplexing and the configuration of DCME when a plurality of DCMEs 3 are opposed to each other will be described below. Specifically, in the system of FIG. 4, a plurality of base stations 62 are connected to one exchange 61 by using DCME. In this case, if a dedicated voice signal line and a dedicated control signal line such as a monitor are provided for each opposite DCME, the cost of using the transmission line increases. In such a case, the DCME connection configuration shown in FIG. 3 is used. A-1 16, A-2
Reference numeral 17 denotes the DCME of FIG. 1, but the monitor signal I / F 3
3, the monitor signal multiplexer 34, and the monitor signal separator 35 are not provided. A-318 is DCM of other A-1 and A-2.
It has a monitor signal demultiplexing unit that extracts a monitor signal as a control signal from the PG input to E and multiplexes it into one bearer line, and a monitor signal separating unit that performs the reverse operation.

The operation in this case is as follows. DC facing each voice-only bearer line 21, 22, 23
Only the voice code is transmitted to B-1, B-2, and B-3 of ME. On the other hand, all control signals are extracted by A-3 DCME, and control signals M1 to M8 and M9 to M of each TS are extracted.
16, M17 to M24 are multiplexed on the clear channel 24 and directly connected to the exchange. In this way, only one monitor control signal line is required.

In the above embodiment, the monitor signal multiplexing unit and the monitor signal separating unit are provided only in A-3 of the DCME. However, for convenience of manufacture, A-1 and A-2 are provided.
It is also possible to provide the monitor signal multiplexing unit 34 and the monitor signal demultiplexing unit 35 in all the DCMEs, and to configure only the connection relationship between them in the configuration of FIG. That is, the monitor signal I / F 33 equivalent is cascade-connected to the last A-3 DCME monitor signal I / F.
33 is connected to the monitor signal dedicated bearer line.

[0014]

As described above, according to the present invention, D
Since the CME is provided with the monitor signal multiplexing unit and the monitor signal separating unit and has the cross-connect mechanism, only the control signal can be extracted and transmitted through the dedicated line, and sufficient DSI processing can be performed for the voice transmission path. It is possible to prevent the decrease of the DCME multiplexing gain. Further, when the control signals of a plurality of DCMEs are cascaded and multiplexed, there is an effect of reducing the number of monitor signal lines.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an example of a DCME according to the present invention.

FIG. 2 is a diagram showing how an audio signal and a control signal are multiplexed when the configuration of FIG. 1 is used in one of the opposing DCMEs.

FIG. 3 is a diagram showing a connection between DCMEs facing each other and multiplexing of audio signals and control signals in the second embodiment.

FIG. 4 is a diagram showing a communication system between mobile communication and another telecommunication network.

FIG. 5 is a block diagram of a conventional DCME.

FIG. 6 is a diagram showing a state of inter-DCME connection and multiplexing of voice signals and control signals when a conventional DCME is applied to mobile communication.

[Explanation of symbols]

30 DCME, 31 Trunk Interface Unit, 32 Voice Line Interface Unit, 3
3 monitor signal line interface, 34 monitor signal multiplexing unit, 35 monitor signal separating unit.

Claims (2)

[Claims] 1. A digital primary group signal in which voice and control signals are mixed is used as input / output of a plurality of systems, a voice signal is extracted from the plurality of digital primary group signals, compression-encoded, and output to an allocation line. Of the voice coding / decoding unit that decodes the compression-encoded input information from the to restore the voice and restores it to the above multiple systems, and secures a dedicated monitor signal line as an assigned line and connects the dedicated monitor signal line. A monitor signal interface for connection, a monitor signal multiplexer for extracting only a predetermined control signal from the digital primary group signals of the plurality of systems and multiplexing the signal, and outputting the multiplexed signal to the monitor signal interface of the assigned line, Monitor signal separation unit that demultiplexes the input multiplex control information from the assigned line via the monitor signal interface into the corresponding digital primary group signals and returns them to each system And a digital line multiplexer provided with. 2. In a plurality of digital line multiplexers, the interface with the digital primary group signal of each device is provided as many as the number of digital line multiplexers, and one monitor signal multiplexer and one monitor signal separator are provided. However, all the predetermined control signals in the plurality of digital primary group signal interfaces are multiplexed and demultiplexed by the one monitor signal multiplexing unit and the monitor signal demultiplexing unit, and one monitor signal dedicated line is used. 2. The digital line multiplexer according to claim 1, wherein