JPS6119159B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the signal control method of a time division concentrator used in a time division switching system, such as a PCM time division switching system.

FIG. 4 shows a conventional example of a PCM time-division telephone switching system, in which 1 is a time-division concentrator;
2-1 to 2-n are subscriber circuits, 3 is a multiplexer, 4 is a demultiplexer, 5-1 and 5-2
are an up highway and a down highway, respectively, 6 is a time division communication path device, 7 is a communication path control device, 8 is a central processing unit, 9 is a concentrator control memory, 1
0 indicates a signal processing device. The signal processing device 10 monitors the status of the subscriber circuits 2-1 to 2-n and reports status changes and dial signals to the central processing unit 8. Based on instructions from the central processing unit, the signal processing unit 10 monitors the status of the subscriber circuits 2-1 to 2-n. It supplies various control signals to 1 to 2-n. The communication path control device 7 controls the time division multiplexing gates in the time division communication path device 6 based on instructions from the central processing unit 8 . The line concentration control memory 9 has a plurality of addresses corresponding to the time slots of the time division multiplexed highways 5-1 and 5-2, and each address has a plurality of addresses corresponding to the time slots of the time division multiplexed highways 5-1 and 5-2. , 5-2, the line number to be connected is written. This line number is sent from the central processing unit 8 via the communication path control device 7.

In the conventional time-division switching system as shown in Fig. 4, in addition to the line concentration function that allocates time slots on the time-division multiplex highway to each line, the time-division concentrator also functions as a collection and distribution mechanism for the monitoring and control signals of each line. There are disadvantages in that it needs to be installed in the device, making the control interface complicated and uneconomical. In addition, the conventional method shown in Figure 4 has disadvantages such as the economic capacity of the time division concentrator is limited by the processing capacity of the signal processing device, the expansion unit cannot be arbitrarily selected, and it is not very flexible. have.

The present invention eliminates the above-mentioned drawbacks, and eliminates the need for installing an independent collection and distribution mechanism for collecting and distributing supervisory control signals in a time division concentrator, and simplifies the control interface. It is an object of the present invention to provide a signal control method for a time-division concentrator, which has features such as being able to reduce the unit of time-division concentrator expansion and manufacturing the time-division concentrator at low cost. Therefore, the signal control method of the time-division concentrator of the present invention is provided with a plurality of line correspondence units and a communication route designation memory, and the communication channel of the time division multiplex highway is controlled by the line correspondence unit designated by the communication route designation memory. In the time division concentrator assigned to the time division multiplex highway, the specific channel on the time division multiplex highway is used as a control channel for transmitting and receiving line monitoring control signals, and the communication route designation memory is used to determine the line correspondence to which the control channel is assigned. This feature is characterized by specifying the section.
Hereinafter, the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG.
The figure is a time chart explaining the operation.
In FIG. 1, 11-1 to 11-n are line corresponding parts, 12-1 to 12-n are subscriber circuits,
13-1 to 13-n are selectors, 14 is a line number decoder, 15 is a line concentration control memory, 16 is a signal add/drop circuit, 17 is a signal processing device, 18-1
18-2 indicate an up highway and a down highway, respectively.

In the one of FIG. 1, a multiplexer 3 and a demultiplexer 4 as shown in FIG.
is not provided, and instead, each line corresponding section 1
Selector 13-1...13-n for 1-1, 11-n
is provided. Further, the signal processing device 17
The highway 18- via the signal drop/add circuit 16
Connected to 1, 18-2. Line concentration control memory 15
has a plurality of numbers corresponding to the time slots of highways 18-1 and 18-2. The line number to be written to each address is instructed by a central processing unit (not shown).

As shown in FIG. 2, one frame has m time slots. For audio data, 1
The frame period is 125 μs. As mentioned earlier, in the first time slot, the line concentration control memory 1
5 is read out, and in the second time slot, the second address of line concentration control memory 15 is read out.
The same applies hereafter. As shown in the figure, when the line number #i is written in the first address, the digital audio data output from the line corresponding section 11-i at the first time slot is placed on the highway 18-1, Further, digital audio data on the highway 18-2 is taken into the line corresponding section 11-i. When the line number #n is written in the m-th address, digital voice data is transmitted and received between the line corresponding section 11-n and the highways 18-1 and 18-2 at the m-th time slot. .
In the case of the PCM system, sampling values of analog audio data are converted to digital audio data (code) of 8-bit configuration, and one digital audio code is entered into one time slot. Since nothing is written in the second address, third address, etc., the second time slot, third time slot, etc. are idle communication channels.

The Ti-th time slot is assigned as a control channel for transmitting and receiving line supervisory control signals. In the illustrated example, since the line number #1 is written in the Ti address of the line concentration control memory 15, monitoring control is performed on the line corresponding section 11-1.

The line number in the line concentration control memory 15 is decoded by the decoder 14, and a line designation enable signal is supplied to the corresponding line correspondence section 11-1 or...11-n. Now, if the line corresponding section 11-1 is specified in the first time slot, the selector 12-1 selects the audio data line 19. Thereby, voice data is transmitted and received between the subscriber circuit 12-1 and the highways 18-1 and 18-2.

In the Ti-th time slot, the signal processing device 17 puts a control signal on the down highway 18-2, and also takes in the status monitoring signal and dial signal on the up highway 18-1. Now, as shown in FIG. 2, if the line corresponding section 11-1 is specified in the Ti-th time slot, the selector 13-1 selects the supervisory control signal line 20. As a result, the control signal on the down highway 18-2 sent from the signal processing device 17 is transmitted to the subscriber circuit 12-2.
1, and in response to the control signal, status information of the subscriber circuit 12-1 and the like are sent to the signal processing device 17 via the corresponding #CTL channel on the up highway 18-1. For example, if the control signal specifies a loop detector, the state of the loop detector is reported to signal processing device 17, and if the control signal specifies a ringing relay, the ringing relay is energized; A ringing signal is sent to the subscriber line.

For example, if you allocate 64K band to PCM1 channel, then 8K (125μ
s) It is possible to send and receive supervisory control information at regular intervals, and
The method of assigning meaning to each frame is simple, and includes control data and data in 8 bits. For example, 2 to indicate control information.
bit, 2 bits as order, 4 as data
Use bits. Although it is possible to give meaning to multiple frames, in this case, it is necessary for the signal processing device 17 to perform multi-frame synchronization processing.

FIG. 3 shows a second embodiment of the present invention, in which 15' is a line concentration control memory, 17' is a signal processing device, 18-1' and 18-2' are highways, and 21 is a time-division communication path. Each device is shown. In addition,
The same reference numerals as in FIG. 1 indicate the same parts. In the embodiment shown in FIG. 3, a B/I bit is added to each address of the line concentration control memory 15'. The B/I bit indicates whether the time slot corresponding to that address is an idle talk channel or busy. The embodiment of FIG. 3 also uses an idle talk channel as a control channel. This makes it possible to change the monitoring cycle depending on the capacity of the idle line, or to shorten the monitoring cycle of the selection signal, ie, the dial pulse, in the setup phase. In the FIG. 3 embodiment, multiple highways 18-1, 18-2
The specific channel of
1', 18-2', this highway 18-
A signal processing device 17' is connected to terminals 1' and 18-2' to perform centralized signal processing.

As is clear from the above description, according to the present invention, there is no need to provide an independent collection and distribution mechanism for collecting and distributing supervisory control signals in the time division line concentrator, the unit of expansion becomes smaller, and the control interface Effects such as being able to simplify the process can be obtained. Further, according to the present invention, the common part of the time division line concentrator can be distributed to correspond to lines and the functions of the line corresponding parts can be combined, thereby achieving economicalization. In the past, this direction of functional dispersion was not economical as the amount of gold increased due to split losses. However, with recent advances in LSI technology, economicalization can be easily achieved by, for example, integrating the above-mentioned combined functions on the same LSI.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG.
The figure is a time chart explaining the operation, Figure 3 is a block diagram of the second embodiment of the present invention, and Figure 4 is a
1 is a block diagram of a conventional example of a PCM time-division telephone switching system. 11-1 to 11-n...Line support section, 12-
1 to 12-n... subscriber circuit, 13-1 to 13-n... selector, 14... line number decoder,
15... Line concentration control memory, 16... Signal branch/add circuit, 17... Signal processing device, 18-1 and 18-2...
Highway, 15'... line control memory, 17'... signal processing device, 18-1' and 18-2'... highway, 21... time division communication path device.

Claims (1)

[Scope of Claims] 1. A time division concentrator comprising a plurality of line correspondence units and a communication path specification memory, which allocates a communication channel of a time division multiplexed highway to a line correspondence unit designated by the communication path specification memory, A specific channel on the time division multiplex highway is used as a control channel for transmitting and receiving line monitoring control signals, and the communication path designation memory is used to specify a line corresponding part to which the control channel is assigned. Signal control method for time division concentrator. 2. A signal control system for a time division concentrator according to claim 1, characterized in that an unused communication channel on a time division multiplex highway is also used as a control channel.