JPS598117B2 - Time division exchange method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a time-division switching system, and more particularly to a time-division switching system that allows network expansion from small stations to large stations to be carried out economically and easily.

A time-division electronic switching system performs telephone switching and interruption switching by exchanging individual signals sent time-division multiplexed on a single highway between arbitrary time-division time slots. An example of such a time division switch is THEBELLSYSTEMTECH.
NICALJOURNAL VOL56, /F6.7, 1
The structure shown in FIG. 1 is disclosed on page 977, page 1023.

In the figure, 1 is a trunk circuit (hereinafter referred to as TRK) that transmits and receives individual signals supplied via the audio frequency line 2, as well as transmits dial signals and line status determination signals; A codec (hereinafter referred to as C) that converts individual signals into time-division multiplexed signals
4 is a synchronization circuit (hereinafter referred to as SYNC) that transmits and receives the time division multiplexed signal supplied via the digital line 5, and separates and outputs the part containing the dial signal and line status signal. This SY
The NC 4 has a function of synchronizing the frequency and phase of the time division multiplexed signal sent via the digital line 5 with the clock of the time division exchange, and makes the time division multiplexing of the time division exchange coincide with the multiplicity of the digital line 5. It has multiplexing and demultiplexing functions. 6a and 6b are regular and backup time-division communication paths (hereinafter referred to as TDNW), and these TDNWs 6a,
6b is the CODEC via system selector switches 7A and 7b.
3 and SYNC4.

8a, 8b are TRKl, SYNC4, TDNW6a, 6
These SPCs 8a and 8b control the TRKLCODEC 3 and
Connected to TDNWs 6a and 6b.

12a and 12b are connected to the SPC via the system changeover switch 13.
8a, 8b is a regular and standby central processing unit (hereinafter referred to as CC), and this CCl2a, l2
b is configured to centrally control each part via SPCs 8a and 8b.

The time division exchange configured in this manner receives individual signals supplied via the voice line 2 through the TRKl, and from this TRKl, a dial signal identification signal and a line status determination signal are sent via the system changeover switch 9. The commonly used SPC8
supplied to a.

Also, the individual signal received by TRKl is CODE
C3, and in this CODEK3, the time division multiplicity (
(including frequency and phase matching) and then supplied to the regular TDNW 6a via the system changeover switch 7a. Here, the SPC 8a uses the dial identification signal and the line status determination signal supplied from the TRKl to
By controlling the TDNW 6a under the control of the TDNW 6a, the individual signals time-division multiplexed to each time slot are exchanged to the time slot designated by the dial signal. On the other hand, from the time division multiplexed signal supplied via the digital line 5, only the portion (time slot) containing the dial signal and line status signal is separated at the SYNC 4 and supplied to the SPC 8a.

SPC8a determines the dial signal and line status by identifying the signal supplied from SYNC4, and
By controlling the TDNW 6a under the control of Cl2a, the individual signals time-division multiplexed to each time slot are exchanged to the time slot designated by the dial signal. And TDNW6a, . SPC8a
、． If a failure occurs in any of the CCl2a,
A fault monitoring circuit (not shown) is activated and the system changeover switch 7
It is configured to switch and control the corresponding parts of A, 7b, 9, 10, and 13, and automatically switch and replace the failed part with a spare device.

Note that the above switching operation is also performed between the audio frequency line 2 and the digital line 5.

However, in the time division switch with the above configuration, the individual signals supplied via the audio frequency line 2 are transmitted and received at TRKl, and the individual signals supplied via the digital line 5 are transmitted and received at SYNC4. Because of this, the transmission and reception between the two devices and the handling of various control signals become different, resulting in complicated control procedures and an extremely large number of signal lines between each device. Therefore, if you try to increase or decrease networks in such a time-sharing switch, you will have to rewire a huge amount of control lines and change various control procedures, which is almost impossible at the field stage. I have to say it's work. In view of the above points, the present invention has been made to solve such problems and eliminate such drawbacks.The purpose of the present invention is to unitize the exchange capacity into units of a certain capacity so that it can be arbitrarily and easily increased or decreased. It is an object of the present invention to provide a time division switching system which can improve expandability and manufacturability, and which can modularize not only hardware but also software related to communication path control.

In order to achieve such an object, the present invention unifies the control system by digitally processing the transmission and reception of individual line signals input and output to and from a time-division exchange and the identification of control signals in a digital trunk. A digital trunk and a communication path control device are used as a communication path unit for each capacity, and by combining a plurality of communication path units as one block, the exchange capacity can be increased or decreased as a building block, The time-division communication paths, digital trunks, and communication path control devices that make up the time-division exchange are integrated for each scale, and each integrated unit is handled according to increases and decreases in the network scale. The number of units can be increased or decreased simply by changing the semi-fixed path of the switch unit.

Hereinafter, the time division switching system according to the present invention will be explained in detail using the drawings. FIG. 2 is a main part block diagram showing the basic configuration of the time division switching system according to the present invention. In the figure, 20a to 20n are regular communication path units (hereinafter referred to as SPUs), and 20x is a standby SPU. and each of these SP
U2Oa to 20n and 20x are unitized with a certain exchange capacity as a unit.

21 is a test unit (hereinafter referred to as TSTU) that tests SPU2Oa to 20n, 20x, 22a to 22n are each SPU
Input highway 23a and TSTU of PU2Oa~20n
Input side changeover switches (hereinafter referred to as TRF) are provided at the intersections of the maintenance input highway 24a connected from 2l to the SPU2Ox, and 25a to 25n are for each S
Output highway of PU2Oa~20n 23b, 5SPU
Output side changeover switches (hereinafter referred to as TRB) provided at each intersection with the maintenance output highway 24b connected from 20x to the TSTU 2l, 26a and 26b connect to each SPU via the junker highway 27a and 27b.
A regular and standby junction switch (hereinafter referred to as JSU) that connects 2Oa to 20n for each number of individual call signals (number of time-division time slots) as one unit, 28
is a central control unit (hereinafter referred to as CPU), and this C
The PU 28 sends control signals via the control signal highway 29 to perform overall control of each SPU 2Oa to 20n, analysis of various data at the time of failure and testing, and input/output changeover switches 22a to 22n, 25a to 25.
n switching instructions, etc.

Although the input/output highways 23a and 23b are shown as one, they are composed of a plurality of highways.
It is assumed that it is connected to CODEC3 or SYNC4 mentioned in the figure. Furthermore, in addition to the voice signal, the time-division multiplexed digital signal also includes control information necessary for exchange connection processing, such as dial signals and line status signals (for example, in empty time slots). do. In the time division switch configured in this manner, the digitized individual line signals supplied via the input highway 23a are sent to the SPUs 2Oa to 23A under the control of the CPU 28.
After spatial and temporal exchange processing is performed by the JSU 20n and the JSU 26a, the signal is supplied to a CODEC or SYNC (not shown) via an output highway 23b.

In this case, as will be described in detail later, SPU2Oa to 20n include functions to analyze and identify control signals such as dial signals and line status signals that are sent in digital form. Control for normal time-sharing exchange is performed in the JSU, and the CPU 28 controls each SP.
It is sufficient to perform overall control between U2Oa to 20n and 20x. Therefore, even if the SPU is sensitized as part of the building process, the problem can be dealt with by only slightly changing the JSUs 26a and 26b. This is because portions that analyze and process control signals such as dial signals and line status signals are distributed within each SPU. Next, when a failure occurs in the SPU 2Oa, for example, the input/output side changeover switches 22a and 25a are set so that the CPU 28 replaces the SPU 20a with the spare SPU 20x based on a failure detection signal supplied from a general failure monitoring circuit (not shown). Switching control is performed, and from then on, the spare S
Continue the replacement operation using PU20x. On the other hand, the maintenance input/output highways 24a and 24b, which were connected to the TSTU 21 to test the spare SPU 20x, are connected to the SPU 20a as the input/output changeover switches 22a and 25a switch. Therefore, TSTU21 is an SPU that has been disconnected from the main exchange operation due to the occurrence of a failure.
20a, and the test results are supplied to the CPU 28 via the control signal highway 29. The following is an explanation of the block diagram shown in Figure 2, and the following is SPU2
The inside of 0a to 20n and 20x will be explained in detail. FIG. 3 is a block diagram showing an example of the SPU 20 shown in FIG. 2, and the same parts as in FIG. 2 are designated by the same symbols and detailed explanation thereof is omitted.

In the figure, 30a and 30b are input side changeover switches 22.
and front and back time division communication channel connecting devices (hereinafter referred to as TDCs) connected to the output side changeover switch 25; 31a and 31b are time switches (hereinafter referred to as TSWs) connected to the TDCs 30a and 30b, respectively;
is the time switch TSW31a for time division exchange.
, 31b is a holding memory (hereinafter referred to as HM) that controls the storage or readout position (timing) of these TSs.
W31a, 31b. The HM 32 constitutes a time division communication device 33 (hereinafter referred to as TDS). 34a and 34b are digital trunks (hereinafter referred to as DTRK) that use digital processing technology to separate and identify control signals such as dial signals and line status signals that are multiplexed and sent to empty channels; 35 is NM32, DTRK34a; , 34b and C
A communication path control device (hereinafter referred to as SPC) 36 has an interface function between the PUs 28, receives and distributes control signals, and performs partial preprocessing if necessary. This is a janctor changeover switch (hereinafter referred to as TRJ) that performs this operation.

In the SPU 20 configured in this manner, the time-division multiplexed individual line signals supplied via the input highway 23a are transferred to the TD via the input side changeover switch 22.
It is supplied to C30a.

The TDC 30a converts this digitized individual line signal to match the timing and conditions with the standard clock of the exchange used when performing time division switching, and if necessary, to simplify the switching process in the time switch TSW 31a. Part of serial/parallel conversion and multiplicity conversion is performed. On the other hand, the DTRK 34a separates and identifies control signals such as dial signals and line status signals from the individual signals received by the TDC 30a, and supplies them to the SPC 35. The SPC 35 stores information for exchange processing in the HM 32 under the supervision of the CPU 28 (FIG. 2). H.M.
32 controls the TSW 31a based on the exchange information to exchange the time slot positions, thereby exchanging individual line signals. Note that since this TSW 31a is generally well known, detailed explanation of its configuration and operation will be omitted. On the other hand, DTRK34b is TDC30a, . TSW
31a. JSU26a (Fig. 2), TSW31b, TD
Various line individual signals from other stations are digitally received and processed via the C 30b, and the results are sent to the CPU 28 (FIG. 2) via the SPC 35. Figure 4 is 2
This figure shows the flow of interoffice line individual signals between each SPU and the JSU 26a, and the same parts as in FIGS. 2 and 3 are shown using the same symbols.

In the same figure, the broken line indicates the above-mentioned CODEC3 or SY
It shows the route of the inter-office line individual signal sent from NC4 using an empty time slot on the highway. In this case, when a line individual signal is input to the DTRK 34b via the path shown by the broken line, the DTRK 34b separates control signals such as dial signals and line status signals and sends them to the SPC.
35. The SPC 35, alone or under the control of the CPU 28, translates and identifies the control signal, and performs the exchange operation by controlling the TSWs 31a and 31b based on the results. In addition, if it is necessary to connect (exchange) a highway housed in another SPU, connect the other SPU 20a via the JSU 26a, as shown by the dashed line.
connected to. In addition, in the above explanation, SPU
Input highway 20b - Reception of inter-office line individual signal from 23a, input to SPU 20b...S from highway 23a
Although only the setting of a one-way speech path from the PU 20a to the output highway 23b has been described, it goes without saying that it is also possible to set a two-way speech path. On the other hand, the DTRK 34b generates a visit tone when the line is used.

This visit tone is JSU26a. TSW3la. T.D.
Set a fixed path in C3Oa and enter the input highway 12
By connecting up to 3a, it is possible to send out to any time slot on the output byway 23b as in the case of converting the inter-office individual signal described above using TSW 3lb. In this case, the above control operation can be processed by the SPC 35 in each SPU 20 without being controlled by the CPU 28, resulting in an improvement in the processing capacity (overall efficiency) of the CPU 28.

In addition, if the tension of the janctor between each SPU2O is set semi-fixed, the SPC35 in each SPU2O
It is possible to know what kind of junk pattern mode is currently in the SPU2O.
This makes it extremely easy to connect communication paths, send and receive signals, test, etc., making it possible to modularize both hardware and software. Therefore, when expanding the network, build up a building block structure by stacking SPU2Os according to the increase in scale as shown in Figure 2, and expansion tests can be easily performed using spare JSU26x and TSTU2l. I can do it. Furthermore, with the development of integrated circuit technology,
If the speed and size of the apparatus were to be increased, each apparatus shown in FIG. 3 could be contained in one structural unit (for example, one unit, one rack, etc.).

Therefore, in the conventional redundant configuration provided for each device, the hardware increases as redundant switching occurs between devices, but as mentioned above, redundant switching is performed for each structural unit (SPU). This also solves the above-mentioned problem. As explained above, the time-division switching system according to the present invention uses semi-fixed paths to connect junctors between units that integrate time-division channels, digital trunks, and channel control devices that make up a time-division switch. The first invention is configured so that when the scale of the network increases, the unit can be stacked like a building block. This has the effect of simplifying the expansion program, and in addition to the configuration of the first invention, the second invention has a configuration in which a backup communication path unit and a switch for backup switching are provided, so that it can be replaced in the event of a failure of the communication path unit. This has the advantage of being able to switch to a standby communication path unit without interrupting processing, resulting in a highly reliable system.

The following effects can be obtained in common with the first and second inventions. In other words, regarding the transmission and reception of individual line signals, the signal is converted and inserted into an empty time slot on the highway that inputs and outputs from the exchange using a coattech or synchronizer, and is connected to the digital trunk via a fixed path through the jack switch unit and the time-division communication path. By doing so, various excellent effects can be achieved, such as modularization of not only the hardware but also the software related to single-call control.

[Brief explanation of drawings]

Figure 1 is a block diagram showing the main parts of a conventional time division switch.
FIG. 2 is a block diagram of main parts for explaining the time division switching system according to the present invention, FIG. 3 is a block diagram showing an example of the channel unit shown in FIG. 2, and FIG. FIG. 3 is a block diagram showing signal paths. 20a to 20n, 20x... communication channel unit,
21...Test unit, 22a-22n...
...Input side selector switch, 23...Highway 1, 24...Maintenance highway 1, 25...
... Output side selector switch, 26... Junctor switch, 27... Junctor highway 1, 2
8...Central control unit, 29...Control signal highway 1, 30...Time division communication path connection device, 31...Time switch, 32... ...Holding memory, 33... Time division communication device, 34...
...Digital trunk, 35...Call route control device.

Claims (1)

[Scope of Claims] 1. In a time division exchange that exchanges time division multiplexed signals, a plurality of communication path units, a junction switch unit that connects the plurality of communication path units, and each communication path and a central control device that performs overall control of the units, and the channel unit is a time-division channel device that exchanges signals time-division multiplexed in each time slot between arbitrary time slots, and a dial signal identification device. and a digital trunk device that digitally determines line usage status, etc., a communication path control device that interfaces the time division communication path device and the digital trunk device with a central control device, and receives and distributes control signals, The time division path device, the digital trunk device, and the call path control device constituting the time division switch are integrated for each scale, and each integrated unit is handled according to increases and decreases in the network scale, and the junk A time division switching system characterized in that the number of units can be increased or decreased simply by replacing the semi-fixed bus of the switch unit. 2. In a time-division exchange that exchanges time-division multiplexed signals, there are multiple communication path units, a backup communication path unit, a junction switch unit that connects each communication path, and a junction switch unit that connects each communication path unit. Each of the communication path units includes a central control unit that performs overall control and detects the occurrence of a failure, and a changeover switch that switches the failed communication path unit to the backup communication path unit in response to the failure detection of the central control unit. is a time-division channel device that exchanges signals time-division multiplexed in each time slot between arbitrary time slots, a digital trunk device that digitally performs dial signal identification and line status determination,
The time-division channel device and the digital trunk device constitute the time-division switch, and are composed of an interface between the time-division channel device and the digital trunk device and a central control device, and a channel control device that receives and distributes control signals. and communication path control equipment for each scale,
The time sharing system is characterized in that each unit of the integrated unit is handled according to an increase or decrease in network scale, and the number of units can be increased or decreased simply by replacing the semi-fixed path of the junction switch unit. Exchange method.