JPS6243946A - Test signal transmitter and receiver of time division channel - Google Patents

Abstract

PURPOSE:To obtain a test signal transmitter/receiver for a time division channel with a compact constitution by providing the 1st selection information selecting a highway to insert a test data and the 2nd selection information selecting highway to extract the test data. CONSTITUTION:The test signal of the time division channel is extracted from a time division connector TDC to a channel test equipment SPTE by selecting either a forward highway or a backward highway. Further the test signal is inserted from the time division connector TDC to the time division channel by selecting either the forward highway or the backward highway. Then the circuit relating to the test data transmission/reception of the time division connector TDC is simplified, the quantity of cables for transmitting/receiving a signal is reduced and the installation space is less.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a time division switching system, more specifically, to a time division switching system and a communication path testing device for testing a time division switching system. This relates to a device that transmits and receives test signals between

(Prior art) For example, 11 published by the Telecommunications Mutual Aid Association (Foundation) [D70 type rotary exchange a [11] J pages 69-81 (Showa 58 Bet)
describes a speech path (SP) bus control device for a 070 type automatic switch. Traditionally, time division, space division,
There is a system that connects to a highway switch network with a time division communication path (TST) configuration via a time division connector device (DC).

In this conventional device configuration, the time-division connector device and the channel test device each insert a test data signal into the time-division forward highway from the digital synchronous terminal device of the time-division switching system, and also insert the test data signal into the time-division forward highway from the digital synchronous terminal device of the time-division switching system. It is divided into a functional unit that extracts the signal, and a functional unit that inserts the test data signal into the time-divided backward highway to the digital terminal station equipment and extracts the test data signal from this. .

For example, the insertion and extraction of test data signals in the forward highway is performed by the forward highway digital interface device, the forward test signal insertion TlI.
Various forward side circuits such as a C select circuit, a forward network decoder circuit, a forward test highway select circuit and a mode decoder circuit are used from the maintenance switch and test mode deployment circuits.

Insertion and extraction of test data signals on the backward highway are performed using a backward highway digital interface device, a backward test signal insertion TD.
C selection circuit, backward network decoder circuit,
Backward testing is performed from the maintenance switch and test mode deployment circuits using various backward side circuits such as highway selection circuits and mode decoder circuits.

In this conventional example, there are four modes: a normal mode in which the line under test is not pulled in, an online test mode in which the standby side is tested, an online test mode in which the active side is tested, and a meeting test mode in which the line is opened. mode can be taken. In these modes, a call path test is performed using each associated circuit element.

(Problem to be Solved by the Invention) However, not all of these test modes are always related to circuit elements in each part of the device;
Only some of the elements on the forward and backward sides are related; therefore, the device configuration is complex and has many circuit elements, compared to the functionality of the device, and the wiring for signal transmission and reception between the devices is complicated. The cable has a lot of wrinkles, and therefore the entire device takes up a lot of space, making it impossible to realize a compact device.

The present invention overcomes these drawbacks of the prior art.

It is an object of the present invention to provide a test signal transmitting/receiving device for a time-division communication path with a compact configuration.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a communication path testing means for testing a time-division communication path including a plurality of forward highways and bankward highways, and a communication path testing means. Time to connect to 11 minutes - 9 communication path: 1 connector F
Test No. 41 of a time-division communication path with four steps, in which the communication path testing means includes first selection information for selecting a highway into which test data is to be inserted from among a plurality of forward highways and packward highways; second selection information for selecting the highway from which test data is to be extracted, and the test data to the time-sharing connector stage; receiving, selecting and inserting means for selecting a highway corresponding to the first selection information and inserting test data therein; and receiving second selection information from the communication route testing means;
Selecting and extracting means selects a corresponding highway in accordance with the second selection information, extracts test data from the highway, and sends it to the eight communication route test stations.

(Function) According to the present invention, the time-division connection data of the time-division communication path is inserted into the time-division communication path by receiving the selection information of 0'S1 from the communication path test stage F, and forwarding accordingly. Choose either Highway or Bankward Highway. In addition, the test data is extracted to the communication path test means by receiving the second selection information from the communication path test means and selecting forward highway or puncture word high (example) according to the second selection information. 1j1A, an embodiment of a test signal transmitting/receiving device for a time-division communication channel according to the present invention will be described in detail.

With reference to FIGS. 1A and 1B, a particular embodiment of the present invention is advantageously applied, for example, to a time-sharing telephone switching system and comprises a time-sharing connector device TDC and a channel testing device 5PTE. In this embodiment, 16 time-sharing connector devices TDC can be accommodated in 5PTE. The devices are connected by cables that transmit signals as shown in the figure.

The time-division connector device TDC consists of eight time-division multiplex forward highways FHWO to FHW7. Duplexed time-division digital switch networks TDNWO and T
DNwI, and 8 time-division multiplexed backward highways BHIilO to BHW7 and 1 communication path test device 5
This is a device that interfaces with the PTE.

Forward highways FHWO to FH17 are time-division multiplexed highways from digital synchronous terminal equipment in a time-division switching system. Time-division digital switch networks TDNWQ and TDNIII are
It is a time-division digital switch network with a space-division and time-division channel (TST) configuration, and an active (A
CT) side and standby (SBY) side. Backward Highway 811 W O ~ B) 117
is the time division multiplexed highway to the digital synchronous terminal equipment.

In each of these highways, in this embodiment, an l frame consists of 128 time slots, and an l time slot consists of 8 serial bits. Therefore, one frame has 1024 bits.

The time division connector device TDC includes a receiving circuit RFC, a transmitting circuit SND, interface circuits CD and CR,
The network selection circuit N5EL, the test 1) insertion circuit INs, and the test highway selection circuit S[! It consists of a LO and a test mode control circuit CTL.

The receiving circuit RED receives the forward highway Fowo~FHW? from the digital synchronous terminal equipment. This is a circuit that receives the information, and is designed to support forward highways. The transmitting circuit SND is a transmitting circuit that transmits the backward highways BHWO to BHW7 to the digital synchronous terminal device, and is provided to support the backward highway.

Interface circuits CD and CR connect to network T
This is a circuit that interfaces with the DNWO and TDNWI, and is provided for each switch network. The network selection circuit N5EL selects the network TD
This is a selection circuit that selects NWO or TDNWI, and is provided for each set of switch networks.

The test signal insertion circuit INS is a circuit that inserts various insertion test data signals CIDT from the communication path test equipment 5PTE into the way under test. They are located on each highway.

The test highway selection circuit 5ELO is connected to the communication route test device i.
Selection signal C1 from 5PTE]SE,! l-NO[l
E Select the highway to be tested from among the forward highway, standby side backward highway, or active side backward highway according to the DEC conditions, extract the extracted test data signal CDDT from the selected highway, and use the communication path test device t. 5PTH
This is a circuit that outputs to.

The test mode control circuit CTL is a circuit that selects the highway under test and timing according to the test mode, that is, selects the insertion circuit INS into which the insertion test data signal CIDT is to be inserted, and the network decoder circuit DEC
It consists of O1 and a mode decoder MODEDEC. The network decoder circuit DECO is the communication path test equipment i
The insertion circuit INS to which the insertion test data signal CIDT is to be inserted is selected in accordance with the test signal insertion circuit selection signal Cl5E from 5PTE, and the timing designation signal C15E is selected.
By specifying the insertion timing with IEN,
This circuit selects the highway into which the test signal is inserted.

The ODE DEC is the mode decoder, and the communication path test equipment 5
Mode designation signal 1l that designates the test mode from PTE
This circuit switches the highway by selecting a test mode according to the lO port E and selecting one of the test signal insertion circuits INS.

- On the other hand, the communication path testing device 5PTE accesses any time slot of the multiplexed highway of the time-division communication path, inserts and extracts signals from the time-division connector device DC, and thereby It has functions such as reproducing failures of various devices and checking after failure recovery. In this embodiment, this interfaces a maximum of 16 time-sharing connector devices MTDC and maintenance equipment, and includes a maintenance equipment interface circuit INF, a test mode deployment circuit CTL FF, a common highway digital interface equipment 1cDIE, It consists of a maintenance switch MSW and a test signal insertion TDC selection circuit port EC1.

The maintenance equipment interface circuit INF is a circuit that interfaces with the maintenance equipment 2 of the time division telephone exchange system 1 to which this equipment is applied, for example, through a bus from the central processing system, and is used to perform tests. Time division connector device i receives test information such as TDC number, highway number, time slot number and test mode from the central control system of the system in the form of data words.

The maintenance switch MSW also receives test information in the form of data words from the central control system of the system, including an inserted test data signal C1, and also receives test information including an extracted test data signal from the common highway digital interface device 1cDIE. It is a switch circuit that sends the resulting information to the central control system in the form of data words.

The test mode development circuit CTL FF consists of a group of flip-flops to which the received test information is set, and develops various test information including signals CD5E, Cl5E, MODE, etc., to time-sharing the highway under test. Connector unit 71 Distributes control signals to TDC.

This is a circuit that controls each part.

Common Highway Digital Interface Device CDI
F is the divided connector unit under test W1 selection circuit SEL 1
The 0 selection circuit SEL1, which consists of
Select the time-sharing connector device to be tested from C.
Extraction test data signal CDI in tight slot of a
) is a selection circuit that extracts T and outputs it to the interface circuit INF through the maintenance switch NSW. In addition, the insertion test data signal CIDT is sent from the maintenance switch XSW to the insertion circuit INS through the digital interface circuit.
It will be sent to IH.

Digital interface circuit DI is maintenance switch M
The test mode expansion circuit CTL transmits and receives the insertion test data signal CIIIT to the time-sharing connector device TDC and the extraction test data signal CDDT from the time-sharing connector device TDC to and from the SId.
This is a switching circuit that switches according to the set state of the FF. That is, the insertion test data signal CIDT to the time division highway is sent from the maintenance switch MS- to the time division connector device TDC, and the extraction test data signal crlD from the time division highway is sent to the time division connector device TDC.
From maintenance switches to SWs, each is divided according to the amount of digital interface circuitry.

The test signal insertion TDC selection circuit DECI is a selection circuit that selects a time division connector device to be tested from among the 16 time division connector devices fl't TDCs. This selection is made by the time division connector number set in the test mode expansion circuit CTL FF.

The test mode in this device includes the following 4114 types, namely ? There are closed state (mode O), offline test mode, online test mode and encounter test mode.

First of all, under normal conditions, the communication line equipment is in normal operation and A4J,
Common Highway Digital Interface Device cDI
This is a state in which E does not pull in the line under test.

The offline test mode is a test mode for the communication line equipment in the Y-Y or failure state, and the standby ((SBY) side switch network ↑DN- instruction and this mode are specified from the communication control common control device. By doing this, one tight slot is drawn in from the highway of the standby communication path in the current operating state, the forward insertion test data signal FID↑ is inserted at the forward highway FHW, and the backward extraction test is performed using the packword highway 81 (W). The data signal I BDDT is extracted.In this case, the forward extraction test data signal FDDT of the forward highway FHW is not extracted, and the packed word insertion test data signal old DT of the backward highway BMW is not inserted.

The online test mode is an active (ACT) network test mode, and there are modes (2) and (2).In these modes, the signal FD from the forward highway FHW transmission side is
Extract DT and signal B to Packward Highway BHW
IIIT can be inserted. In addition, No. 41 is inserted into the exchange side at the forward highway FHW, and it can be extracted from the exchange side at the packward highway BHW via the network 7 port Nw.

The meeting test mode is a mode that is applied to the meeting test for line opening, and can draw in 2JI type time slots, which are the time slots under test and the time slots for meetings. In this mode, forward highway F)
It is possible to extract the signal FDDT from the transmission side with 1w and insert the signal BIDT into the transmission line side with the packed word highway BHW. Furthermore, Forward Highway FHW
Insertion of the signal FIDT into the exchange side at , and extraction IH of the signal BDDT at the packed word highway BHW are not performed in this embodiment.

When testing a time division communication path, the communication path test device 5PT
A control signal indicating test information such as the number, highway number, time slot number and test mode of the time-sharing connector device TDC that executes the test is sent to H from the maintenance device, and this is transmitted to the test mode deployment circuit through the interface circuit INF. Set to CTL FF. Therefore, a test-safe control signal is sent to the time division connector device TDC in which the test mode development circuit CTL FF accommodates the highway under test, and the time division communication path is tested.

Therefore, first, the test mode signal MODE is transmitted from the test mode development control circuit CTL FF to the time division connector device 1'l.
It is sent to the mode decoder MODE DEC of the test mode control circuit CTL of Tl)C, and is sent to the mode decoder '14.
Decoded by 0-bit E DEC. Highway switching control is performed based on this decoding result. Also, the number of the time division connector device TDC under test is changed from the test mode development circuit CTL FF of the communication path test device 5PTE to the test signal insertion T
It is set in the DC selection circuit DEC1, and the time division connector device under test lTIIC is selected.

Next, the operation of inserting and extracting test signals into and from the time-sharing connector device TUG will be explained. The test data signal C1 to be inserted is connected from the maintenance device to the interface circuit I.
It is set to the maintenance switch MSW through NF. In order to insert the insertion test data signal CIDT, the digital interface circuit DI is switched to the test data signal insertion state by the selection signal CD5H from the test mode expansion circuit CTL FF.

Note that, as described later, the insertion test data signal CIDT consists of a forward insertion test data signal FID↑ and a backward insertion test data signal BIDT.

In addition, the insertion highway selection signal Cl5E corresponds to the highway number set in the test mode development circuit CTL FF.
is transferred to the network decoder circuit DECO of the time division connector device 1T port C, and the test signal insertion circuit INS is selected. Also, at the timing according to the time slot number set in the test mode expansion circuit CTL FF,
A signal CIEN is outputted to the network decoder circuit port ECO of the time division connector device TrJC developed by the test signal insertion TDG selection circuit DEC1 according to the TDC number to be tested. This allows the network decoder circuit DEC
:0 is activated, and the insertion circuit INS into which the insertion test data signal CIDT is to be inserted, that is, the time-division highway under test, is selected.

At the same time, in order to extract the extracted test data signal CDDT, the test mode expansion circuit CTL FF sends the selection signal CD5E corresponding to the same TDC number to the test highway selection circuit 5ELO, and selects the highway from which the extracted test data signal CDDT is to be extracted. select. In addition, in order to extract the test data signal CDD, the test mode development circuit CT
The selection signal CD5E from the LFF switches the digital interface circuit OLD to the test data signal extraction state. As a result, the extracted test data signal CDDT is transferred to the highway under test selection circuit 5ELO and the under test TDC.
It is extracted by the selection circuit SEL1 and set to the maintenance switch NSW through the digital interface circuit DI. This is later read into the central processing system through the interface circuit INF.

Note that the extracted test data signal CDDT is composed of a forward extracted test data signal FDDT and a backward extracted test data signal as described later.

These forward extraction test data signal FDDT and backward extraction test data signal BDDT, including the forward insertion test data signal FIDT and the backward insertion test data signal BI[IT, are connected to the common highway digital interface device PtcDIR and the time division connector device. Transmitted and received between @TWIG.

For example, if offline mode is specified.

In order to insert the forward insertion test data signal FIDT, the standby side insertion circuit INS is selected.

In addition, in order to extract the backward extraction test data signal B port DT on the standby side, the test highway selection circuit 5E
LO is a forward extraction test data signal FDOf and a backward extraction test data signal BOOT on the standby side.
And the standby side backward extraction test data signal BDDT is selected from among the active side backward extraction test data signal BDDT.

When online mode (1) is designated, the standby side and active side insertion circuits INS are selected for insertion of the forward insertion test data signal FIDT. At the same time, in order to extract the backward extraction test data signal BDDT on the active side, the test highway selection circuit 5ELO selects the backward extraction test data signal BOOT on the active side.

When the online mode (2) is designated, the test highway selection circuit 5ELO selects the forward extraction test data signal 1.
In order to extract 5FDDT, the forward extraction test data signal FRoroT is selected, and in order to insert the packed word insertion test data signal old DT, the backward insertion circuit INS is selected.

When the encounter test mode is specified, the same highway as the online mode specification (2)! +lJ change is performed by the motor chicotor MODE DEC.

The forward extraction 1t+test data signal FDDT is extracted as follows. Test mode deployment circuit CTL
TDCJ number and highway number are set to FF,
The time division connector device TDC and the highway are selected by the upcoming drop highway selection signal CD5E. In the test highway selection circuit 5ELO of the selected time-sharing connector device TDC, the signal CD5E is ANDed with the decoding result in the mote coder MODE DEC. This allows forward extraction test data transmission1)
One forward highway FH for extraction of FDDT
W is selected. Along with this, the communication path test equipment 2!1S
The time-sharing connector device IITDC to be tested is selected by the TDC selection circuit SEL I of the PTE, which is backward extracted through the digital interface circuit.Extraction of the six test data signals DT is performed in the same manner as follows. It will be done. TDC4 and highway number t) are set in the test mode expansion circuit CTL FF, and the time division connector f is set by the drop highway selection signal CD5H from now on.
i TDC and highway selected 0 selected time sharing connector device TDC test highway selection circuit 5
At ELO, signal CD5E and mode decoder MODE D
A logical score is taken with the decoding result in the EC. As a result, one backward highway BHIII is selected for extracting the backward extraction test data signal BDDT. At the same time, the TDC selection circuit under test 5ELI of the communication path test device 5PTH
! 1TDC is selected and is accommodated in the maintenance switch MSW through the digital interface circuit DI.

Insertion of the forward insertion test data signal FIDT is performed as follows. Test mode deployment circuit CTL FF
The TDC number and highway number are set in , and the TDC and highway of the time division connector device 1 are selected by the insert highway selection signal Cl5E from now on. Along with this, insert enable signal CIE
H specifies the insertion time slot. The forward insertion test data signal FIDT is inputted from the maintenance switch MSW through the digital interface circuit to the insertion circuit INS of each time division connector device TDC. It is inserted into the forward highway FHW by the AND condition of the test mode condition and the insertion enable signal from the network decoder DECO.

The insertion enable signal sent from the network decoder circuit DECO is designated as the insertion highway by the highway #1) from the test mode development circuit CTLFF.
And on test () insert signal C from TDC selection circuit DEC1
It is sent under the logical AND condition that IEN is output. The test signal insertion TDC selection circuit DEC1 receives + and the time slot number in TDC# from the test mode expansion circuit CTL FF, and sends the signal CIEN to the time division connector device under test TDC at the time position of the designated time slot. .

To insert the backward insertion test data signal BIDT, the DO number and highway number are set in the test mode development circuit CTL FF, and the time division connector installation @ TD is performed by the future insert highway selection signal Cl5H.
C and Highway are selected. At the same time, an insertion time slot is designated by the insert enable signal CIEH. The subsequent control operation is similar to the insertion operation of the forward insertion test data signal BID described above.

Incidentally, for comparison, FIGS. 2A and 2B show an example of a test signal transmitting/receiving device according to the prior art.

As you will see, the time-sharing connector device 5PTE and the forward highway F
a part for inserting the inserted test data signal FEDT into the HM and extracting the extracted test data signal FDDT from the inserted test data signal FDDT;
Backward highway B) Insert the insertion test data signal BID↑ into Iw, and extract the test data signal B from this
It is divided into a part for extracting D[]d. These parts are designated in this figure by the reference numerals of the corresponding elements shown in FIGS. 1A and 1B, and on the forward side by the reference numerals "".
"F" and "B" are added on the backward side.The other parts are configured substantially the same as the corresponding parts of the embodiment of the present invention described above. There is.

For example, insertion of the insertion test data signal FIDT into the active side forward highway is performed using 0 [IE DEC in the forward highway digital interface device FDIE, the forward test signal insertion TDC selection circuit FDECI, the forward network decoder circuit FDECO, and the mode decoder. This is done from the maintenance switch XSW and the test mode deployment circuit CTLFF. Similarly, the extraction test data signal FDDT from the active side forward highway is extracted using the forward highway digital interface device FIIIE, the forward test highway selection circuit FSELO, and the mode decoder N0 E DEC to the maintenance switch MSw and the test mode deployment circuit. This is done from CTL FF.

Insertion of the insertion test data signal BIDT and extraction of the extraction test data signal BDDT on the backward highway are performed by the backward highway digital interface device 2! B-port IE, backward test signal insertion TDC
Maintenance switch MSw and test mode deployment circuit C using selection circuit BDECI, backward network decoder circuit BDEGO, backward test highway selection circuit BSELO and mode decoder MODEDEC
Performed from Ding L FF.

With this configuration, it is possible to take the four modes described above and perform communication path tests for each mode. However, these circuit elements are not always involved for all of these test modes, typically only some of the forward and backward side elements are involved.
Therefore, compared to the functionality of the device, the device configuration is complex, has many circuit elements, and requires a large amount of laying cables for signal transmission and reception between devices, thus taking up a large amount of space and making it impossible to realize a compact device. Ta.

However, as described above, according to the embodiment of the present invention, the time-division channel test signal is transmitted from the time-division connector device TDC to the channel test device! Extraction to tSP-E is performed by selecting either the forward highway or the backward highway. In addition, the insertion of the test signal from the time division connector device TUG to the time division communication path is performed by the communication path test equipment J (
The test signal received from the 5PTE is tested by selecting either the forward highway or the backward highway.

Therefore, the following effects can be expected. First, the circuits related to the transmission and reception of test data of the time-sharing connector device ↑DC are simplified. At the same time, the number of cables for transmitting and receiving signals is reduced, and therefore less space is required for their installation.

The configurations of the signal transmitting/receiving circuit and the digital interface circuit of the communication path testing device 5PTH are simplified. For these reasons, the entire device is constructed compactly.

(Effects of the Invention) As described above, according to the present invention, the test credibility of the time-division communication path is extracted by selecting either the forward highway or the packward highway, and the test integrity of the time-division communication path is selected. Test 1; was inserted by selecting either forward highway or backward highway force.

Therefore, the circuits related to the test data transmission and reception of the time-sharing connector device are simplified, the cables V for signal transmission and reception are reduced, and therefore the space required for them is also reduced. The configuration of the digital interface circuit and digital interface circuit are also simplified, and the entire device is configured compactly.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the arrangement of FIGS. 1A and 1B, and FIGS. 1A and 18 are diagrams showing a specific implementation in which the test signal transmitting/receiving device for a time division communication path according to the present invention is applied to a division telephone switching system. FIG. 2 is a diagram showing the arrangement of FIGS. 2A and 2B; FIG. 2A and 2B are diagrams showing an example of the configuration of a test signal transmitting/receiving device for a time-division channel according to the prior art. It is a system block diagram. Explanation of codes for the -L11 part CDIE, , , Common highway digital interface device CTL, , Test mode control circuit CTL FF, , Test mote deployment circuit RoEGG, , ,
Network decoder circuit DEC1, , test signal insertion ↑oc 1 selection circuit old 909. Digital interface circuit INF, , , Maintenance equipment interface circuit INS, , , Test signal insertion circuit MODE DEC, Mote decoder MSW, , , Maintenance switch N5EL, , Network selection circuit SELO, ,
, test highway selection circuit 5EL1. , , Tested T
a1c selection circuit 5PTE, , , communication path test device TDC, ..., time division connector device patent applicant Oki Electric Rigyo Co., Ltd. Agent Kutsutori 1 Takao Oinuyama

Claims (1)

[Claims] 1. A communication path testing means for testing a time-division communication path including a plurality of forward highways and backward highways, and a time-division connector means for connecting the communication path testing means to the time-division communication path. In the time-division communication path test signal transmitting/receiving device, the communication path testing means extracts test data and first selection information for selecting a highway into which test data is to be inserted from among the plurality of forward highways and backward highways. sending second selection information for selecting a highway to be used and test data to the time division connector means, the time division connector means receiving first selection information and test data from the communication route testing means; selecting and inserting means for selecting a highway according to the first selection information and inserting the test data therein; receiving second selection information from the communication path testing means and selecting a highway according to the second selection information; 1. A test signal transmitting/receiving device for a time-division communication path, comprising: a selection extraction means for extracting test data from the test data and sending it to the communication path testing means. 2. The device according to claim 1, wherein a plurality of the time-sharing connector means are connected to the communication path testing means, and the communication path testing means has a selection function for selecting the plurality of time-sharing connector means. means, the selection means transmits first selection information to the selection insertion means included in the selected time division connector means, and the selection extraction means included in the selected time division connector means. A test signal transmitting/receiving device characterized in that the test signal transmitting/receiving device transmits second selection information to and receives test data. 3. In the device according to claim 1, the time-division communication path includes a duplex time-division switch network, and the selective insertion means includes a duplex time-division switch network. A test signal transmitting/receiving device characterized in that test data is inserted by selecting either a 0-system forward highway, a 1-system forward highway, or a backward highway. 4. The device according to claim 1, wherein the time division communication path includes a duplex time division switch network, and the selection and extraction means selects the duplex time division switch network. A test signal transmitting/receiving device that extracts test data by selecting one of a forward highway, a 0-series backward highway, or a 1-series backward highway.