JPS619064A - Test system for time division exchange system - Google Patents

Abstract

PURPOSE:To reduce the line test time and to relieve the load of a maintenance personnel by using a command from plural time division line concentrators without intervention of a central controller to reflex automatically a communication line between the said concentrators and an exchange thereby attaining the test of plural communication lines at the same time from the plural line concentrators. CONSTITUTION:In testing a communication line ln between a line circuit LUn and an ELUn, an LU number LUn and test command are given to a test circuit TST from an operation display section CNS, then a transmission signal from a switch SW on a backward superhighway BSHW is suppressed by a command signal on a signal line TST1, and a test signal is transmitted succeedingly to a line reflection command signal from a test signal line TBD. The signal reaches the circuit ELUn via DMPX- LUn-ln-HW. When the circuit ELUn detects a reflected command signal by a reflection signal detecting circuit RTNDET, reflects the signal for a prescribed time to the selection circuit SEL and transmits to the reflected command signal to the transmission line HW. The reflected command signal is received by the circuit TST, the reception signal and the transmitted test signal are collated and the result of collation is displayed on an operation display section CNS.

Description

Detailed Description of the Invention (Technical Field) The present invention relates to a test method in a time division switching system. Conventionally, in a time division switching system configured as shown in FIG. When testing a communication line connecting a division concentrator and a time-division switch, the central control unit instructs the time-division concentrator to turn back the test communication line via the time division switch, time division multiplex transmission line, and control line. The central control unit sends test data to the test communication line via the time division switch, and the data returned within the time division concentrator via the time division multiplex transmission line and the communication line is sent to the central control unit. We use a method of matching.

In the conventional method described above, a central controller sequentially performs a communication line connection test with multiple time-division concentrators via a time-division switch, which requires a large amount of test time. Since a switching system must be involved, there is a drawback that the burden on the maintenance personnel within the time-sharing switch increases.

(Objective of the Invention) The present invention solves these problems and automatically connects communication lines connecting time-division concentrators and time-division exchanges based on instructions from multiple time-division concentrators without the intervention of a central controller. This reduces line testing time by making it possible to test multiple communication lines simultaneously from multiple time-sharing concentrators without the intervention of a central control device, and also allows maintenance personnel to test the time-sharing exchanges without the intervention of maintenance personnel. The purpose is to reduce the burden on people.

The features of the present invention for achieving this object include a time division switch, a time division concentrator controlled by the time division switch,
In a time division switching system having a plurality of communication lines connecting a time division exchange and a time division concentrator via time division multiplex transmission lines, when a line return instruction signal is detected in the time division exchange, the communication line The time division concentrator transmits the line return instruction signal to the communication line to be tested on the time slot corresponding to the communication line, and then transmits the test signal '
This is a time-division switching system test method in which a communication line is tested by transmitting a test signal and comparing the test signal with a received signal.

Hereinafter, the present invention will be explained in detail based on one embodiment with reference to the drawings.

(Structure and operation of the invention) FIGS. 2 and 3 are block diagrams of an embodiment of the invention. FIG. 2 is a block diagram for testing a communication line connecting a time division concentrator and a time division switch. A multiplexing circuit MPX, F! multiplexes the signal received at the LU to a predetermined time position (hereinafter referred to as a time slot) on the forward superhighway FSHW. A time division switch which exchanges the signals on the time slots on the 3Hlli and the signals on the backward superhighway BSHW time slots.
suw Distribution circuit DMPX for distributing the above signal to the line circuit LU corresponding to the time slot, test circuit TS? , and an operation display unit CNS that issues test instructions to the TST and displays test results from the TST.
It is composed of f. The time division exchange EX also includes a communication path device TSW and a TSII which mutually exchange signals on the time slots of the line circuit ELUon%ELU for connecting the time division multiplex transmission path Hw.
It is composed of a control device CTL that performs + control.

FIG. 3 shows a configuration example of the ELU shown in FIG. 2, which includes a receiving circuit RV that receives signals from the time division multiplex transmission line Hw, a transmitting circuit ΩV that sends signals to the time division multiplex transmission line H1ll, and a receiving circuit RV. A serial-to-parallel converter circuit SP that converts the received serial signal into a constant parallel signal, and a return signal detection circuit RTN that detects a return instruction signal from the received signal converted by the sp.
DE? and RT) the communication path device TS according to the instructions of IDET.
It is composed of a selection circuit SEL that selects the signal from Ilf or the reception circuit RV.

In Figure 2, when testing the communication line n that connects the LUn of the line circuit LC and the ELUn of the time-sharing exchange @EX, send the LU number LUn and communication line test instruction to the test circuit TST from the operation display unit CNS. Then, the test circuit TST detects the LU on the backward superhighway BSHW by the test instruction signal on the test instruction signal line TSTI.
time division switch SIl on the time slot corresponding to n
LUn from the test signal line TBD by suppressing the transmission signal from
EL of time division exchange EX on the time slot corresponding to
Following the line return instruction signal to Un, a test signal is sent. The signal for ELIJn from the test circuit TST is DNPX -LUn -in -HW -ELUn
The line circuit ELUn is reached via the route .

In FIG. 3, the line circuit ELUn constantly monitors the received signal converted into parallel by the serial/parallel conversion circuit SP by the loopback signal detection circuit RTNDET, and when it detects a line loopback instruction signal, it sends the signal to the selection circuit SEL for a certain period of time. turn back,
The 0 selection circuit SEL, which sends a return instruction signal onto the instruction signal line RTNI, responds to this return instruction signal, suppresses the signal sent from the time division switch, and transmits the signal received by the receiver circuit RV via the transmitter circuit DV. It is sent out between division multiplex transmission lines.

The test circuit TST Karano test signal returned by EL- as described above is shown in FIG.
The test circuit TST receives via LUn-MPX on the time slot corresponding to LUn of the forward superhighway FSH- of the time division concentrator LC.

The test circuit TST compares the received signal and the transmitted test signal, and displays the verification result on the operation display unit CNS. Based on this display result, the tester can check the communication line between the time division concentrator LC and the time division exchange EX. You can determine whether or not it is connected properly.

(Effects of the Invention) As explained above, according to the present invention, lines connecting time-division concentrators and time-division exchanges are automatically looped back based on instructions from a plurality of time-division concentrators without the intervention of a central controller. , it is possible to test multiple lines at the same time from multiple time-sharing concentrators without the intervention of a central control device, thereby reducing the line test time, and eliminating the need for the intervention of maintenance personnel on the time-sharing exchange side, reducing the burden on maintenance personnel. It is possible to provide a time-sharing exchange system testing device that can reduce the amount of damage.

Furthermore, the present invention has the advantage that it can be applied to various systems because it can economically perform tests between devices connected via a transmission path.

[Brief explanation of drawings]

FIG. 1 is a configuration example of a time division switching system, FIG. 2 is a block diagram for testing a communication line connecting a time division concentrator and a time division exchange according to the present invention, and FIG. 3 is shown in FIG. It is a configuration example of a line circuit ELU according to the present invention. LC-m temporary division concentrator, MPX-m multiplexing circuit, S-m temporary division switch, FS) IW-11 forward superhighway, BS
HW---Backward Super Highway, DMPX
-m-distribution circuit. LUo, -n---Line circuit 0"'n. TST-m-Test circuit, CN5-m-Operation display, T
BD-m-test signal line, TSTI-m-test instruction signal line,
P1o-1n---communication lines o~n, HW---temporary division multiplex transmission line, EX-m temporary division exchange, CTL---control circuit, EL
Uo-n---line circuit o~n. TSW-m temporary split channel device, RV-m-receiving circuit, nv-m-transmitting circuit, sp
-m-Serial to parallel conversion circuit, RTNDET-m-return signal detection circuit, 5EL-m-
Selection circuit, RTNI-m-return instruction signal line.

Claims (1)

[Claims] In a time division switching system having a time division switch, a time division concentrator controlled by the time division switch, and a plurality of communication lines connecting the time division switch and the time division concentrator via time division multiplex transmission lines, A means for looping back the communication line for a predetermined period of time when a line loopback instruction signal is detected in the time division switch is provided, and the time division concentrator sends the communication line to be tested on the time slot corresponding to the communication line. A time-division switching system testing method characterized in that a communication line is tested by transmitting a line return instruction signal, subsequently transmitting a test signal, and comparing the test signal with a signal received in return.