KR100748307B1 - The Selective Testing Device of E-1 Link in Access Gateway System - Google Patents

Abstract

The present invention relates to an E-1 digital repeater selection test apparatus for an access gateway system. The present invention relates to a test tone generating apparatus for generating a test tone in a low frequency voice band, and an E-1 matching for inserting a power loss between the two circuits to be the least. An access gateway and a digital switch each having a circuit; An E-1 digital transmission path connecting the access gateway and the digital exchange; And a plurality of repeaters incorporating a voice band filter for passing only a specific frequency in the E-1 digital transmission path, and various kinds of test tones spaced at regular intervals within the voice frequency band and the repeaters of the repeater. The loopback function can be used to identify faulty relays and to test fault and fault conditions separately. Thus, in the present invention, when a failure or failure of an E-1 digital transmission path accommodating an access gateway system to a digital exchange occurs, it is possible to repair the failure quickly by checking in which relay a failure occurs in detail. It is effective in shortening the cost and reducing the effort and cost of repairing a failed repeater.

Description

E-1 digital repeater selective test device for access gateway system {The Selective Testing Device of E-1 Link in Access Gateway System}

1 is a block diagram of a digital transmission path between a conventional access gateway and a digital switch.

Figure 2 is a view for explaining the principle of the repeater test method according to the present invention.

The present invention relates to an E-1 digital repeater selection test apparatus of an access gateway system, and more particularly, is installed on an E-1 (2.048 Mbps) digital transmission line connecting an access gateway system to a digital exchange. It is an E-1 digital repeater selection test device of an access gateway system for a device capable of selecting a specific repeater among a plurality of repeaters and individually testing the failure and failure states of the repeater.

Conventionally, a test method for checking a fault occurring in an E-1 digital transmission path only in the end-to-end section has become mainstream.

While monitoring the performance or operational status of the digital transmission line, if a fault condition is detected, the service will be discontinued and entered into the testing and troubleshooting phase.

For example, in T-1 (1.544 Mbps) systems in North America, the Framing Signal is amplified in normal conditions to maintain a specific relay in operation, and when the system goes into an abnormal state, the Framing Signal is lost and the relay recovers. Alarm is issued and the system is disconnected from service and enters the procedure to confirm the failure.

Hereinafter, the related art will be described with reference to the accompanying drawings.

Currently in Korea, the access gateway system and the digital exchange are configured as shown in FIG.

An E-1 digital transmission path is provided between the access gateway 1 and the digital switchboard 3, and repeaters 2a and 2b are provided on the E-1 digital transmission path at 1.8 km intervals.

In the case of a conventional repeater failure, among the repeaters 2a and 2b installed on the E-1 digital transmission path where the failure occurs, each relay line is directly approached by an operating personnel to check the repeater that has failed. Try it.

Therefore, the conventional repeater troubleshooting procedure is a time-consuming and laborious task.

An object of the present invention is to select a specific repeater from the plurality of repeaters installed on the E-1 digital transmission line connecting the access gateway system to the digital exchange, so that the failure and failure status of the repeater can be individually tested, and the digital In the event of a failure or failure of the transmission path, it is specifically to check which repeater has failed so that the failure can be repaired quickly.

The present invention provides an access gateway and a digital switch, each having a test tone generating device for generating a test tone in a low frequency voice band, and an E-1 matching circuit inserted to minimize power loss between the two circuits; An E-1 digital transmission path connecting the access gateway and the digital exchange; And a plurality of repeaters incorporating an audio filter for passing only a specific frequency in the E-1 digital transmission path, and various kinds of test tones spaced at regular intervals within the audio frequency band. By using the loopback function of the repeater and the repeater, it is possible to identify the repeater that has failed and to test the failure and the failure status separately.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 2 is for explaining the principle of the repeater test method according to the present invention, the test tone generating device (12, 32) for generating a test tone of the low frequency voice band and E inserted to transmit the least loss of power between the two circuits An E-1 digital transmission line and a voice band filter connecting the access gateway 10 and the digital exchanger 30 including the -1 matching circuits 11 and 31, respectively, and the access gateway 10 and the digital exchanger 30; It is provided with a plurality of repeaters 20a to 20c incorporating 21 to 23 and having a loopback function.                     

When a failure or failure occurs in the E-1 digital transmission path, a test tone is generated to separate the transmission path from the service state and generate a special test tone to specifically identify the location of the failure on the access gateway 10 system side. A test tone generator 12 is connected.

Then, the test tone generating device 12 may generate while varying the test tones of various kinds of low frequency voice bands.

Each repeater 20a to 20c has a built-in low-frequency voice band filter that responds only to a test tone of a specific frequency among the test tones, and if a test tone of a different frequency is generated and transmitted while changing a test pattern, a failure or failure may occur. The generated repeater does not already perform its function, so the test tone cannot be transmitted or the voice band filter built in the repeater does not work properly so that the test tone of the frequency does not return or the signal is below the reference value. Will return, so you can check the location of the repeater that has failed.

For example, to test the second repeater 20b in the drawing, first, the transmission path connected to the digital exchanger 30 side of the second repeater 20b is shorted by a separate remote control device.

Then, the test tone generator 12 of the access gateway 10 generates a test tone having a frequency magnitude of the voice band filter 22 embedded in the second repeater 20b.

At this time, when the test tone is received by the first repeater 20a, the first repeater 20a sends the test tone to the second repeater 20b, and parallelly outputs the test tone to the voice band filter 21. ) Is detected.

However, since the frequency of the test tone is different from that of the voice band filter 21, it is not detected. Therefore, the first repeater 20a does not loop back and only the test tone is transmitted to the second repeater 20b.

Then, the second repeater 20b receiving the test tone detects the test tone in the voice band filter 22.

In this case, since the frequency of the test tone is the same as the frequency of the voice band filter 22, the second repeater 20b loops back and the test tone passes through the first repeater 20a of the access gateway 10. The test tone generator 12 is returned.

As described above, when the test tone is normally returned, there is no abnormality up to the first repeater 20a between the second repeater 20b and the E-1 digital transmission path and the access gateway 10 and the second repeater 20b. It seems to be.

If the test tone does not return, test the first repeater 20a in the same manner as above, and when the test tone returns, E-1 digital transmission between the first repeater 20a and the second repeater 20b. If it is determined that a failure or failure occurs in the second relay 20b or the test tone does not return, the E-1 digital transmission path between the access gateway 10 and the first repeater 20a or the first repeater 20a is not present. It seems that a failure or failure has occurred.

The operator can then go directly to the field where the problem occurred and resolve the problem.

Of course, this function can also be implemented by the digital exchange 30 side.

The voice band filters 21 to 23 built in the repeaters 20a to 20c are set to different frequencies, and each voice band filter may vary in frequency as necessary.

In addition, the test tone is not transmitted through the voice band filter to the repeater in the next order, but the test tone is processed in parallel, so that the test tone is detected while the test tone is transmitted to the repeater in the next order, thereby detecting the voice band between the repeaters. The frequency bands of the filters only need to be different.

In the present invention, when a failure or failure of an E-1 digital transmission path accommodating an access gateway system to a digital exchange occurs, it is possible to repair the failure quickly by checking which repeater has occurred in detail. It shortens and reduces the effort and cost for repairing a failed repeater.

In addition, it is effective to provide a high profit service by maintaining a high transmission quality.

Claims (4)

An access gateway and a digital switch, each having a test tone generating device for generating a test tone in a low frequency voice band, and an E-1 matching circuit inserted to minimize power loss between the two circuits; An E-1 digital transmission path connecting the access gateway and the digital exchange; And The E-1 digital repeater selection test apparatus of the access gateway system, characterized in that the E-1 digital transmission path is provided with a plurality of repeaters having a loopback function and a voice band filter for passing only a specific frequency. The method of claim 1, The test tone is not transmitted through the voice band filter to the repeater in the next order, but the repeater processes the test tone in parallel, and detects the test tone by transmitting the test tone to the repeater in the next order. E-1 digital repeater selection test device for access gateway system. The method of claim 2, When a test tone is detected in the voice band filter, And the repeater loops back and the test tone is transmitted to a previous repeater. The method of claim 1, The voice band filter of the repeater, E-1 digital repeater selection test apparatus of an access gateway system, characterized in that the voice band filter of the other repeater is set to a different frequency, each voice band filter can vary the frequency as necessary.

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