JPH0385852A - Channel diagnostic system for subscriber circuit - Google Patents

Abstract

PURPOSE:To improve the diagnostic accuracy of a channel of a subscriber circuit by individually diagnosing a channel in each direction independently between a subscriber terminal equipment of a subscriber circuit and an inside of an exchange. CONSTITUTION:A signal insertion circuit 4 forms a route sending a signal of a signal generating circuit 2 to a subscriber circuit 1 of a diagnostic object. A test signal of a prescribed frequency is sent from the signal generating circuit 2 and a test signal via hybrid circuits 12, 8 is detected by a signal detection circuit 7 to confirm the signal level thereby confirming the normality of the channel in a direction from the inside of the exchange to the subscriber terminal equipment. Then a signal extraction circuit 5 forms a route inputting a test signal from the subscriber circuit 1 of a diagnosis object to the signal detection circuit 3. A signal generating circuit 6 sends a test signal of a prescribed frequency and the test signal via the hybrid circuits 8,12 is detected by the signal detection circuit 3 to confirm the signal level thereby confirming the normality of the channel in a direction from the subscriber terminal equipment to the inside of the exchange. Thus, the diagnostic accuracy is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for diagnosing a communication path of a subscriber circuit connected to a subscriber terminal by two wires.

[Conventional technology]

FIG. 2 is a block diagram showing an example of a conventional subscriber circuit communication path diagnosis method. Conventionally, this type of diagnostic method uses an unbalanced method that switches the switching relay 11 in the subscriber circuit 1 to be diagnosed to give two lines of the communication path to the subscriber terminal a constant return loss for diagnosis. Connect to impedance circuit 9,
A test in which a test signal of a constant frequency from the signal generation circuit 2 is sent to the subscriber circuit 1 by the signal insertion circuit 4, and is reflected from the unbalanced impedance circuit 9 via the hybrid circuit 12 that performs 2-wire and 4-wire signal conversion. The signal is extracted by the signal extraction circuit 5, the test signal is received by the signal detection circuit 3, and the signal level is checked to confirm the normality of the communication path.

[Problems to be solved by the invention]

The conventional subscriber circuit call path diagnosis method described above simultaneously examines the call path from the inside of the exchange (switch) to the subscriber terminal and the call path ε from the subscriber terminal to the inside of the exchange. There is a problem in that the normality of each road cannot be confirmed individually.

An object of the present invention is to enable the normality of each communication path from the inside of the exchange to the subscriber terminal and from the subscriber terminal to the inside of the exchange to be individually confirmed, thereby improving diagnostic accuracy. It is an object of the present invention to provide a method for diagnosing communication paths of user circuits.

[Means to solve the problem]

The subscriber circuit communication path diagnosis method of the present invention uses two-wire signals and four-wire signals.
a hybrid circuit that performs signal conversion between line signals; a first signal generation circuit that is connected to the 4-wire measurement input of the hybrid circuit and generates a first test signal; and a first signal generation circuit that is connected to the 4-wire side output of the hybrid circuit. A first signal detection circuit that detects the second test signal, a switching means that connects the two-wire communication path to the subscriber terminal to the two-wire side of the three-way hybrid circuit before switching, and a connection between the two-wire signal and the four-wire signal. It has a signal conversion means of 4
a subscriber circuit connected to the inside of the exchange via a line communication path, a second signal generation circuit that generates the second test signal, and a second signal detection circuit that detects the first test signal. , a signal insertion circuit provided in the 4-wire communication path for inserting the second test signal from the second signal generation circuit and sending it to the subscriber circuit; a signal extraction circuit extracting the first test signal from the circuit and sending it to the second signal detection circuit; The first test signal from the first signal generation circuit is detected by the second signal detection circuit, and the first test signal from the second signal generation circuit is detected by the second signal detection circuit.
The communication path of the subscriber circuit is diagnosed by detecting the second test signal from the signal generation circuit by the first signal detection circuit.

〔Example〕

Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of the present invention. The communication path diagnosis method of this embodiment is similar to the conventional example shown in FIG.
A switching relay 11 that switches a 2-wire communication path to a subscriber terminal, and a hybrid circuit 1 that converts signals between 2-wire and 4-wire.
2, a plurality of subscriber circuits 1 connected to the inside of the exchange via a four-wire communication path, a signal generation circuit 2 that generates a test signal of a constant frequency, and a signal detection circuit 3 that detects the test signal. , a signal insertion circuit 4 provided in the 4-wire communication path for inserting the test signal from the signal generation circuit 2 and sending it to the subscriber circuit 1; and a signal insertion circuit 4 provided in the 4-wire communication path for extracting the test signal from the subscriber circuit 1. The signal extracting circuit 5 sends the signal to the signal detecting circuit 3. The difference between this embodiment and the conventional example is that the circuit connected at the time of diagnosis by one of the switching relays 11 of the subscriber circuit 1 is not an unbalanced impedance circuit 9, but a test signal of a constant frequency is input to the 4-wire side input. The hybrid circuit 8 is connected to a signal generation circuit 6 that generates a test signal, and a signal detection circuit 7 that detects a test signal is connected to the output on the 4-wire side, and performs signal conversion between a 4-wire signal and a 2-wire signal.

Next, the communication path diagnosis operation will be explained.

First, the switching relay 11 of the subscriber circuit to be diagnosed is operated to connect the two-wire communication path to the hybrid circuit 8 for diagnosis.

The signal insertion circuit 4 creates a route for sending the signal from the signal generation circuit 2 to the subscriber circuit 1 to be diagnosed. A test signal of a constant frequency is sent from the signal generation circuit 2, and the test signal that has passed through the hybrid circuits 12 and 8 is sent to the signal detection circuit 7.
By detecting and checking the signal level, the normality of the communication path from the inside of the exchange (switch) to the subscriber terminal is confirmed.

Next, the signal extraction circuit 5 detects the subscriber circuit 1 to be diagnosed.
A route is created to input the test signal from the signal detection circuit 3 to the signal detection circuit 3. A test signal of a constant frequency is sent from the signal generation circuit 6, and the signal detection circuit 3 detects the test signal that has passed through the hybrid circuit 8.12 to check the signal level, thereby determining the direction from the subscriber terminal to the inside of the exchange. Check the normality of the call path.

When the diagnosis of the subscriber circuit 1 is completed, the switching relay 11 is released and the signal insertion circuit 4. Each test route created by the signal extraction circuit 5 is restored.

As described above, the communication paths of all subscriber circuits 1 are diagnosed for each subscriber.

〔Effect of the invention〕

As explained above, the subscriber circuit call path diagnosis method of the present invention includes a hybrid circuit connected to two wires of the subscriber circuit to the subscriber terminal, a test signal generation circuit, and a detection circuit. Since the communication path in each direction between the subscriber terminal and the inside of the exchange can be individually and independently diagnosed, the diagnostic accuracy of the communication path of the subscriber circuit can be improved.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a block diagram showing an example of a conventional subscriber circuit call path diagnosis method.

Claims (1)

[Claims] a hybrid circuit that performs signal conversion between a 2-wire signal and a 4-wire signal; a first signal generation circuit that is connected to a 4-wire side input of the hybrid circuit and generates a first test signal; and a 4-wire circuit of the hybrid circuit; a first signal detection circuit that is connected to the side output and detects a second test signal; a switching means that switches the two-wire communication path to the subscriber terminal and connects it to the two-wire side of the hybrid circuit; a subscriber circuit having signal conversion means between line signals and connected to the inside of the exchange via a four-wire communication path; a second signal generating circuit generating the second test signal; and a second signal generating circuit for generating the second test signal; a second signal detection circuit that detects a signal; a signal insertion circuit that is provided in the four-wire communication path and inserts the second test signal from the second signal generation circuit and sends it to the subscriber circuit; a signal extraction circuit provided in the four-wire communication path for extracting the first test signal from the subscriber circuit and sending it to the second signal detection circuit, the two-wire communication path to the subscriber terminal; is switched and connected to the hybrid circuit, the first test signal from the first signal generation circuit is detected by the second signal detection circuit, and the second test signal from the second signal generation circuit is detected. A communication path diagnosis method for a subscriber circuit, characterized in that the communication path of the subscriber circuit is diagnosed by detecting the signal by the first signal detection circuit.