JPH04337936A - Transmission/reception system - Google Patents

Abstract

PURPOSE:To previously predict a line fault while maintaining an online state by detecting error transmitting a pattern for error detection during idle time when no data are transmitted. CONSTITUTION:When a transmitted signal 12 is turned off, on the side of one modulator/demodulator, the signal of a specified pattern is outputted in place of transmitted data from a pattern generating circuit 4, modulated at a modulation part 5 and outputted to a transmission line connecting terminal 6. On the side of the other modulator, the modulated signal received from a reception line connecting terminal 7 is inputted to a demodulation part 8, and demodulated received data 14 are monitored at an error detection circuit 9. When error is detected, it is counted by an error rate measuring circuit 11 and when exceeding a prescribed error rate, an alarm signal is outputted to an alarm output terminal 9 so as to issue an alarm. Namely, it can be recognized during time excepting for data communication that the data communication has the danger of a fault.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitting/receiving system, and more particularly to testing a system including a line.

0002

[Prior Art] Conventionally, in a transmitting/receiving system including a modulation/demodulation device using a pseudo carrier control function, a carrier is sent out even when a clear to send (CS) signal is off after data communication is completed, and synchronization is always established with the other station. It was only available online, and it was simply idle time. By the way, in conventional transmission/reception systems, when checking the line quality or testing the modem, the online mode was interrupted and the modem and line were tested using the built-in test function of the modem or a modem tester. .

[0003] However, in the above-mentioned conventional transmission/reception system using the pseudo carrier control function, line failures cannot be predicted in advance, so when a failure occurs, online is interrupted and the failure location is found, so it takes a long time to restore online. The drawback was that it took a lot of time.

0004

OBJECTS OF THE INVENTION The present invention has been made to solve the above-mentioned conventional drawbacks, and its purpose is to provide a transmitting/receiving system that can predict line failures in advance while maintaining an online state.

[0005]

[Structure of the Invention] A transmission/reception system according to the present invention includes a transmitter that transmits an error detection pattern during idle time other than data transmission in an online state, and a receiver that is provided with an error detection pattern that transmits an error detection pattern from the transmitter. The present invention is characterized in that it includes an error detection section that detects errors, and a warning notification section that issues a warning when the detected error rate exceeds a predetermined value.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be explained with reference to the drawings.

FIG. 2 is a block diagram showing the configuration of an embodiment of a transmitting/receiving system according to the present invention. In the figure, 4
The modem 1 and the modem 2 are connected point-to-point by a dedicated line 3. Note that 100 and 200 are terminal devices of each modem.

FIG. 1 is a block diagram showing the internal configuration of one of the modulators and demodulators in FIG. 2. As shown in FIG. In the figure, the modulation/demodulation device includes a transmitting section 50 including a pattern generating circuit 4 and a modulating section 5, a receiving section 80 including a demodulating section 8, a clamp circuit 10, and an error detecting circuit 9, and an error rate measuring circuit 11. ing. It is assumed that the other modulation/demodulation device has a similar configuration.

The pattern generation circuit 4 performs data transmission (SD
:Send Data) This circuit receives the transmission data from the input terminal 16 and the transmission signal 12 from the modulation section 5, and outputs the transmission data 18 to the modulation section 5. The modulator 5 modulates the transmission data 18 and outputs a carrier to the transmission line connection terminal 6.

The demodulator 8 inputs the carrier from the reception line connection terminal 7, performs demodulation, and performs carrier detection (CD: Ca
The error detection circuit 10 outputs the error detection signal 13 and the received data 14 to the clamp circuit 10 and the error detection circuit 9. The clamp circuit 10 receives the carrier detection signal 1
3 and received data 14 as input, data reception (RD:R
This is a circuit that outputs received data to the received data output terminal 15.

The error detection circuit 9 receives the carrier detection signal 13
This is a circuit that receives the data 14 and the received data 14 as input, and outputs the error detection result to the error rate measuring circuit 11. The error rate measurement circuit 11 is a circuit that outputs an alarm based on the measurement result to the alarm output terminal 19 based on the output signal from the error detection circuit 9.

Next, the operation of the system of this embodiment having the configuration shown in FIGS. 1 and 2 will be explained.

First, in FIG. 2, both the modulation and demodulation device 1 and the modulation and demodulation device 2 always output a carrier to the transmission line connection terminal 6 even if the signal at the transmission signal output terminal 17 to the terminal device is on or off.

Next, in FIG. 1, on the modulation/demodulation device 1 side, when the transmission signal 12 is turned off, a specific pattern signal is output from the pattern generation circuit 4 in place of the original transmission data. The pattern is modulated by the modulator 5 and output to the transmission line connection terminal 6. Note that when the transmission signal 12 is on, the original transmission data from the data transmission input terminal 16 is modulated and sent from the transmission line connection terminal 6 to the line.

On the modulator/demodulator 2 side, a binary 1 modulated wave signal received from the reception line connection terminal 7 is input to a demodulator 8 . The received data 14 demodulated by the demodulator 8 is monitored by an error detection circuit 9. If an error is detected as a result of monitoring,
The error detection circuit 9 outputs this information to the error rate measurement circuit 11.

The error rate measuring circuit 11 counts the number of errors. When the error rate exceeds a certain predetermined error rate, an alarm signal is sent to the alarm output terminal 19 to warn that there is a risk of failure in data communication. Further, when the carrier detection signal 13 from the demodulator 8 is off, the clamp circuit 10 clamps the received data 14 to binary 1 and outputs it to the data reception output terminal 15.

[0017] By implementing the above control method, the entire system including the line can be tested during free time when data communication is not being performed in the online state, without requiring any manpower, and without interrupting the online operation. .

Various patterns can be considered as the pattern sent out from the pattern generation circuit 4, and for example, a pattern that repeats "ABCD" converted into binary data may be used. Furthermore, the error rate measuring circuit 11 may be configured to issue an alarm signal when three or more errors are detected in, for example, 3×10 6 bits. The configuration may be such that the threshold value can be set externally.

[0019] Furthermore, when an alarm signal is generated,
The following measures can be considered.

[0020] - By outputting an alarm signal, the LED is turned on to inform the outside. This allows maintenance personnel to recognize it.

(2) The output of the alarm signal activates an automatic fallback sequence and performs data speed fallback. As a result, even if the data transmission speed decreases, the error rate decreases and failures can be prevented.

■By outputting the alarm signal, the dial backup sequence is started and the backup line (
(protection line). This allows you to stay online.

[0023]

[Effects of the Invention] As explained above, the present invention allows testing of the entire system, including the line, without interrupting online operations, during free time when data is not being sent in response to the end of data communication. This has the effect that it is possible to know that there is a risk of failure in data communication at a time when data communication is not in progress, and to be able to predict failures in advance.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the internal configuration of a modulation/demodulation device of a transmitting/receiving system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the overall configuration of a transmitting/receiving system according to an embodiment of the present invention.

[Explanation of symbols]

4 Pattern generation circuit 5 Modulation section 8 Demodulation section 9 Error detection circuit 10 Clamp circuit 11 Error rate measurement circuit

Claims (1)

[Claims] 1. A transmitter that transmits an error detection pattern during free time other than data transmission in an online state, and an error detector that is provided in a receiver and detects errors using the error detection pattern from the transmitter. and a warning notifying unit that notifies a warning when the detected error rate exceeds a predetermined value.