JPH071870Y2 - Optical repeater alarm instruction signal transmission circuit - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The present invention relates to an alarm instruction signal (hereinafter referred to as an AIS signal) transmission circuit of an optical repeater, and has been made so as not to lose the AIS signal transmission function particularly during maintenance. The present invention relates to an AIS signal transmission circuit of an optical repeater.

(Prior Art) Generally, an optical repeater has a structure as shown in FIG.

In FIG. 2, the optical receiver board 1 and the optical transmitter board 2 of the optical transmitter / receiver 10 on the upper side of the drawing receive from the adjacent W station via the transmission path and send to other adjacent E station via the transmission path. The optical receiver board 1 and the optical transmitter board 2 of the optical transmitter / receiver 20 on the lower side of the figure.
Is similarly received from the E station and transmitted to the W station. Since these two systems differ only in the transmission direction, only one will be described.

In FIG. 2, the optical input signal 4 from the transmission line on the W station side is shown.
Enters the optical receiver board 1, is converted into an electric signal, is equalized and amplified and is discriminated, and the data signal 5 and the clock signal 6 are sent to the optical transmitter board 2. In the optical transmission board 2, it is converted into an optical signal again and the output 8 is sent to the transmission line. It should be noted that all kinds of signal processing in the optical repeater are performed in the state of electric signals. Further, 24 is an optical input signal from the E station, 25 is a data signal, 26 is a clock signal, 7 and 27 are clock signals for AIS signals, and 28 is an optical output signal to the W station.

FIG. 3 is commonly performed. 1 shows a detailed configuration of an AIS transmission circuit of an optical transmission / reception unit 10 of a system that monitors a relay station from terminal stations on both sides using the same line as a main signal.

Even if the optical input signal 4 is disconnected in FIG. 3, it is desirable that the optical signal output 8 is sent out. Therefore, the optical input disconnection alarm signal 14 and the error alarm signal 15 of the optical receiver board 1 have low potential levels. Is detected and the data signal 5 and the AIS signal 16 are switched. The clock signal 7 for the AIS signal is supplied from the oscillator 3 inside the repeater, and the fixed pattern "1010" of the logic signal is sent as the AIS signal. In this way, even if the line between the W station and the repeater is disconnected, the repeater can be monitored from the E station side. Incidentally, 33 is a D-type flip for making an AIS signal, and 34 is an AND circuit.

(Problems to be Solved by the Invention) In the conventional optical repeater described above, if the optical receiving board 1 is removed for maintenance and inspection, the input signal 4 from the W station side in FIG. 3 cannot be received. Since no alarm signal is sent to the optical transmission board 2, switching by the switching control signal 17 in the switching unit 11 is not performed. Therefore, AIS
The signal 16 is not transmitted, and monitoring from the E station side becomes impossible.

As described above, when the optical receiving board 1 is pulled out for the purpose of maintenance / inspection or replacement of the unit at the relay station, there is a problem that neither the W station nor the E station can monitor.

An object of the present invention is to solve the above problems and to provide an AIS signal transmission circuit of an optical repeater in which an AIS signal is transmitted even when the optical receiver is removed for maintenance and inspection. .

(Means for Solving Problems) The optical receiver converts the received optical signal into an electric signal and sends out the data signal, and the inputted electric signal into the optical signal and sends out the signal. In an optical repeater composed of an optical transmitter having an electric / optical converter, the optical receiver transmits a ground signal when the optical transmitter / receiver is in a connected state and connects with the optical transmitter / receiver. Is in a released state, release identification means for sending a disconnection signal having a potential different from the ground signal, and an error signal having substantially the same potential as the ground signal only when a failure occurs, At least one error signal generating means for sending out an error signal having substantially the same potential as the disconnection signal except at the time of a failure is provided, and the optical receiving unit sets the potential of the signal from the disconnection identifying means to the ground signal. Invert between the disconnect signals An inverter for sending an inverted signal, and a switching control signal connected to the inverter and the error signal generating means, ANDing the inverted signal and the error signal, and at least one of which has the same potential as the ground signal. Connected to the optical receiving board and the alarm instructing means, and switching the data signal to the alarm instructing signal by the switching control signal, And a switching unit for sending the light to the light conversion unit.

(Example) Next, the Example of this invention is described.

FIG. 1 is a circuit configuration diagram showing an embodiment according to the present invention.

In FIG. 1, the optical receiver board 1 has an optical input signal 4 from the transmission line.
To send the data signal 5 and the clock signal 6 to the switching section, and when the optical input is cut off, the alarm signal 14 indicating the detection and the error alarm signal 15 indicating the error are output. Further, it outputs a ground signal 13 inside the optical receiver 1 which is a feature of the present invention. Here, the optical receiving board 1 is provided with a light receiving element, converts the optical input signal 4 transmitted by the optical cable line into an electrical signal, and sends it as a data signal 5 to the switching unit 11. At this time, the optical receiver 1
Detects the intensity of the optical input signal 4 and outputs an alarm signal 14 if the intensity is below a certain value due to deterioration of the optical semiconductor laser of an adjacent optical repeater over time, disconnection of the optical cable line, or the like. The alarm signal 14 is a signal due to a potential change that maintains a high potential when the optical input signal 4 is above a certain value and changes to a low potential when below a certain value. Further, the optical receiving board 1 detects an error in the optical input signal 4, and when an error of a certain value or more is detected, the same error alarm signal 15 is transmitted. The optical receiver board 1 is grounded when it is inserted in the optical repeater and sends out the ground potential signal 13 having a low potential. When the optical receiver board 1 is extracted and disconnected from the optical repeater, the optical receiver board 1 is disconnected from the ground. Therefore, it is provided with a circuit that sends a ground signal so that the potential becomes high. The ground signal 13 is input to the AND circuit 30 together with the alarm signal 14 and the error alarm signal 15 via the inverter 31, and the output of the AND circuit 30 serves as the switching control signal 17 to control the switching of the switching unit 11. On the other hand, the AIS clock signal output from the oscillator is input to the D-type flip-flop 33 to become the AIS signal 16 and the AIS clock signal 7
It is also input to the switching unit 11. The switching unit 11 switches the data signal and the AIS signal 17 together with the respective clock signals by the switching control signal 17, and the switched data signal 18
And a clock signal 19 are output and input to the electrical / optical conversion unit 12. The electric / optical converter 12 converts the input electric signal into an optical signal and outputs it as an optical output signal 8 to the transmission line.

With such a configuration, when the optical receiver board 1 is inserted, the ground signal 13 becomes a power failure level. There is. Therefore, the output (switching control signal) 17 of the AND circuit 32 is switched to an abnormal state by sending the switching control signal 17 of a low potential only when either the alarm signal 14 of the other input or the error alarm signal 15 has a low potential, and the switching is performed. 11 outputs 18 AI
It switches to the S signal, and otherwise operates normally to send the data signal.

Next, when the optical receiver 1 is pulled out, the line of the ground signal 13 is released, so the output of the inverter 31 becomes a low potential,
The output of the AND circuit 32 always has a low potential even if the other inputs have a high potential.

Therefore, the switching unit 11 receives the low potential of the control signal 17 and receives the AIS signal 1
Switch to 6 side and send AIS signal to transmission line.

Therefore, when the optical input is cut off, when an error occurs,
Even when the optical receiver is removed, the AIS signal is sent to the E station side, and the E station can monitor the repeater.

(Effects of the Invention) As described above, the present invention includes the ground signal inside the optical receiving board in the switching control signal, so that when the optical receiving board needs to be pulled out for maintenance or other purposes, the terminal station is in operation. This has a great effect on maintenance that the optical unit can be replaced with peace of mind while being monitored by.

[Brief description of drawings]

FIG. 1 is a circuit configuration diagram showing an embodiment according to the present invention. FIG. 2 is a system block diagram of a general optical repeater. FIG. 3 is a circuit configuration diagram showing an example of an AIS signal transmission circuit of a conventional optical repeater. 1 …… Optical receiver 2 …… Optical transmitter 3 …… Oscillator 4,24 …… Optical input signal 5,25 …… Data signal 6,26 …… Clock signal 7,27 …… AIS clock signal 8,28 ...... Optical output signal 9 ...... Optical repeater 10,20 ...... Optical transmitter / receiver 11 ...... Switching unit 12 ...... Electric / optical converter 13 ...... Geologic signal 14 ...... Alarm signal 15 ...... Error alarm signal 16 …… AIS signal 17 …… Switching control signal 18 …… Switching part data output 19 …… Switching part clock output 31 …… Inverter 32,34 …… AND circuit 33 …… D type flip-flop

Claims (1)

[Scope of utility model registration request] 1. An optical transmitter / receiver unit for converting a received optical signal into an electric signal and transmitting a data signal, and an electric / optical conversion unit for converting an inputted electric signal into an optical signal and transmitting the same. In the optical repeater configured by an optical transmitter having the optical transmitter, the optical receiver transmits a geological signal when the optical transmitter is connected to the optical transmitter, and the optical transmitter is disconnected from the optical transmitter. The disconnection identifying means for sending a disconnection signal having a potential different from that of the ground signal, and an error signal having a potential substantially the same as that of the ground signal only when a failure occurs. At least one error signal generating means for sending out an error signal having substantially the same potential as the disconnection signal, wherein the light receiving section is configured to set the potential of the signal from the disconnection identifying means between the ground signal and the disconnection signal. Invert with and send the inverted signal An inverter that is connected to said error signal generating means and the inverter,
An AND circuit that takes a logical product of the inversion signal and the error signal and sends a switching control signal when at least one of them is at the same potential as the ground signal; an alarm instructing means that sends out an alarm instructing signal; An optical repeater, comprising: a receiving board and a switching unit that is connected to the alarm instructing means and that switches the data signal to the alarm instructing signal by the switching control signal and sends the alarm signal to the electric / optical conversion unit. Alarm instruction signal sending circuit.