JPS5814634A - Monitoring system of optical relay transmission line - Google Patents

Abstract

PURPOSE:To simplify the constitution of a circuit and at the same time to reduce power consumption, by using a surface acoustic wave element for discrimination of a reproduction repeater. CONSTITUTION:A circuit is provided to each reproduction repeater and discriminates a monitoring discriminating signal to be transmitted in a time division way along with a main signal given from a transmitting terminal are addressed to the own device. The surface electrodes more than bit numbers are set to the above-mentioned circuit, and a surface acoustic wave element 11 containing a winding formed on the surface electrode is set in accordance with the discriminating signal of each device. The selection of the own device is discriminated by the output signal of the element 11. In such a way, the constitution of a circuit is greatly simplified with extreme reduction of power consumption com- pared with the case when a memory element is used with an ordinary digital logical circuit for discrimination of selection of the own device.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a monitoring system for transmitting digital optical signals to an optical repeater transmission line in which optical fiber cables and regenerative repeaters are alternately connected. In particular, the present invention relates to a method of individually selecting each regenerative repeater according to its function and monitoring its status during operation of a transmission line.

As optical relay transmission lines are put into practical use as high-speed multiplex communication lines, monitoring methods to maintain high quality transmission lines have become an important issue. Many monitoring methods for this purpose have been proposed in the past. Typical examples include JP-A-55-152434, No. 1983 National Institute of Electronics and Communication Engineers General Conference No.

Wear it with 2234 etc.

According to these techniques, it is possible to remotely monitor the status of a regenerative repeater placed on a transmission path from either the transmitting end or the receiving end, but this is only done when the monitor is not in use.

That is, in order to monitor the transmission path, it is necessary to switch the communication signal flowing through the transmission path to another line, and then transmit a special monitoring signal from the transmitting end. Therefore, the time that can be monitored is limited, and some regenerative repeaters gradually deteriorate, making it difficult to detect them before they become a failure. However, a ninth communication channel and switching device must be installed.

On the other hand, a known method for monitoring optical relay transmission lines while in operation is to use a steel wire inserted into the center of the optical fiber cable as a tensile strength wire (Proc.
, Engineering xmz, 70168. No 10.1tpsa
).

However, since this method uses steel wire as a signal line, transmission loss is large, making it unsuitable for long-distance transmission lines. To apply this to a long-distance system, it is necessary to arrange a large number of repeater amplifiers, which increases the scale of the repeaters and increases the
A power transmission system for supplying power to these relay amplifiers is required, which complicates the system and makes it uneconomical.

Mayu, the digital optical signal that transmits the main signal for communication,
It is possible to perform monitoring during operation by transmitting monitoring signals in a time-division manner. However, in order to do this, it is necessary to provide each regenerative repeater with equipment for correctly branching the main signal and the monitoring signal and for transmitting an information signal indicating the status in response. If the repeater is configured using a normal integrated circuit, the circuit scale of the repeater will increase and the power consumption of the repeater will increase, making it impossible to carry out a realistic design.

The present invention was made against this background, and has the following features: (1) It is possible to monitor 11 relay transmission lines in operation, (2) The scale of the circuit arranged in each regenerative repeater is small, ( 3
(4) It is an object of the present invention to provide an optical repeater transmission line monitoring method that consumes less power in each regenerative repeater and (4) can be applied to long-distance multiple repeaters.

The first aspect of the present invention is a circuit disposed in each regenerative repeater to identify whether a monitoring identification signal transmitted from the transmitting end in a time-division manner together with the main signal is addressed to the own device. includes a surface acoustic wave element provided with surface electrodes equal to or greater than the number of bits of the identification signal, and whose surface electrodes are wired in accordance with the identification signal of each device, and the output signal of this surface acoustic wave element The device is characterized in that it is configured to identify that its own device has been selected.

A second aspect of the present invention is that, in addition to the above configuration, a second surface acoustic wave element is provided with surface electrodes whose number is equal to or greater than the number of bits of an information signal representing the state of each device, and each surface electrode of this element. The device is characterized in that it includes a circuit that increases the potential in response to a signal representing the state of the device, and a circuit that time-divisionally inserts the output bit signal string of this device between the main signals.

Regarding the surface acoustic wave element (8AW), see Example 7, Journal of the Acoustical Society of Japan, Vol. 30, No. 10, P, 551-540.
, 1974 has a detailed description.

Hereinafter, a detailed explanation will be given using embodiment drawings.

FIG. 1 is a block diagram of the main parts of a regenerative repeater according to an embodiment of the present invention.

The fiber optic cable 1 is coupled to an opto-electrical FI converter 2 whose electrical output is applied to a decoder 4 via an equalizer 3. This output is further taken out via a decoding converter 5 which converts the NR2 signal into an RZ signal. Further, this output is amplified by a coupler 6 and a driver 7, and then an electro-optical converter 8
from there to the next section of optical fiber cable 9.

Timing circuit 10 separates a timing signal from the output signal of equalizer 3 and controls decoder 4 .

Here, in the configuration that characterizes the present invention, the output signal of the code converter 5 is branched and the first surface acoustic wave element (EIAV
) 11, and this element 11 identifies the selection of the own device. The output of this surface acoustic wave element 11 is given to a control circuit 15 via a waveform shaping circuit 12 and further via a delay circuit 13. On the other hand, the timing signal obtained by the timing circuit 10 is frequency-divided by the frequency divider circuit 16 and given to the control circuit 15.

Terminal 18 is an input terminal for a signal representing the internal state of the regenerative repeater. The contents include, for example, the bias state of the electro-optic converter 8, the temperature state of the electro-optic converter 8, the bias state of the opto-electric converter 2, the state of the automatic gain control voltage included in the equalizer 3, etc. Each of these is one or more bit signals or analog signals, which are supplied from a terminal 18 to a multiplexer 20 and multiplexed. The output of the multiplexer 20 is sequentially sampled by a sample holding circuit 21, digitized by an AD conversion circuit 22, and input to a holding circuit 23.

Multiplexer 20, sample holding circuit 21. The memory D conversion circuit 22 and the holding circuit 23 are controlled by the control circuit 15.

The contents of the holding circuit 23 are given to the second surface acoustic wave element (8mmW) 26 by the gate circuit 25, and sent as a serial signal to its output. The serial signal passes through the waveform shaping circuit 28, is synchronized with the signal from the timing circuit 10 in the synchronization circuit 29, and is inserted into the digital signal train as an information signal in a time division manner in the coupler 6.

FIG. 2 is a diagram showing a digital signal train of this optical relay transmission line. The main signal is a bit signal sequence modulated according to the communication content. 8v is the time slot allocated for monitoring,
Among them, ID represents an identification signal, and q represents the position of an information signal. - As an example, the main signal M is composed of 508 bits, #'i6 bits from the identification signal, and the information signal GIFilO bits, and is repeatedly transmitted every frame.

The i-specific signal is a signal transmitted from a transmission end (not shown) to this optical relay transmission line, and is a signal for identifying the regenerative repeater to be monitored. Assuming a 6-bit configuration as described above, 2' = 64 regenerative repeaters can be identified.

The information signal q is a signal generated by the regenerative repeater and transmitted toward the receiving end. This information signal q is the above-mentioned identification signal I.
The regenerative repeater identified by D transmits in response to this identification signal. Main signal MFi is a signal modulated by the communication content transmitted from the transmitting end to the receiving end.

FIG. 5 is a diagram showing an example of the configuration of the Hiro surface acoustic wave element 11.

This surface acoustic wave element 11 is of a code response type, and the example shown in this figure is such that when the code 1 1 0 1, 0 1 is input to the input crab N, a signal is sent to the limited output 0. It is constructed. For each electrode position or electrode,
A book with wiring corresponds to a bit signal "1", and a book without wiring corresponds to a bit signal "0".

This wiring is set for each regenerative repeater according to its identification signal.

As a result, a signal is sent to the output OUT only when the identification signal of the own device is received.

FIG. 4 is a diagram showing a signal waveform (1)) in which the surface acoustic wave element 11 responds to the digital signal sequence -).

FIG. 5 is a diagram showing another structural example of the butterfly surface acoustic wave element.

The structure described above is simple, but if the main signal M or information signal Q happens to have the same combination of digital signal strings as the identification signal IQ of the own device, the output will be activated in response to this combination. There is a possibility that the data will be sent and malfunction. In order to avoid this, FIG. 5 shows that the surface acoustic wave element 11 is set to have a length of two frames (2fR) or more of the digital signal train.
It is configured to send an output signal when the identification signal Q is repeatedly detected two or more times.

Figure 6 is an explanatory diagram of its operation.
When the frame repetition period is TR, the output signal body) is sent to the surface acoustic wave element 11 only when the same identification code is sent again as the identification signal ID after time T8.

FIG. 7 shows an example in which a similar operation is implemented using a logic circuit, in which the output of the surface acoustic wave element 11 is divided into two parts, and one is connected to the delay circuit 3.
3, the signal is delayed by the time TR, and a gate circuit 32 performs an AND operation with a signal without delay to obtain a detection output.

, the possibility of false detection is similarly reduced.

FIG. 8 Line gate circuit 25 and second surface acoustic wave element 2
6 is a diagram showing a configuration example of No. 6; FIG. The surface acoustic wave element 26 has surface electrodes whose number is equal to or greater than the number of bits of the information signal q, and a potential is applied to each electrode from the gate circuit 25. Gate circuit 2
Each of the switching circuits 5 is opened and closed in accordance with a signal representing the state of the regenerative repeater at that time. As a result, a signal representing the state is sent to the output of the surface acoustic wave element 26 as a digital signal train.

Figure 9 is an explanatory diagram of its operation, and shows the input trigger signal ←
) is given, in response, the surface acoustic wave element 2
The output digital signal sequence (b) from 6 is 11000
・・・・・・・・・ Indicates the sent state as shown in 1. The pulse interval of this signal train is configured to exactly match the pulse interval of the digital signal train of the transmission line.

Returning to FIG. 1, this output signal train is generated by the waveform shaping circuit 28.
The information signal Q' is shaped into a waveform by the synchronizing circuit 29, and then sent out from the coupler 6.

The contents of the holding circuit 23 are reset by the output of the delay circuit 13 and updated to new contents under the control of the control circuit 15.

FIG. 10 is a time chart showing the overall operation of the apparatus according to the embodiment of the present invention. Figure 10-) to (e)FiX in Figure 1
The operating waveforms of points (,) to (e) shown with marks are shown.

That is, FIG. 10(a) is the input signal to the F1 surface acoustic wave element 110, and the output signal is output in response to the identification signal.
is sending out signals 81, 82... The contents of the holding circuit 23 are reset (8) or reset in synchronization with this. By the above-described operation, the information signal @) is sent out from the second surface acoustic wave element 26. This is passed through the coupler 6 into the digital signal train.
It is inserted as an information signal q as shown in Figure (e).

As described above, according to the present invention, surface acoustic wave elements are used to identify regenerative repeaters.

This is an excellent feature in that the circuit configuration is significantly simplified compared to the case where a memory element for this identification is provided in a general digital logic circuit, and the power consumption for this purpose is extremely small. There is. Furthermore, regenerative repeaters are suitable for mass production because they can be distinguished from others by simply setting the connections of the surface acoustic wave elements individually.

Furthermore, by using surface acoustic wave elements for sending out information signals, the companion logic circuit can be simplified and power consumption can be reduced.

By implementing the present invention, it becomes possible to individually identify and monitor regenerative repeaters from a distance during operation.
This eliminates the need to set up a backup line, improves the operating rate of the system, and is extremely advantageous in terms of system design and operation.

The system of the present invention is particularly effective when implemented in a submarine optical fiber system.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a regenerative repeater according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of the configuration of a digital signal string. FIG. 3 is a diagram showing an example of the structure of a surface acoustic wave element. FIG. 4 is an explanatory diagram of the operation of the surface acoustic wave element. FIG. 5 is a diagram showing another structural example of a surface acoustic wave element. FIG. 6 is an explanatory diagram of the operation. FIG. 7 is a diagram showing an example of a circuit for preventing malfunction. FIG. 8 is a diagram showing a configuration example of a second surface acoustic wave element and a gate circuit. Figure 9 is an explanatory diagram of its operation. FIG. 10 is a time chart illustrating the operation of the regenerative repeater according to the embodiment of the present invention. 1.9... Optical fiber cable, 11... First surface acoustic wave element, 25... Gate circuit, 26... Second surface acoustic wave element. Patent Applicant Nippon Telegraph and Telephone Public Corporation Representative Patent Attorney Attorney Takashi M 2 times ji 3 times 4 times transferred 1 mouth 1 FI month 5 Figure, PIi! 36 Figure 1 Ryo 7 Kuchi'JP38 Ken Akira 9 Kuchi Ryo 10 Figure

Claims (2)

[Claims] (1) An optical relay transmission line in which a plurality of optical 7-IPA cables and regenerative repeaters are alternately connected in cascade to transmit digital optical signals, and the regenerative repeaters are individually identified at the transmitting end of this transmission line. comprising means for transmitting an identification signal consisting of a multi-bit digital code string to the regenerative repeater;
a first means for identifying a signal addressed to the own device among the identification signals; and a first means for transmitting an information signal consisting of a multi-bit digital code string representing the state of the regenerative repeater in response to the output of the means. and a means for receiving the information signal at the receiving end of the transmission path, wherein the first means is provided with electrode positions equal to or greater than the number of bits of the identification signal. The device includes a surface acoustic wave element wired to the electrode position in response to an identification signal for each device, and is configured to identify that the device itself has been selected by the output signal of the surface acoustic wave device. A method for monitoring an optical relay transmission line, which is characterized in that: (2) An optical repeater transmission line in which a plurality of optical fiber cables and regenerative repeaters are alternately connected in cascade to transmit digital optical signals, and the regenerative repeater is individually identified at the transmitting end of this transmission line. The regenerative repeater includes means for transmitting an identification signal consisting of a digital code string of multiple bits,
a first means for identifying a signal addressed to the own device among the identification signals; and a first means for transmitting an information signal consisting of a multi-bit digital code string representing the state of the regenerative repeater in response to the output of the means. and a means for receiving the information signal at the receiving end of the transmission path, wherein the first means is provided with electrode positions equal to or greater than the number of bits of the identification signal, and each Wiring is provided to the electrode position in response to an identification signal for each device, and includes nine elastic surface wrinkle elements, and is configured to identify that the own device has been selected by the output signal of this surface acoustic wave element, The second means is configured to include surface electrodes whose number is equal to or greater than the number of bits of the information signal, and to apply a potential to the surface electrodes corresponding to the second surface acoustic wave element and the plurality of bits representing the state. 1. A monitoring method for an optical relay transmission line, comprising: a gate circuit;