WO2011140792A1

WO2011140792A1 - Method and device for automatic power reduction (apr) protection

Info

Publication number: WO2011140792A1
Application number: PCT/CN2010/078476
Authority: WO
Inventors: 张明超
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-05-12
Filing date: 2010-11-05
Publication date: 2011-11-17
Also published as: CN101882958A; CN101882958B

Abstract

The present invention discloses a method and device for Automatic Power Reduction (APR) protection, and said device comprises: an optical coupler, used for coupling part of the optical power at the input end of a card of a target station to another card of the target station; another card, used for detecting whether the part of the optical power is below a threshold, and if yes, then requesting a source station to reduce the output optical power. According to the technical solutions provided in the present invention, the problem that using a signaling interaction mode to reduce the optical power in the related technologies has relatively low reliability and restricted speed is solved, and therefore the reliability and the execution speed of the APR process can be improved.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication hub or, in particular, to an optical power reduction (APR) protection method and apparatus. BACKGROUND In an optical communication system, an optical cable is cut, a device fails, or an optical connector is pulled out, and the optical power is lost. For the sake of human eye safety, optical power is lost in one optical transmission section of the main optical channel. In this case, the system needs to provide an automatic optical power reduction (APR) process. In order to recover the system more easily after the link is reconnected, it is necessary to consider implementing an automatic (or manual) restart process. When the optical signals of all the main optical channels are detected to be lost, the Wavelength Division Multiplexing (WDM)/Optical Transport Network (OTN) system starts the APR process and closes the affected All the amplifiers in the Optical Transport Section (OTS) section; when the signal is recovered, the operation of the Line Amplifier (LA) can be restored. This ensures that the optical power in the fiber is within the safety level when it is turned off. The APR technology process of the optical transmission system must be operated continuously, that is, it cannot be turned off, otherwise the danger level will be too high. The principle of the APR process is described below in conjunction with FIG. When the A-point cable is broken, the optical transmission segment signal continuity loss (LOC-OTS) is detected at the receiving port R2, which causes the output power of the T2 transmitting port to decrease; also causes the LOC-OTS at the receiving port R1. Thereby the output power at the transmission port T1 is reduced. This ensures that the optical power in the OTS segment where the fault A is located is at a safe level. In the related art, when the optical signal loss is detected at R2, the lost information is reported to the APR controller in the system, and the APR controller sends an APR command to reduce the output optical power at T2. In this implementation, signaling interaction is required, so reliability is low and speed is limited. SUMMARY OF THE INVENTION The present invention is directed to providing an APR protection method and apparatus to solve at least one of the above problems, in which the optical power is reduced in a manner of signaling interaction in the related art, and the reliability is low and the speed is limited. . According to one aspect of the invention, an automatic optical power reduction APR protection device is provided. An APR protection device according to the present invention includes: an optical coupler for coupling a portion of optical power to another board of a destination station at an input end of a card of a destination station; and another board for detecting whether a portion of the optical power is detected Below the threshold, if yes, the source site is requested to reduce the output optical power. According to another aspect of the present invention, an automatic optical power reduction APR protection method is provided. The APR protection method according to the present invention includes: coupling a portion of optical power to another board of the destination site at an input end of the board of the destination site; and detecting whether a portion of the optical power is below a threshold value, and if so, another A board requests the source site to reduce the output optical power. According to the present invention, an optical coupler is added at the end of the transmission fiber, and a part of the optical power is coupled to another board of the destination station for signal detection, which solves the problem of reducing optical power by using a signaling interaction method in the related art. The problem of lower speed and limited speed can improve reliability and speed of execution of the APR process. BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are set to illustrate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 1 is a schematic diagram of an APR process according to an embodiment of the present invention; FIG. 2 is a schematic structural diagram of an APR protection device according to an embodiment of the present invention; 4 is a schematic view showing the internal structure of the LA in the first embodiment of the present invention; FIG. 5 is a schematic view showing the internal structure of the LA in the second embodiment of the present invention; 6 is a flow chart of an APR protection method according to an embodiment of the present invention; FIG. 7 is a schematic structural view of an APR protection device incorporating a 1:99 optical coupler at the end of a transmission fiber according to an example of the present invention; A schematic diagram of the structure of an APR protection device incorporating a 5:95 optical coupler at the end of a transmission fiber in an inventive example. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict. 2 is a schematic structural view of an APR protection device according to an embodiment of the present invention. As shown in FIG. 2, the APR protection device mainly comprises: an optical coupler 20 and another board 22 (which may be the aforementioned optical line amplifier). The optical coupler 20 is configured to couple a part of the optical power to another board of the destination station at the input end of the board of the destination station; and another board 22 for detecting whether a part of the optical power is lower than a threshold, and if so, Then the source site is requested to lower the output optical power.上述With the above APR protection device, an optical coupler is added at the end of the transmission fiber, and a part of the optical power is coupled to another board of the destination station for signal detection, thereby avoiding signaling interaction between the controller and the LA in the related art, and improving Reliability and execution speed of the APR process. Preferably, the optical coupler 20 is further configured to divide the received optical power into two parts by using a predetermined splitting ratio, and couple a part of the optical power in the two parts to another board, and to combine the optical powers of the two parts. A larger portion is coupled to the board. As shown in FIG. 2, the APR protection device according to the embodiment of the present invention adds an optical coupler to the end of the optical fiber to be transmitted, and divides the optical signal into two paths, and continues to transmit along the path of the optical fiber. In the direction of transmission, the other way is to access the B-direction LA for optical signal detection. Among them, the line drawn by the arrow in the figure is the optical fiber, and the direction of the arrow is the direction of light transmission. It should be noted that, as shown in FIG. 2, an optical coupler may be added to the end of the B-to-light transmission fiber, and the optical signal is divided into two paths, one path continues to be transmitted in the transmission direction, and the other channel is connected to the A direction. Optical signal detection is performed in LA. The other board 22 mentioned above may be an optical line amplifier (LA), and in order to implement the present invention, a corresponding improvement to the LA is required. The internal functional modules of the LA are described below in conjunction with FIG. 3 is a block diagram showing the structure of an LA internal function module in accordance with a preferred embodiment of the present invention. As shown in FIG. 3, the LA may include two functional modules: a light detecting module 30 and an LA control module 32, wherein the light detecting module inside the LA sends the detection result (whether or not there is a phenomenon that the optical power signal is lost) to the LA. The control module, when detecting the loss of the optical signal, the LA control module controls the output power of the LA to be reduced to the safe power. The preferred internal structure of the LA will be described below with reference to FIGS. 4 and 5. Preferably, as shown in FIG. 4, LA may further include: a photoelectric conversion module 40 (for example, a photodiode) for converting the received optical power signal into an electrical signal and inputting to an analog to digital conversion circuit; analog to digital conversion The circuit 42 is configured to convert the received electrical signal into a digital signal and send it to the control module 44. The control module 44 is configured to identify, according to the digital signal, whether a portion of the optical power is lower than a threshold, and request the source station to reduce the output optical power. The photoelectric conversion module is not limited to a photodiode, and the photoelectric conversion module may also be other photoelectric conversion devices. Preferably, as shown in FIG. 5, the LA may further include: a photoelectric conversion module 50 for converting the received optical power signal into a level signal and inputting to the comparator; and a comparator 52 for receiving the received The level of the level signal is compared with the level threshold, and the output high level or low level signal is determined according to the comparison result, and output to the control module 54; the control module 54 is configured to identify according to the high level or low level signal Whether part of the optical power is below the threshold and request the source station to reduce the output optical power. 6 is a flow chart of an APR protection method according to an embodiment of the present invention. As shown in FIG. 6, the AP R protection method mainly includes the following processes: Step S602: Coupling a part of optical power to another board of the destination station at an input end of the board of the destination station; Step S604: Another board detection Whether part of the optical power is below the threshold, and if so, another board requests the source station to reduce the output optical power. By using the above APR protection method, the signaling interaction between the controller and the LA in the related art can be avoided, and the reliability and the execution speed of the APR process can be improved. Preferably, the above step S602 may further include the following processes: (1) the optical coupler divides the received optical power into two parts by a predetermined splitting ratio;

(2) The optocoupler couples a smaller portion of the optical power in the two sections to another board. In a preferred implementation, the optical coupler couples a portion of the optical power that is greater in both portions to the card. Through the above processing, it is possible to perform signal detection without affecting the normal transmission of the optical signal. Preferably, in step S604, another board detects whether a part of the optical power is below a threshold value, and may include the following processing:

(1) The photoelectric conversion module converts the received optical power signal into an electrical signal and inputs it to an analog-to-digital conversion circuit; (2) the analog-to-digital conversion circuit converts the received electrical signal into a digital signal and sends it to the control module;

(3) The control module identifies whether a part of the optical power is lower than a threshold according to the digital signal; wherein the photoelectric conversion module, the analog-to-digital conversion circuit, and the control module are included in the other board. Preferably, in step S604, another board detects whether a part of the optical power is below a threshold, and may further include the following processing:

(1) The photoelectric conversion module converts the received optical power signal into a level signal and inputs it to the comparator;

(2) the comparator compares the level of the received level signal with a level threshold, determines an output high level or low level signal according to the comparison result, and outputs the signal to the control module; (3) The control module identifies whether a part of the optical power is lower than a threshold according to the high level or low level signal; wherein the photoelectric conversion module, the comparator, and the control module are all included in another board. The above preferred implementation process will be described below with reference to FIGS. 7 and 8. Figure 7 is a block diagram showing the construction of an APR protection device incorporating a 1:99 optical coupler at the end of a transmission fiber in accordance with an embodiment of the present invention. As shown in Figure 7, the coupler uses a 1:99 optical power split ratio and 1% of the optical power enters the B-direction LA for detection. In the preferred implementation, the LA shown in Figure 4 can be used for detection and control. That is, 1% of the optical power enters the LA, and the optical power signal is converted into an electrical signal through the photodiode, and the electrical signal is sent to the analog-to-digital conversion circuit to be converted into a digital signal that the control module can recognize. The control module of LA determines whether the optical power signal is lost (ie, whether the optical power of the input LA is lower than the threshold), and if it is lost, the input optical power of the control LA decreases. In the preferred implementation, the LA shown in Figure 5 can also be used for detection and subsequent control. The optical power enters the LA, and the optical power signal is converted into an electrical signal through the photodiode. The electrical signal is sent to the comparator and compared with a fixed voltage V (ie, a threshold). If the voltage is lower than the voltage, the circuit outputs a chirp level. Above V, the output is high, and the output level signal is sent to the LA control module. LA determines whether to reduce the output optical power according to the high level. If the output is high, the original power output is maintained, and the output is low. Optical power output. Figure 8 is a block diagram showing the construction of an APR protection device incorporating a 5:95 optical coupler at the end of a transmission fiber in accordance with an embodiment of the present invention. As shown in Figure 8, the coupler uses a 5:95 optical power split ratio and 5% of the optical power enters the B-direction LA for detection. In the preferred implementation, the LA shown in Figure 4 can be used for detection and control. It is also possible to perform detection and subsequent control using the LA shown in FIG. The specific detection and control process has been mentioned above and will not be described here. In summary, with the above embodiments provided by the present invention, signaling interaction between the controller and the LA can be avoided under the premise of implementing the APR protection, and the reliability and the execution speed of the APR process can be improved. Moreover, the APR protection device according to the embodiment of the present invention is simple and practical, and is easy to implement. Obviously, those skilled in the art will appreciate that the various modules or steps of the present invention described above can be implemented with a general purpose computing device, which can be centralized on a single computing device, or distributed. Alternatively, on a network of computing devices, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, The steps shown or described may be performed in an order different than that herein, or they may be separately fabricated into individual integrated circuit modules, or a plurality of the modules or steps may be implemented as a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

An automatic optical power reduction APR protection device for use in a wavelength division system, characterized in that the device comprises:

An optical coupler for coupling a portion of the optical power to another board of the destination site at an input of the board of the destination site;

The other board is configured to detect whether the part of the optical power is lower than a threshold, and if yes, request the source station to reduce the output optical power.

2. Apparatus according to claim 1 wherein:

The optical coupler is further configured to divide the received optical power into two parts by using a predetermined splitting ratio, and couple a portion of the two parts with a smaller optical power to the other board, and the two A portion of the portion of the optical power that is relatively large is coupled to the board.

3. The device according to claim 1, wherein the other board comprises:

a photoelectric conversion module, configured to convert the received optical power signal into an electrical signal, and input the signal to the analog to digital conversion circuit; the analog to digital conversion circuit, configured to convert the received electrical signal into a digital signal, and send To the control module;

The control module is configured to identify, according to the digital signal, whether the part of the optical power is lower than the threshold, and request the source station to reduce the output optical power.

4. The device according to claim 1, wherein the other board comprises:

a photoelectric conversion module, configured to convert the received optical power signal into a level signal, and input the signal to the comparator;

The comparator is configured to compare the level of the received level signal with a level threshold, determine an output high level or low level signal according to the comparison result, and output the signal to the control module; And determining, according to the high level or low level signal, whether the part of the optical power is lower than the threshold, and requesting the source station to reduce the output optical power.

The device according to claim 3 or 4, wherein the photoelectric conversion module comprises: a photodiode.

6. An automatic optical power downgrading APR protection method for use in a wavelength division system, characterized in that the method comprises:

Coupling a portion of the optical power to another board of the destination site at an input of the board of the destination site;

The other board detects whether the portion of the optical power is below a threshold, and if so, the other board requests the source station to reduce the output of the optical power.

7. The method of claim 6 wherein the coupling of a portion of the optical power to the other of the destination stations comprises:

The optical coupler divides the received optical power into two parts by a predetermined splitting ratio; the optical coupler combines a portion of the two portions with a smaller optical power to the other board.

8. The method according to claim 7, further comprising:

The optocoupler couples a portion of the two portions of greater optical power to the card.

9. The method according to claim 6, wherein the detecting, by the other board, whether the part of the optical power is lower than a threshold comprises:

The photoelectric conversion module converts the received optical power signal into an electrical signal and inputs the signal to the analog to digital conversion circuit;

The analog to digital conversion circuit converts the received electrical signal into a digital signal and sends it to a control module;

The control module identifies, according to the digital signal, whether the portion of the optical power is lower than the threshold;

The photoelectric conversion module, the analog to digital conversion circuit, and the control module are included in the other board.

The method according to claim 6, wherein the detecting, by the other board, whether the part of the optical power is lower than a threshold comprises:

The photoelectric conversion module converts the received optical power signal into a level signal and inputs the signal to the comparator; The comparator compares the level of the received level signal with a level threshold, determines an output high level or low level signal according to the comparison result, and outputs the signal to the control module; a high level or low level signal identifying whether the portion of the optical power is below the threshold;

The photoelectric conversion module, the comparator, and the control module are all included in the other board.