CN101820320A - Method for controlling optical amplifier to carry out amplification treatment on optical signals and device thereof - Google Patents
Method for controlling optical amplifier to carry out amplification treatment on optical signals and device thereof Download PDFInfo
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- CN101820320A CN101820320A CN200910078923A CN200910078923A CN101820320A CN 101820320 A CN101820320 A CN 101820320A CN 200910078923 A CN200910078923 A CN 200910078923A CN 200910078923 A CN200910078923 A CN 200910078923A CN 101820320 A CN101820320 A CN 101820320A
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Abstract
The invention discloses a method for controlling an optical amplifier to carry out amplification treatment on optical signals and a device thereof, which are used for improving the transmission performance of the optical signals of a passive optical network PON system, wherein the method comprises the following steps: detecting the power of the input optical signals when the optical amplifier adopts the constant gain amplification way for carrying out the amplification treatment on the input optical signals; and controlling the optical amplifier to switch from the constant gain amplification way to the constant pump amplification way for carrying out the amplification treatment on the input optical signals when detects that the power of the input optical signals is in oscillation.
Description
Technical field
The present invention relates to the optical communication technique field, especially relate to a kind of image intensifer carries out processing and amplifying to light signal method and device thereof of controlling.
Background technology
EPON (PON, Passive Optical Network) technology is to realize that optical fiber is to object (FTTx, Fiber To The X) mainstream technology, as shown in Figure 1, for typical PON network structure in the prior art, specifically comprise optical line terminal (OLT, Optical Line Terminal) 10, Optical Distribution Network (ODN, Optical Distribution Network) 20 and optical network unit (ONU, OpticalNetwork Unit) 30.Concrete, " passive " promptly is meant and do not comprise any active electronic device and power supply among the ODN 20, all be made up of passive devices such as optical fiber and optical branching devices.
Along with the increase gradually of optical signal transmission distance and the introducing of multiplexer/demultiplexer, the decay of light signal in transmission course is also more and more obvious among the PON, in order to reduce the decay of light signal in transmission course among the PON, need between OLT and ODN, introduce erbium-doped fiber amplifier (EDFA, Erbium-dopedFiber Amplifier), in order to the light signal that transmits among the PON is compensated, to remedy signal attenuation.
As shown in Figure 2, be the PON network structure of PON of future generation (NG-PON) and gigabit PON (GPON) coexistence, wherein include EDFA in amplification and the processing module (AmPM, Amplifies Process Module).As shown in Figure 3, for the composition structural representation of amplification with processing module inside, specifically comprise EDFA 1 and EDFA 2, concrete EDFA 1 is used to amplify the downlink optical signal of OLT to ONU, and EDFA2 is used to amplify the uplink optical signal of ONU to OLT.
In the PON system, can be with a plurality of ONU (32,64 or 128 etc.) on each wavelength, the ONU on the same wavelength adopts time division multiplexing (TDM, Time Division Multiplexing) mode to share optical-fibre channel, and ONU launches uplink optical signal with burst form.
At present, EDFA adopts permanent power output, permanent pumping and three kinds of amplification modes of permanent gain that light signal is carried out processing and amplifying usually.Generally EDFA adopts permanent gain amplification mode that light signal is carried out processing and amplifying more, wherein adopt permanent gain amplification mode to the detailed process that light signal carries out processing and amplifying to be: EDFA is by the feedback circuit of self inside, constantly detect the power of the input optical signal of self, and according to testing result, to the laggard line output of the constant multiple of the power amplification of input optical signal.
But because ONU adopts burst form emission uplink optical signal usually, will cause occurring such a case: the response frequency of the feedback circuit of the change frequency of burst luminous signal and EDFA inside is near (response frequency of the feedback circuit of EDFA inside is approximately the kHz magnitude, corresponding feedback cycle probably is the ms magnitude) time, EDFA just might judge the power of the input optical signal of self accurately, therefore can cause the serious vibration of the power of output light signal, to have a strong impact on the optical signal transmission performance of PON system thus, cause the generation of a large amount of error codes in the transmitting optical signal.
Summary of the invention
The embodiment of the invention provides a kind of image intensifer of controlling that light signal is carried out the method and the device thereof of processing and amplifying, to improve the optical signal transmission performance of PON system.
For addressing the above problem, the embodiment of the invention provides a kind of image intensifer carries out processing and amplifying to light signal method of controlling, comprise: when image intensifer adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, detect the power of described input optical signal; When vibration took place the power that detects input optical signal, the control image intensifer adopted the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting permanent gain amplification mode to switch to.
The embodiment of the invention is also corresponding provides a kind of image intensifer carries out processing and amplifying to light signal device of controlling, comprise the input optical power detecting unit, be used for when image intensifer adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, detecting the power of described input optical signal; Control unit is used for when the input optical power detecting unit detects the power generation vibration of input optical signal, and the control image intensifer adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting the permanent amplification mode that gains to switch to.
When the embodiment of the invention is carried out processing and amplifying by adopt permanent gain amplification mode at image intensifer (for example EDFA) to input optical signal, the change frequency of judging the light signal be input to image intensifer whether with image intensifer in the response frequency of feedback circuit approaching, and judged result be near the time, the control image intensifer adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting permanent gain amplification mode to switch to, can avoid thus when the response frequency of feedback circuit in the change frequency of the light signal that is input to image intensifer and the image intensifer near the time, image intensifer possibly can't be judged the power of the input optical signal of self accurately, if also continue to adopt permanent gain amplification mode this moment input optical signal is carried out processing and amplifying, will cause the serious oscillation problem of output optical signal power, thereby influence the optical signal transmission performance of PON system.
Description of drawings
Below in conjunction with each accompanying drawing the specific implementation process of the embodiment of the invention is carried out more detailed elaboration, wherein in each accompanying drawing:
Fig. 1 is a typical PON network structure in the prior art;
Fig. 2 is the PON network structure of NG-PON and GPON coexistence;
Fig. 3 is the composition structural representation of amplification with processing module inside;
Fig. 4 is the internal structure schematic diagram of EDFA in the embodiment of the invention;
The control EDFA that Fig. 5 proposes for the embodiment of the invention carries out the composition structured flowchart of the device of processing and amplifying to light signal.
Embodiment
The design philosophy of the embodiment of the invention is when image intensifer adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, the change frequency of judging the burst luminous signal be input to image intensifer whether with image intensifer in the response frequency of feedback circuit approaching, and under approaching situation, the control image intensifer adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting permanent gain amplification mode to switch to, thereby the response frequency of having avoided being input to feedback circuit in the change frequency of light signal of image intensifer and the image intensifer near the time, still continue to adopt permanent gain amplification mode that input optical signal is carried out processing and amplifying, may cause the output optical signal power to produce the problem of serious vibration, therefore guarantee the optical signal transmission performance of PON system preferably.
In the optical communication technique field, image intensifer adopts EDFA usually at present, thus the embodiment of the invention also to adopt EDFA here be that example elaborates, the image intensifer of other types is also within protection scope of the present invention certainly.
As shown in Figure 4, internal structure schematic diagram for EDFA in the embodiment of the invention, wherein EDFA comprises the amplification Control and Feedback circuit of partly being made up of input optical power test section, Output optical power test section and controller, and its middle controller can be controlled EDFA and specifically adopt permanent gain amplification mode or adopt permanent pumping to amplify mode or adopt the permanent power output mode of amplifying that input optical signal is carried out processing and amplifying.When change frequency that controller detects the burst luminous signal that is input to EDFA near EDFA in during the response frequency of feedback circuit, automatically EDFA is switched to permanent pumping to the amplification mode of input optical signal by perseverance gain amplification mode and amplifies mode.
Particularly, when EDFA adopts permanent gain amplification mode that the light signal that is input to EDFA is carried out processing and amplifying, here suppose that the perseverance gain that EDFA adopts is GO, then controller can be managed the power P 1 that 1 detection is input to the light signal of EDFA by PIN, launch the pump light of suitable power then by the control pump laser, the light signal that is input to EDFA is after the pump light of the suitable power of this pump laser emission amplifies, the power of the light signal of output EDFA will become P2, GO=P2/P1 under the normal condition, and P1 should keep constant.
Controller detects the power P 2 of the light signal of output EDFA by PIN pipe 3, and whether checking GO=PI/P2 sets up, if be false then adjust the power P 2 of the light signal of output EDFA by the power of adjusting pump laser emission pump light, set up up to above-mentioned formula GO=P1/P2, this adjustment process promptly constitutes the response frequency of EDFA internal feedback circuitry.
According to prior art, at the change frequency of the burst luminous signal that is input to EDFA during near the response frequency of EDFA internal feedback circuitry, the power P 1 that controller detects the light signal that is input to EDFA will have transient change, the power that promptly is input to the input optical signal of EDFA will vibrate, therefore after adopting pump light signals that input optical signal is amplified, the power P 2 of the light signal of EDFA output also will be vibrated, thereby cause output optical signal quality deterioration, so that influence the optical signal transmission performance of PON system.
In order to solve this problem that exists in the prior art, when the power P 1 that detects the light signal that is input to EDFA at controller in the embodiment of the invention has transient change, when vibration has taken place in the power that promptly detects the light signal that is input to EDFA, the change frequency of burst luminous signal of just determining to be input to EDFA is near the response frequency of EDFA internal feedback circuitry, automatically EDFA can be switched to permanent pumping to the amplification mode of input optical signal by perseverance gain amplification mode and amplify mode, thereby effectively avoided because the power of input optical signal vibrates, better prevent the quality deterioration of output light signal, improved the optical signal transmission performance of PON system.Otherwise,, will cause the power of output light signal to vibrate if also continue to adopt permanent gain amplification mode that input optical signal is carried out processing and amplifying.
The change frequency how its middle controller detects the burst luminous signal that is input to EDFA is readily appreciated that for a person skilled in the art near the response frequency of EDFA internal feedback circuitry, here only provide a kind of preferable detection mode, but when specifically implementing the embodiment of the invention, can also adopt other detection modes as the case may be:
Because when the change frequency of the burst luminous signal that is input to EDFA during near the response frequency of EDFA internal feedback circuitry, the power that is input to the burst luminous signal of EDFA will have transient change, the power that promptly is input to the burst luminous signal of EDFA will vibrate, and whether the change frequency that therefore can whether produce the burst luminous signal that vibration determines to be input to EDFA by the burst luminous signal that detection is input to EDFA is near the response frequency of EDFA internal feedback circuitry.Concrete testing process is as follows:
Controller is at the appointed time in the length, and the performance number of the burst luminous signal that is input to EDFA is carried out the detection of stipulated number; In detected performance number, the absolute value of difference of constant power level of adding up and be input to the burst luminous signal of EDFA surpasses the number of the performance number of defined threshold; When the individual numerical value that obtains when statistics reaches defined amount, can determine that then the power that detects the burst luminous signal that is input to EDFA produces vibration, promptly detects the response frequency of the change frequency of the burst luminous signal that is input to EDFA near the EDFA internal feedback circuitry.For example can set every 30ms carries out 20 times to the performance number of the light signal that is input to EDFA and detects, promptly in every 30ms, can detect the performance number P1 of 20 input optical signals, if there is the P1 value more than 10 in detected 20 P1 values, its with the constant power level difference of burst luminous signal that is input to EDFA more than 1dB, the change frequency of burst luminous signal that then can determine to be input to this moment EDFA is near the response frequency of EDFA internal feedback circuitry.
Controller is at the change frequency that detects the burst luminous signal that is input to EDFA during near the response frequency of EDFA internal feedback circuitry, before automatic amplification mode with EDFA switches to permanent pumping amplification mode by perseverance gain amplification mode, can so definite EDFA when adopting permanent gain amplification mode that input optical signal is carried out processing and amplifying, the concrete pump light signals of much power that adopts is carried out processing and amplifying to input optical signal, promptly determine the pump power values that is used for input optical signal is carried out the pump light signals of processing and amplifying that pump laser produces, when automatic control EDFA is switched to permanent pumping and is amplified mode by perseverance gain amplification mode the amplification mode of input optical signal, control EDFA switches to and adopts the permanent pumping of the pump power values of determining to amplify mode, continues the light signal that is input to EDFA is carried out processing and amplifying.
Particularly under following several situations, adopt the effect after the embodiment of the invention will more will be obvious:
1) during single wavelength transmission, increasing in the PON system has filter;
When 2) multichannel transmitted, the wavelength number of transmitting optical signal increased;
3) situation of EDFA cascade in the PON system.
Corresponding to the method for the above-mentioned proposition of the embodiment of the invention, also corresponding here proposition a kind of image intensifer of controlling light signal is carried out the device of processing and amplifying, be that EDFA is that example describes with this device here.As shown in Figure 5, light signal is carried out the composition structured flowchart of the device of processing and amplifying for the control image intensifer of embodiment of the invention proposition, comprising input optical power detecting unit 50, be used for when EDFA adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, detecting the power of the input optical signal that is input to EDFA; Control unit 52, be used for when input optical power detecting unit 50 detects the power generation vibration of the input optical signal that is input to EDFA, control EDFA adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting the permanent amplification mode that gains to switch to.
Generally speaking, when the change frequency of the burst luminous signal that is input to EDFA during near the response frequency of EDFA internal feedback circuitry, the power that is input to the burst luminous signal of EDFA will produce vibration, power generation vibration wherein how to judge the burst luminous signal that is input to EDFA is readily appreciated that to those skilled in the art, here only provide a kind of preferable implementation, but when specifically implementing the embodiment of the invention, can also adopt other implementations as the case may be:
Wherein require input optical power detecting unit 50 at the appointed time in the length, the performance number of the burst luminous signal that is input to EDFA is carried out the detection of stipulated number; And then control unit 52 can comprise the statistics subelement, be used for statistics in the afore mentioned rules time span, the number that surpasses the performance number of defined threshold in the input optical power detecting unit 50 detected performance numbers with the absolute value of the difference of the constant power level of the light signal that is input to EDFA, determine subelement, be used for when individual numerical value that statistics subelement statistics obtains reaches defined amount, the power of determining to detect the light signal that is input to EDFA vibrates, control sub unit, be used for when determining that subelement determines to detect the power generation vibration of the light signal that is input to EDFA, control EDFA adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting the permanent amplification mode that gains to switch to.
Preferably, when general EDFA adopts the permanent pumping mode of amplifying that the light signal that is input to EDFA is carried out processing and amplifying, all to adopt suitable pump power, therefore can also and then comprise power determining unit 54 in the device that the embodiment of the invention proposes, be used for when EDFA adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, determining the pump power that is used for input optical signal is carried out the pump light of pumping amplification that pump laser sends; Control unit 52 control EDFA amplify mode by the permanent pumping of the pump power that adopts permanent gain amplification mode to switch to adopt power determining unit 54 to determine like this, continue input optical signal is carried out processing and amplifying.
Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, if of the present invention these are revised and modification belongs within the scope of claim of the present invention and equivalent technologies thereof, then the present invention also is intended to comprise these changes and modification interior.
Claims (10)
1. control image intensifer light signal carried out the method for processing and amplifying for one kind, it is characterized in that, comprising:
When image intensifer adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, detect the power of described input optical signal;
When vibration took place the power that detects input optical signal, the control image intensifer adopted the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting permanent gain amplification mode to switch to.
2. the method for claim 1 is characterized in that, detects the power of described input optical signal, specifically comprises:
In the length, the performance number of described input optical signal is carried out the detection of stipulated number at the appointed time.
3. method as claimed in claim 2 is characterized in that, the described power that detects input optical signal vibrates, and specifically comprises:
Statistics surpasses the number of the performance number of defined threshold with the absolute value of the difference of the constant power level of described input optical signal in the detected performance number in described stipulated time length;
When the individual numerical value that obtains when statistics reaches defined amount, determine that the power that detects input optical signal vibrates.
4. the method for claim 1 is characterized in that, also comprises:
When image intensifer adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, be identified for input optical signal is carried out the pump power of the pump light of pumping amplification;
Described control image intensifer adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting permanent gain amplification mode to switch to, and specifically refers to:
The control image intensifer adopts the permanent pumping of the pump power of determining to amplify mode by adopting permanent gain amplification mode to switch to, and input optical signal is carried out processing and amplifying.
5. as the described method of 1～4 arbitrary claim, it is characterized in that described image intensifer is an Erbium-Doped Fiber Amplifier.
6. control image intensifer light signal carried out the device of processing and amplifying for one kind, it is characterized in that, comprising:
The input optical power detecting unit is used for detecting the power of described input optical signal when image intensifer adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying;
Control unit is used for when the input optical power detecting unit detects the power generation vibration of input optical signal, and the control image intensifer adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting the permanent amplification mode that gains to switch to.
7. device as claimed in claim 6 is characterized in that, described input optical power detecting unit in the length, carries out the detection of stipulated number at the appointed time to the performance number of described input optical signal.
8. device as claimed in claim 7 is characterized in that, described control unit specifically comprises:
The statistics subelement is used for statistics in described stipulated time length, surpasses the number of the performance number of defined threshold in the detected performance number of input optical power detecting unit with the absolute value of the difference of the constant power level of described input optical signal;
Determine subelement, be used for when individual numerical value that statistics subelement statistics obtains reaches defined amount, determining that the power that detects input optical signal vibrates;
Control sub unit is used for when determining that subelement is determined to detect the power generation vibration of input optical signal, and the control image intensifer adopts the permanent pumping mode of amplifying that input optical signal is carried out processing and amplifying by adopting the permanent amplification mode that gains to switch to.
9. device as claimed in claim 6, it is characterized in that, also comprise power determining unit, be used for when image intensifer adopts permanent gain amplification mode that input optical signal is carried out processing and amplifying, being identified for input optical signal is carried out the pump power of the pump light of pumping amplification; And
Control unit is controlled image intensifer and is adopted the permanent pumping of the definite pump power of power determining unit to amplify mode by adopting permanent gain amplification mode to switch to, and input optical signal is carried out processing and amplifying.
10. as the described device of 6～9 arbitrary claims, it is characterized in that described image intensifer is an Erbium-Doped Fiber Amplifier.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104704690A (en) * | 2012-12-05 | 2015-06-10 | 三菱电机株式会社 | Optical amplifier, wavelength multiplexing optical transmission system, and program |
| CN108834005A (en) * | 2018-07-23 | 2018-11-16 | 中天宽带技术有限公司 | A kind of passive optical fiber network system and its control method of power adjustable |
| CN109040866A (en) * | 2018-07-23 | 2018-12-18 | 中天宽带技术有限公司 | A kind of the optical network unit terminal and its control method of power adjustable |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6421170B1 (en) * | 1998-09-18 | 2002-07-16 | Corning Incorporated | Gain control and shaping of EDFAs via dual cavity gain control |
| CN1996800A (en) * | 2006-11-16 | 2007-07-11 | 无锡市中兴光电子技术有限公司 | Control device for the optical amplifier |
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2009
- 2009-02-27 CN CN2009100789238A patent/CN101820320B/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104704690A (en) * | 2012-12-05 | 2015-06-10 | 三菱电机株式会社 | Optical amplifier, wavelength multiplexing optical transmission system, and program |
| CN108834005A (en) * | 2018-07-23 | 2018-11-16 | 中天宽带技术有限公司 | A kind of passive optical fiber network system and its control method of power adjustable |
| CN109040866A (en) * | 2018-07-23 | 2018-12-18 | 中天宽带技术有限公司 | A kind of the optical network unit terminal and its control method of power adjustable |
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