CN107919908A - A kind of optical module receiving terminal sensitivity test system and its test method - Google Patents
A kind of optical module receiving terminal sensitivity test system and its test method Download PDFInfo
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- CN107919908A CN107919908A CN201711482653.8A CN201711482653A CN107919908A CN 107919908 A CN107919908 A CN 107919908A CN 201711482653 A CN201711482653 A CN 201711482653A CN 107919908 A CN107919908 A CN 107919908A
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- optical
- receiving terminal
- error detector
- optical module
- module receiving
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- 230000003287 optical effect Effects 0.000 title claims abstract description 122
- 238000012360 testing method Methods 0.000 title claims abstract description 48
- 230000035945 sensitivity Effects 0.000 title claims abstract description 36
- 238000010998 test method Methods 0.000 title claims abstract description 13
- 238000004891 communication Methods 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 3
- 238000012544 monitoring process Methods 0.000 claims description 3
- 230000008054 signal transmission Effects 0.000 claims description 3
- 238000001514 detection method Methods 0.000 claims description 2
- 238000012545 processing Methods 0.000 claims description 2
- 210000004556 brain Anatomy 0.000 claims 1
- 230000007423 decrease Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
- H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal
- H04B10/0795—Performance monitoring; Measurement of transmission parameters
- H04B10/07953—Monitoring or measuring OSNR, BER or Q
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B10/00—Transmission systems employing electromagnetic waves other than radio-waves, e.g. infrared, visible or ultraviolet light, or employing corpuscular radiation, e.g. quantum communication
- H04B10/07—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems
- H04B10/075—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal
- H04B10/079—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using an in-service signal using measurements of the data signal
- H04B10/0799—Monitoring line transmitter or line receiver equipment
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Optical Communication System (AREA)
Abstract
The invention discloses a kind of optical module receiving terminal sensitivity test system and its test method, its main feature is that the system is made of host computer computer with Error Detector and optical attenuator, the host computer computer is connected with Error Detector and optical attenuator；The Error Detector and optical attenuator carry out sensitivity test by the upper computer software for being arranged on host computer computer to optical module, its test method includes：The setting of Error Detector and optical attenuator, read error code and carry out the relation of linear fit lg (lg (BER)) and optical power value.The present invention is simple with equipment compared with prior art, easy to operate, quick, substantially increases the efficiency and accuracy of optical module receiving terminal sensitivity test, realizes the automatic test of optical module production.
Description
Technical field
It is especially a kind of to be used for the rapid automatized survey of optical module receiving terminal sensitivity the present invention relates to optical module technical field
Test system and its test method.
Background technology
The test of optical module receiving terminal sensitivity is to produce continuous or burst ratio with pattern generator transmitting end module
For special rate as information source data, receiving terminal receive the bit stream of communication system output, and the bit for exporting with sending is flowed into
Row compares, and completes the test of the bit error rate, then according to the size of the bit error rate, to adjust the size of received optical power, finally obtains
Take the information of sensitivity.
At present, optical module sensitivity test is first to adjust optical attenuator, power setting will be received to certain numerical value, from by mistake
The information of the code instrument observation bit error rate, if the bit error rate is zero, increase decay, untill there is error code, records light at this time
Module received optical power is sensitivity.If the bit error rate is not zero, decay is reduced, when the bit error rate is 10-12, records this
When optical module received optical power value be just sensitivity.
The bit error rate is strict controlled in 10- by the test method work efficiency and precision of the prior art all than relatively low in test
12 be a veryer long and difficult to realize process, causes the test of receiving terminal sensitivity time-consuming and laborious.
The content of the invention
The purpose of the present invention is in view of the deficiencies of the prior art and design a kind of optical module receiving terminal sensitivity test system
System and its test method, using the test system of Error Detector and optical attenuator composition, light is controlled by being arranged on upper computer software
The pad value of attenuator, obtains five groups of difference luminous powers（AOP）Under ber value（BER）, by AOP and log（-（BER））'s
Relation carries out linear fit, so as to derive that the bit error rate corresponds to optical power value under 10-12, which is the spirit of optical module receiving terminal
Sensitivity value, substantially increases the efficiency and accuracy of optical module receiving terminal sensitivity test, realizes the automation of optical module production
Test.
The object of the present invention is achieved like this：A kind of optical module receiving terminal sensitivity test system, its main feature is that the survey
Test system is made of host computer computer with Error Detector and optical attenuator, and the host computer computer connects with Error Detector and optical attenuator
Connect；The Error Detector and optical attenuator carry out sensitivity test by the upper computer software for being arranged on host computer computer to optical module.
The Error Detector includes at least differential signal transmission channel and all the way differential signal receiving channel all the way, and Error Detector
Operating rate and pattern control is set, adjusted and run by upper computer software.
The operation wavelength of the optical attenuator, initial attenuation value are set by upper computer software, and control declining for optical attenuator
Subtract step-length, and read the optical power value from the outgoing of optical attenuator OUT terminal.
The Error Detector is equipped with serial communication, USB or RS232 serial communication interfaces, is set and read by serial communication protocol
Take the working status of error code and detect current error code status.
The optical attenuator includes an optical input IN and light output mouth an OUT, the light output mouth OUT are equipped with light
Power monitoring and serial communication, USB or RS232 communication interfaces, set pad value by serial communication and read light output mouth OUT
Optical power value.
A kind of test method of optical module receiving terminal sensitivity test system, its main feature is that this method comprises the following steps：
（One）, Error Detector set
Before the sensitive test of optical module receiving terminal, according to the model of tested optical module, speed of the upper computer software to Error Detector
Whether rate and pattern are configured, correct by inquiring about button inquiry Error Detector current setting state.
（Two）, optical attenuator set
Before the sensitive test of optical module receiving terminal, the work according to the model of tested optical module and upper computer software to optical attenuator
Make wavelength and initial attenuation value is configured, it is whether correct by inquiring about button inquiry optical attenuator current setting state.
（Three）, operation Error Detector
Click on Error Detector to bring into operation, optical attenuator is increased with step-length 1dB and decayed.
（Four）, read error code
Read whether Error Detector receiving terminal has error code after decay every time, if produced without error code, repeat step（Three）,
Then carried out in the steps below if error code produces.
（Five）, attenuation steps
The step-length that optical attenuator is decayed is reduced to 0.3dB, records the outgoing luminous power and error code of attenuator output terminal OUT at this time
The bit error rate (BER) of instrument, repeats the step 5 time, records corresponding difference ber value (BER) under different optical power values.
（Six）, sensitivity calculating
The relation of linear fit lg (- lg (BER)) and optical power value, by the equation of fitting a straight line, calculate in BER=10-12
When corresponding optical power value, calculate gained be receiving terminal Sensitirity va1ue, repeat step（Two）~（Six）, it is all until completing
The test of channel sensitivity value.
The upper computer software is formed by " Labview " software programming, and the communication interface of host computer computer and Error Detector is
The communication interface of RS232 interface, host computer computer and optical attenuator is LAN interface.
The initial attenuation value is determined according to the difference of the optical power value of transmitting terminal and the Sensitirity va1ue of receiving terminal, it is general just
Beginning pad value is smaller 2~3dB than difference.
The bit error rate needs to be zeroed out processing to the number of bit errors and error code sum of the Error Detector passage before reading,
Prevent from reading the exception of result.
The attenuation steps 0.3dB can be finely adjusted according to the height of Error Detector speed.
The present invention is simple with equipment compared with prior art, easy to operate, quick, substantially increases optical module receiving terminal
The efficiency and accuracy of sensitivity test, realize the automatic test of optical module production.
Brief description of the drawings
Fig. 1 is the system schematic of the present invention；
Fig. 2 specifically uses schematic diagram for the present invention；
Fig. 3 is the soft work flow diagram of host computer.
Embodiment
Refering to attached drawing 1, the present invention is made of host computer computer 1 and Error Detector 2 and optical attenuator 3, the host computer computer 1
It is connected with Error Detector 2 and optical attenuator 3；The Error Detector 2 and optical attenuator 3 are soft by the host computer for being arranged on host computer computer 1
Part carries out sensitivity test to optical module；The Error Detector 2 includes at least differential signal transmission channel all the way and difference is believed all the way
Number receiving channel, and the operating rate of Error Detector 2 and pattern are set and adjusted by upper computer software and control is run；The light
The operation wavelength of attenuator 3, initial attenuation value are set by upper computer software, and control the attenuation steps of optical attenuator 3, and are read
Take the optical power value for bringing out and penetrating from optical attenuator 3OUT；The Error Detector 2 is equipped with serial communication, USB or RS232 serial communications connect
Mouthful, the working status for reading error code is set by serial communication protocol and detects current error code status；The optical attenuator 3 wraps
Optical power monitoring and serial communication, USB are equipped with containing an optical input IN and light output mouth an OUT, the light output mouth OUT
Or RS232 communication interfaces, pad value is set by serial communication and reads the optical power value of light output mouth OUT.
Below by taking concrete operations as an example, the invention will be further described.
Embodiment 1
Refering to attached drawing 2, test system of the invention includes：Error Detector 2, optical attenuator 3 and host computer computer 1, Error Detector 2 and light
Attenuator 3 is connected by serial communication interface with host computer computer 1.According to the model of tested optical module 4 before test, it is necessary to
Wavelength, initial attenuation value to the pattern of Error Detector 2, speed and optical attenuator are correctly set.
T+ the and T- ends of Error Detector 2 are connected with the P ends of standard test of light source plate 5 and N-terminal respectively, by standard test of light source
Plate 5 is loaded with the passage of signal, and is connected by optical patchcord with the input terminal IN of optical attenuator 3, the output terminal of optical attenuator 3
OUT is connected by optical patchcord with the receiving channel to be tested of tested optical module 4, is tested the corresponding P ends of optical module 4 and N-terminal point
R+, R- not with Error Detector 2 are connected.Optical patchcord needs determine that the selection of 850nm wavelength is more according to the operation wavelength of module
Mould wire jumper, the selection single mode wire jumper of 1310nm or 1550nm wavelength.
Refering to attached drawing 3, it is as follows that the upper computer software for being arranged on host computer computer 1 performs step：
Step 1, the setting of Error Detector 2：Before the sensitive test of optical module receiving terminal, it is necessary to according to the model of product to error code
The speed and pattern of instrument 2 are configured, while setting state that also can be current to Error Detector 2 is inquired about.
Step 2, the setting of optical attenuator 3：, it is necessary to model according to product before the sensitive test of optical module receiving terminal
The operation wavelength and initial attenuation value of optical attenuator 3 are configured, while current setting state can also be inquired about.
Step 3, clicks on Error Detector and brings into operation.
Step 4, optical attenuator 3 is increased with step-length 1dB and is decayed, and whether the receiving terminal of detection Error Detector 2 after decaying every time
There is error code.
Step 5, if produced without error code, repeats step 4, if error code produces, then in the steps below
Operated.
Step 6, be reduced to 0.3dB by the step-length that optical attenuator is decayed, and optical attenuator delivery outlet OUT goes out record at this time
Penetrate luminous power and the bit error rate (BER) of Error Detector.
Step 7, above-mentioned steps six repeat five times.
Step 8, passes through corresponding different ber value (BER) under five different optical power values, linear fit lg (- lg
(BER)) with the relation of optical power value.
Step 9, by the relation value of linear fit, calculates the optical power value in BER=10-12, gained calculated value is
For the Sensitirity va1ue of receiving terminal.
Step 10, repeats step 2~eight, the test until completing all channel sensitivity values.
Simply the present invention is further illustrated above, and is not used to limitation this patent, and all is equivalence enforcement of the present invention,
It is intended to be limited solely by within the right of this patent.
Claims (10)
1. a kind of optical module receiving terminal sensitivity test system, it is characterised in that the test system is by host computer computer and Error Detector
Formed with optical attenuator, the host computer computer is connected with Error Detector and optical attenuator；The Error Detector and optical attenuator are by setting
The upper computer software put in host computer computer carries out sensitivity test to optical module.
2. optical module receiving terminal sensitivity test system according to claim 1, it is characterised in that the Error Detector at least wraps
Containing differential signal transmission channel and all the way differential signal receiving channel all the way, and the operating rate of Error Detector and pattern are by host computer
Software design patterns, adjustment and operation control.
3. optical module receiving terminal sensitivity test system according to claim 1, it is characterised in that the work of the optical attenuator
Make wavelength, initial attenuation value is set by upper computer software, and control the attenuation steps of optical attenuator, and read from optical attenuator
The optical power value of OUT terminal outgoing.
4. optical module receiving terminal sensitivity test system according to claim 1 or claim 2, it is characterised in that the Error Detector is equipped with
Serial communication, USB or RS232 serial communication interfaces, working status and the detection for reading error code are set by serial communication protocol
Current error code status.
5. according to the optical module receiving terminal sensitivity test system of claim 1 or 3, it is characterised in that the optical attenuator bag
Optical power monitoring and serial communication, USB are equipped with containing an optical input IN and light output mouth an OUT, the light output mouth OUT
Or RS232 communication interfaces, pad value is set by serial communication and reads the optical power value of light output mouth OUT.
A kind of 6. test method of optical module receiving terminal sensitivity test system described in claim 1, it is characterised in that this method
Carry out in the steps below：
（One）, Error Detector set
Before the sensitive test of optical module receiving terminal, according to the model of tested optical module, speed of the upper computer software to Error Detector
Whether rate and pattern are configured, and correct by inquiring about button inquiry Error Detector current setting state；
Optical attenuator is set
Before the sensitive test of optical module receiving terminal, according to the model of tested optical module, work of the upper computer software to optical attenuator
Make wavelength and initial attenuation value is configured, it is whether correct by inquiring about button inquiry optical attenuator current setting state；
（Three）, operation Error Detector
Click on Error Detector to bring into operation, optical attenuator is increased with step-length 1dB and decayed；
（Four）, read error code
Read whether Error Detector receiving terminal has error code after decay every time, if produced without error code, repeat step（Three）,
Performed in the steps below if error code produces then to hold；
（Five）, attenuation steps
The step-length that optical attenuator is decayed is reduced to 0.3dB, records the outgoing luminous power and error code of attenuator output terminal OUT at this time
The bit error rate (BER) of instrument, repeats the step 5 time, records corresponding difference ber value (BER) under different optical power values；
The calculating linear fit lg (- lg (BER)) of sensitivity and the relation of optical power value, by fitting a straight line equation, calculate
The corresponding optical power value in BER=10-12, calculates the Sensitirity va1ue that gained is receiving terminal, repeat step（Two）~（Six）,
Test until completing all channel sensitivity values.
7. the test method of optical module receiving terminal sensitivity test system according to claim 6, it is characterised in that on described
Position machine software is formed by " Labview " software programming, and the communication interface of host computer computer and Error Detector is RS232 interface, upper
The communication interface of electromechanical brain and optical attenuator is LAN interface.
8. the test method of optical module receiving terminal sensitivity test system according to claim 6, it is characterised in that described first
Beginning pad value is determined according to the difference of transmitting terminal optical power value and receiving terminal Sensitirity va1ue, and the initial attenuation value is smaller than difference by 2
~3dB.
9. the test method of optical module receiving terminal sensitivity test system according to claim 6, it is characterised in that the mistake
Code check needs to be zeroed out processing to the number of bit errors and error code sum of the Error Detector passage before reading, to prevent from reading the different of result
Often.
10. the test method of optical module receiving terminal sensitivity test system according to claim 6, it is characterised in that described to decline
Subtracting step-length 0.3dB can be finely adjusted according to the height of Error Detector speed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201711482653.8A CN107919908A (en) | 2017-12-29 | 2017-12-29 | A kind of optical module receiving terminal sensitivity test system and its test method |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109450732A (en) * | 2018-11-16 | 2019-03-08 | 郑州云海信息技术有限公司 | A kind of test method, device, terminal and the storage medium of analog optical fiber on-off |
| CN113541778A (en) * | 2021-07-13 | 2021-10-22 | 深圳恒朴光电科技有限公司 | Automatic testing system and method for optical module |
| CN113839710A (en) * | 2021-08-26 | 2021-12-24 | 吴通光电智联科技(武汉)有限公司 | Method, device and system for testing receiving sensitivity value of optical module |
| CN114285478A (en) * | 2021-12-22 | 2022-04-05 | 上海航天科工电器研究院有限公司 | Optical transceiver and transmission method based on USB2.0 signal transmission |
| CN116094589A (en) * | 2023-01-12 | 2023-05-09 | 武汉英飞光创科技有限公司 | Device and method for evaluating performance of equalizer of optical module |
| CN118074800A (en) * | 2024-03-28 | 2024-05-24 | 中国人民解放军国防科技大学 | Automatic testing method and system for optical terminal receiving sensitivity |
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| CN101908927A (en) * | 2010-06-17 | 2010-12-08 | 成都优博创技术有限公司 | Method for extrapolating and testing sensitivity of light receiving device |
| CN102299739A (en) * | 2011-07-29 | 2011-12-28 | 深圳市国扬通信股份有限公司 | Test method for SFP (small form-factor pluggable) module and test terminal thereof |
| CN106160848A (en) * | 2015-03-24 | 2016-11-23 | 中兴通讯股份有限公司 | The error-code testing method of a kind of multichannel system, device and system |
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| US5546325A (en) * | 1993-02-04 | 1996-08-13 | International Business Machines Corporation | Automated system, and corresponding method, for testing electro-optic modules |
| CN101908927A (en) * | 2010-06-17 | 2010-12-08 | 成都优博创技术有限公司 | Method for extrapolating and testing sensitivity of light receiving device |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109450732A (en) * | 2018-11-16 | 2019-03-08 | 郑州云海信息技术有限公司 | A kind of test method, device, terminal and the storage medium of analog optical fiber on-off |
| CN113541778A (en) * | 2021-07-13 | 2021-10-22 | 深圳恒朴光电科技有限公司 | Automatic testing system and method for optical module |
| CN113839710A (en) * | 2021-08-26 | 2021-12-24 | 吴通光电智联科技(武汉)有限公司 | Method, device and system for testing receiving sensitivity value of optical module |
| CN114285478A (en) * | 2021-12-22 | 2022-04-05 | 上海航天科工电器研究院有限公司 | Optical transceiver and transmission method based on USB2.0 signal transmission |
| CN116094589A (en) * | 2023-01-12 | 2023-05-09 | 武汉英飞光创科技有限公司 | Device and method for evaluating performance of equalizer of optical module |
| CN118074800A (en) * | 2024-03-28 | 2024-05-24 | 中国人民解放军国防科技大学 | Automatic testing method and system for optical terminal receiving sensitivity |
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Application publication date: 20180417 |