Unlock instant, AI-driven research and patent intelligence for your innovation.
An optical time domain reflectometer and optical fiber testing method
What is Al technical title?
Al technical title is built by PatSnap Al team. It summarizes the technical point description of the patent document.
A technology of optical time domain reflectometer and optical fiber, which is applied to electrical components, electromagnetic wave transmission systems, transmission systems, etc., can solve the problems of high cost, high probability of post-pulse, high cooling requirements, etc., and achieve the effect of simple structure and easy realization
Active Publication Date: 2018-09-21
ZHEJIANG SHENZHOU QUANTUM NETWORK TECH CO LTD
View PDF5 Cites 0 Cited by
Summary
Abstract
Description
Claims
Application Information
AI Technical Summary
This helps you quickly interpret patents by identifying the three key elements:
Problems solved by technology
Method used
Benefits of technology
Problems solved by technology
However, at this time, the avalanche photodiode works in the Geiger-gated mode, and the after-pulse probability is high, so a long dead time needs to be set to eliminate the influence of the after-pulse
Therefore, it can only work in point-by-point scanning mode, and it often takes several hours to complete a measurement task
[0009] 3) The existing OTDR based on superconducting nanowire single photon detector (SNSPD) has almost no after-pulse effect, which can solve the problem of measurement time. However, SNSPD works near absolute zero, which requires high refrigeration and requires an external Cryogenic liquid helium Dewar bottles or specially designed closed-cycle refrigerators are costly and bulky, and are not suitable for commercial applications
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more
Image
Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
Click on the blue label to locate the original text in one second.
Reading with bidirectional positioning of images and text.
Smart Image
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0048] The optical time domain reflectometer of this embodiment includes a pulsed light source 1, an electronically controlled optical fiber attenuator 2, a circulator 3, an optical fiber to be tested 4, an optical splitter 5, a single photon detector 6, and a first avalanche photodiode (APD) 7, photon counting module 8, main control unit 9, data acquisition module 10, signal amplification module 11; Wherein, single photon detector 6 and photon counting module 8 belong to single photon detection unit, the first avalanche photodiode (APD) 7, The data acquisition module 10 and the signal amplification module 11 belong to common detection units.
[0049] In fact, the optical fiber 4 to be tested is not a part of the optical time domain reflectometer. The probe light enters the optical fiber 4 to be tested after passing through the electronically controlled optical fiber attenuator.
[0050] The single photon detector 6 includes an avalanche photodiode module 61, a high-voltage p...
Embodiment 2
[0098] The difference between this embodiment and the connection relationship of the functional modules in Embodiment 1 is that the common photodetection unit and the single photon detection unit share an avalanche photodiode, and correspondingly, the optical time domain reflectometer of this embodiment does not have an optical splitter , and a control data selector 12 is additionally provided, and the port 931 of the main control unit 9 sends a control command to the data selector 12 .
[0099] The optical time domain reflectometer of this embodiment is such as Figure 5 As shown, it includes a pulse light source 1, an electronically controlled fiber attenuator 2, a circulator 3, an optical fiber to be tested 4, a high voltage power supply module 5, an avalanche photodiode module 6, a gate pulse generator 7, a photon counting module 8, and a main control unit 9 , limiting amplifier 64, pulse discriminator 65, data selector 12 (i.e. data path selection unit), data acquisition ...
Embodiment 3
[0108] The difference between this embodiment and Embodiment 1 is that the optical splitter uses a 99:1 fiber coupler, wherein the optical fiber with a splitting ratio of 99 is connected to the first avalanche photodiode 7, and the splitting ratio is 1. This optical fiber is connected to the single photon detector 6 , and correspondingly, the main control unit 9 is controlled through the port 931 .
[0109] In practical application, it can be realized directly by using a fiber coupler, and its beam splitting ratio can be adjusted according to the application requirements. Usually, the light energy entering the ordinary detection unit is larger than that entering the single photon detection unit.
[0110] Other content of this embodiment can refer to Embodiment 1.
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More
PUM
Login to View More
Abstract
The invention discloses an optical time domain reflectometer and an optical fiber test method. The optical time domain reflectometer comprises a master control unit and a general detection unit. The general detection unit tests returned intensity of backward transmission light when a detection pulse is transmitted in a to-be-tested optical fiber, and feeds back the intensity to the master control unit for event analysis, thereby obtaining a test result. The test result comprises whether there is a fault, and a corresponding fault area. The optical time domain reflectometer also comprises a single photon detection unit. The single photon detection unit is used for testing the intensity of the backward transmission light returned by the fault area when the detection pulse is transmitted in the to-be-tested optical fiber and when the test result comprises the fault, and feeds back the intensity to the master control unit for event analysis, thereby obtaining an accurate location of a fault point. The general detection unit is used for testing optical signal intensity of a non-single photon level. The single photon detection unit is used for testing the optical signal intensity of a single photon level. According to the optical time domain reflectometer and the method, the test speed of a general OTDR is realized, moreover, the test precision of a single photon detection OTDR is realized, combination of rapid scanning and high-precision test is realized, and the structure is simple.
Description
technical field [0001] The invention belongs to the technical field of optical fiber testing, in particular to an optical time domain reflectometer and an optical fiber testing method. Background technique [0002] Optical Time Domain Reflectometer (OTDR) is a sophisticated optoelectronic integrated instrument, which is made of backscattered light produced by Rayleigh scattering and Fresnel reflection when light is transmitted in optical fiber, and is widely used in optical cables During the maintenance and construction of the line, the fiber length, optical transmission loss, joint loss, etc. can be measured, and the fault point can be located. [0003] The avalanche photodiode of an ordinary OTDR works in a linear mode without considering the after-pulse effect. Therefore, it can work in a continuous acquisition state and has the advantage of fast measurement time. However, due to the low gain of the avalanche photodiode working in the linear mode, it cannot detect weak a...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More
Application Information
Patent Timeline
Application Date:The date an application was filed.
Publication Date:The date a patent or application was officially published.
First Publication Date:The earliest publication date of a patent with the same application number.
Issue Date:Publication date of the patent grant document.
PCT Entry Date:The Entry date of PCT National Phase.
Estimated Expiry Date:The statutory expiry date of a patent right according to the Patent Law, and it is the longest term of protection that the patent right can achieve without the termination of the patent right due to other reasons(Term extension factor has been taken into account ).
Invalid Date:Actual expiry date is based on effective date or publication date of legal transaction data of invalid patent.
Login to View More
Patent Type & Authority Patents(China)
IPC IPC(8): H04B10/071H04B10/077
CPCH04B10/071H04B10/0771
Inventor 富尧李浩泉王真真
Owner ZHEJIANG SHENZHOU QUANTUM NETWORK TECH CO LTD
Login to View More 
Login to View More