WO2012083782A1 - Detection method, device and system of branch optical fiber - Google Patents
Detection method, device and system of branch optical fiber Download PDFInfo
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- WO2012083782A1 WO2012083782A1 PCT/CN2011/083026 CN2011083026W WO2012083782A1 WO 2012083782 A1 WO2012083782 A1 WO 2012083782A1 CN 2011083026 W CN2011083026 W CN 2011083026W WO 2012083782 A1 WO2012083782 A1 WO 2012083782A1
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- 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
- H04B10/071—Arrangements for monitoring or testing transmission systems; Arrangements for fault measurement of transmission systems using a reflected signal, e.g. using optical time domain reflectometers [OTDR]
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/30—Testing of optical devices, constituted by fibre optics or optical waveguides
- G01M11/31—Testing of optical devices, constituted by fibre optics or optical waveguides with a light emitter and a light receiver being disposed at the same side of a fibre or waveguide end-face, e.g. reflectometers
- G01M11/3109—Reflectometers detecting the back-scattered light in the time-domain, e.g. OTDR
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- 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
- H04B10/27—Arrangements for networking
- H04B10/272—Star-type networks or tree-type networks
Definitions
- the invention relates to a method, a device and a system for detecting a branch fiber.
- the application is submitted to the Chinese Patent Office on December 22, 2010, and the application number is 201010600390.
- the invention name is "a method, device and system for detecting a branch fiber" Priority of Chinese Patent Application, the entire contents of which is incorporated herein by reference.
- the present invention relates to the field of communications technologies, and in particular, to a method, device and system for detecting a branch fiber. Background technique
- PON Passive Optical Network
- FTH Fiber To The Home
- the Optical Time Domain Reflectometer is the main means to detect optical path performance and locate optical path failure.
- the OTDR uses a wavelength of 1625 nm / 1650 nm to avoid the operating wavelength of the PON network.
- the OTDR accesses the ODN network on the OLT side through the WDM device.
- the OTDR sends a test optical signal to the optical fiber, and then observes the returned information. This process is repeated, and the results are averaged and displayed in the form of a trajectory that depicts the strength of the signal over the entire length of the fiber, enabling online detection of the fiber link of the PON network.
- the usual PON network structure is: an optical fiber passes from a optical line terminal OLT through a 1: 2 splitter or directly to the building, and then through a The splitter of the large split ratio shifts each branch fiber into each user's home in the building. Large split ratios will cause high losses.
- prior art OTDRs typically use test light pulses that use a frequency bandwidth. However, the use of a wide test light pulse may reduce the resolution of the reflection event, making it impossible for the OTDR to distinguish between dense reflection peaks, which may result in the OTDR not being able to detect the branch fiber after the splitter.
- An object of the present invention is to provide a method, an apparatus, and a system for detecting a branch fiber, which are used to solve the problem of using a frequency bandwidth of a light beam of a splitter fiber for detecting a large split ratio in the prior art.
- the light pulse reduces the resolution of the reflection event of each branch fiber, which causes the 0 TDR to fail to detect the problem of each branch fiber after the beam splitter, thereby realizing the rapid and accurate detection of the branch fiber after the large split ratio splitter, and improving The stability of the passive optical network PON system.
- an embodiment of the present invention provides a method for detecting a branch fiber, where the method includes:
- a test optical signal emitted by the laser is modulated into a first optical signal having a predetermined carrier frequency and transmitted to the optical distribution network; receiving a second optical signal returned from the optical distribution network; converting the second optical signal into a corresponding An electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band-pass filtering; processing the branch fiber according to the electrical signal of the predetermined carrier frequency, and detecting a branch fiber, the device comprising: a laser for providing a test optical signal;
- a modulator for modulating the test optical signal into a first optical signal having a predetermined carrier frequency and transmitting the optical signal to the optical distribution network
- a photoelectric converter configured to receive a second optical signal returned from the optical distribution network, and convert the second optical signal into a corresponding electrical signal
- a band pass filter for performing band pass filtering on the electrical signal converted by the second optical signal to extract an electrical signal having a predetermined carrier frequency
- a processing unit configured to process the branch fiber according to the electrical signal of the predetermined carrier frequency.
- a detection system for a branch fiber comprising:
- a branching fiber detecting device configured to provide a test optical signal; modulating the test optical signal into a first optical signal having a predetermined carrier frequency and transmitting the optical signal to the optical distribution network; and receiving the second optical signal returned by the optical distribution network, Converting the second optical signal into a corresponding electrical signal and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; processing the branched optical fiber according to the electrical signal of the predetermined carrier frequency;
- a wavelength division multiplexing device for uploading, by the detecting device of the branch fiber, a first optical signal having the predetermined carrier frequency to the optical distribution network.
- a method, device and system for detecting a branch fiber provided by the embodiment of the present invention, by modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency and transmitting it to an optical distribution network; receiving the optical distribution from the optical a second optical signal returned by the network; converting the second optical signal into a corresponding electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; according to the electrical signal of the predetermined carrier frequency,
- the branch fiber is processed, It realizes the rapid and accurate detection of each branch fiber of the large split-light ratio splitter, especially the case where the branches of the large split-light splitter are fully matched, which improves the stability of the passive optical network P ON system.
- FIG. 1 is a flowchart of a method for detecting a branch fiber according to an embodiment of the present invention
- FIG. 2 is a schematic structural diagram of a device for detecting a branch fiber according to an embodiment of the present invention
- FIG. 4 is a schematic structural diagram of a detection system of a branch fiber according to an embodiment of the present invention. detailed description
- FIG. 1 is a flowchart of a method for detecting a branch fiber according to an embodiment of the present invention.
- the detection method is specifically performed by the detecting device of the branch fiber, and the detecting device is The optical time domain reflectometer OTDR is described in detail as an example.
- the detecting device is not limited to the OTDR, and any device that detects the optical fiber can be applied.
- Step S102 modulating the test optical signal provided by the laser into a first optical signal having a predetermined carrier frequency and transmitting it to the optical distribution network ODN.
- Optical Time Domain Reflectometer The laser in the OTDR is used to test passive optical networks.
- the branch fiber of the PON reflects the optical signal of the event, and the optical signal is a test optical signal, which is an optical pulse signal.
- the modulator in the 0 TDR modulates the test optical signal into a first optical signal of a predetermined carrier frequency by phase modulation or amplitude modulation, that is, a modulated signal with a predetermined carrier frequency of ⁇ after modulation; modulation of the frequency ⁇
- the signal can be further transmitted by a circulator to a wavelength division multiplexer WDM, which transmits the modulated optical signal to the optical distribution network ODN.
- Step S104 Receive a second optical signal returned from the ODN.
- the second optical signal may be a reflected signal and/or a scatter signal generated by the second optical signal including the first optical signal being reflected and/or scattered by the optical distribution network; for example, in a specific
- the second optical signal may be specifically: the OTDR receives an optical signal returned by each branch fiber from the ODN.
- the returned optical signal includes: a Fresnel reflection signal and a Rayleigh scattering signal.
- Step S106 Convert the second optical signal into a corresponding electrical signal, and extract an electrical signal having the predetermined carrier frequency by band pass filtering.
- the photoelectric converter in the OTDR (for example: avalanche diode APD)
- the optical signal is converted into a corresponding electrical signal for narrowband reception by a bandpass filter. Since the signal returned from the ODN includes a Fresnel reflection signal and a Rayleigh scattering signal, and the Fresnel reflection signal has the same shape as the optical signal sent by the OTDR to the ODN, the Rayleigh scattering signal is the light that the OTDR sends to the ODN.
- the integral of the light intensity of the signal which is independent of the shape of the optical signal sent to the ODN, so when the test optical signal transmitted by the laser is modulated into the first optical signal having the predetermined carrier frequency, it is sent to the optical distribution network,
- the frequency of the Fresnel reflected signal returned by the optical distribution network is a second optical signal of a predetermined carrier frequency, and after photoelectric conversion, passes through a band pass filter (the bandwidth of the band pass filter is a frequency band corresponding to a predetermined carrier frequency) Because of the narrowband filtering, the signal near the predetermined carrier frequency is lifted, that is, the electrical signal corresponding to the Fresnel reflected signal is received, and the electrical signal corresponding to the Rayleigh scattered signal is filtered out.
- the predetermined carrier frequency may be set to be greater than 5 kHz, and the frequency of the general Rayleigh scatter signal is less than or equal to 5 kHz.
- the Rayleigh scattered signal can be filtered out by band pass filtering to ensure the accuracy of the OTDR test.
- the intensity of white noise is related to the bandwidth of the received signal, so reducing the received bandwidth can improve the received signal-to-noise ratio and further improve the accuracy of OTDR detection.
- Step S108 Process the branch fiber according to the electrical signal of the predetermined carrier frequency.
- the OTDR can analyze the Fresnel reflection signal of the predetermined carrier frequency, and accurately detect the branch fiber after the large split ratio. Further, since a large reflection ratio occurs after a dense reflection event, the waveform of the Fresnel reflection signal and the characteristics of the modulation are analyzed according to an electrical signal of a predetermined carrier frequency, that is, a Fresnel reflection signal of a predetermined carrier frequency. It is possible to determine whether the phase or amplitude of the signal reflected by the branch fiber occurs. Change to distinguish the reflection events of each branch, and then determine whether the branch fiber is normal or faulty or broken.
- a method for detecting a branch fiber by modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency and transmitting the signal to an optical distribution network; receiving a return from the optical distribution network a second optical signal; converting the second optical signal into a corresponding electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; performing the branch optical fiber according to the electrical signal of the predetermined carrier frequency
- the processing realizes the rapid and accurate detection of each branch fiber of the large split ratio splitter, especially the case where the branch fibers of the large split ratio splitter are fully matched, and the stability of the passive optical network P ON system is improved.
- An embodiment of the present invention further provides a detecting device for a branch fiber, and a schematic structural view of the detecting device is shown in FIG. 2.
- a branch fiber detecting device includes:
- a laser 200 is provided for providing a test optical signal.
- the laser 200 is specifically configured to generate an optical signal for testing the branch fiber reflection event, where the optical signal is a wider optical pulse signal, and the optical pulse signal band is opposite to the first optical signal of the predetermined carrier frequency.
- the band is wider.
- the modulator 202 is configured to modulate the test optical signal into a first optical signal having a predetermined carrier frequency and transmit the signal to the optical distribution network.
- the modulator 202 is specifically configured to modulate the test optical signal into a first optical signal of a predetermined carrier frequency by phase modulation or amplitude modulation, that is, a modulated signal with a predetermined carrier frequency of ⁇ after modulation; modulation of the frequency ⁇
- the signal may further be transmitted by a circulator 203 to a wavelength division multiplexer WDM, which transmits the modulated first optical signal to an optical distribution network.
- the frequency band corresponding to the first optical signal is narrower than the frequency band corresponding to the test optical signal; the predetermined carrier frequency may be set to be greater than 5K Hz.
- the photoelectric converter 204 is configured to receive a second optical signal returned from the optical distribution network, and convert the second optical signal into a corresponding electrical signal, and send the signal to a band pass filter.
- the photoelectric converter 204 can be an avalanche diode APD.
- the second optical signal may be a reflected signal and/or a scatter signal generated by the second optical signal including the first optical signal being reflected and/or scattered by the optical distribution network; for example, in a specific
- the second optical signal may receive the optical signals returned by the branch fibers from the ODN, including: a Fresnel reflection signal and a Rayleigh scattering signal.
- the band pass filter 206 is configured to perform band-pass filtering on the electrical signal converted by the second optical signal to extract an electrical signal having a predetermined carrier frequency.
- the band pass filter 206 performs narrowband reception. Since the returned signal comprises: a Fresnel reflection signal and a Rayleigh scattering signal, and the Fresnel reflection signal is the same or related to the shape of the optical signal sent to the ODN, the Rayleigh scattering signal is the optical signal sent to the ODN.
- the integral of the light intensity is independent of the shape of the transmitted optical signal, so when the laser transmits to the first optical signal whose test optical signal is modulated to a predetermined carrier frequency, it is sent to the optical distribution network.
- the Fresnel reflected signal returned from the optical distribution network is a second optical signal of a predetermined carrier frequency, and after photoelectric conversion, passes through a band pass filter (the bandwidth of the band pass filter is a frequency band corresponding to a predetermined carrier frequency). Due to the narrowband filtering, the signal near the predetermined carrier frequency is extracted, that is, the electrical signal corresponding to the Fresnel reflected signal is received, and the electrical signal corresponding to the Rayleigh scattered signal is thus filtered out.
- the predetermined carrier can be further set.
- the frequency is greater than 5 kHz, and the frequency of the general Rayleigh scatter signal is less than or equal to 5 kHz.
- the Rayleigh scattered signal can be filtered out by band pass filtering to ensure the accuracy of the OTDR test.
- the intensity of white noise is related to the bandwidth of the received signal, so reducing the received bandwidth can improve the received signal-to-noise ratio and further improve the accuracy of OTDR detection.
- the processing unit 208 is configured to process the branch fiber according to the electrical signal of the predetermined carrier frequency.
- the processing unit may be implemented by a processing circuit, and the processing circuit has the following functions: analyzing a Fresnel reflection signal of the predetermined carrier frequency, and accurately detecting the branched optical fiber after the large split ratio. Further, since a large reflection ratio occurs after a dense reflection event, the waveform of the Fresnel reflection signal and the characteristics of the modulation are analyzed according to an electrical signal of a predetermined carrier frequency, that is, a Fresnel reflection signal of a predetermined carrier frequency. It is possible to determine whether the phase or amplitude of the signal reflected by the branch fiber changes, thereby distinguishing the reflection events of the branches, and further determining whether the branch fiber is normal or faulty or broken.
- the detecting device of the branch fiber may be an optical time domain reflectometer OTDR, but the detecting device is not limited to the OTDR, and any device for detecting the optical fiber may be applied.
- the laser emits a laser pulse signal of lus, which is modulated by a 100MHz sine wave and sent to the ODN through the modulator; the optical signal returned from the ODN is converted into a photocurrent after the APD, and the photocurrent is a 100MHz sine wave signal of a lus
- the output frequency is a sine function centered at 100 MHz, as shown in Fig. 3.
- Fig. 3 is a spectrum diagram of a sine function centered at 100 MHz.
- the 100 MHz photocurrent passes through a band pass filter. Because of the narrow band filtering, only the reflected signal is received, that is, the Fresnel reflected signal with a predetermined carrier frequency of around ⁇ 0 is received, and The Rayleigh scatter signal is therefore filtered out.
- each reflection point on the specific branch fiber can also be judged by the received string of sine waves.
- the reflected waves on the two branched fibers are distinguished by the change in amplitude and phase in the obtained equation.
- the apparatus for detecting a branch fiber provided by the embodiment of the present invention is configured to modulate a test optical signal provided by a laser into an optical signal of a predetermined carrier frequency and transmit the optical signal to the optical distribution network; and receive a second optical signal returned from the optical distribution network. Extracting an electrical signal having the predetermined carrier frequency by using a photoelectric converter and a band pass filter, so that the processing unit performs processing on the branch optical fiber according to the electrical signal of the predetermined carrier frequency, thereby realizing accurate detection of large-spectrum light
- each branch fiber of the splitter especially in the case where the branch fibers of the large split-light splitter are fully matched, the stability of the passive optical network PON system is improved.
- the embodiment of the invention further provides a detection system for a branch fiber, as shown in FIG.
- a branch fiber detection system includes: a branching fiber detecting device 400, wherein the test optical signal provided by the laser is modulated into a first optical signal having a predetermined carrier frequency and sent to the optical distribution network; and the second optical signal returned by the optical distribution network is received, Converting the two optical signals into corresponding electrical signals and extracting electrical signals having the predetermined carrier frequency by band pass filtering; processing the branched optical fibers according to the electrical signals of the predetermined carrier frequencies.
- the wavelength division multiplexing device WDM402 is configured to upload, by the detecting device of the branch fiber, a first optical signal having the predetermined carrier frequency to the optical distribution network.
- the frequency band corresponding to the first optical signal is narrower than the frequency band corresponding to the test optical signal; the second optical signal includes: the first optical signal is reflected and/or scattered in the optical distribution network. The resulting reflected signal and/or scattered signal.
- the second optical signal includes:
- the converting the second optical signal into a corresponding electrical signal and extracting the electrical signal having the predetermined carrier frequency by using a band pass filter specifically includes:
- a frequency of the Fresnel reflected signal is the predetermined carrier frequency
- a frequency band corresponding to the band pass filter is A frequency band corresponding to a predetermined carrier frequency
- the system may also include at least one optical line termination OLT 404, at least one optical network unit ONU 406 and optical distribution network ODN 408.
- the optical distribution network 408 includes a backbone optical fiber 4081.
- the OLT 404 and the optical splitter 4082 are connected by a trunk optical fiber 4081.
- the passive optical splitter 4082 realizes point-to-multipoint optical power distribution and is connected to a plurality of ONUs through a plurality of branch optical fibers 4083.
- the OTDR400 test signal is uploaded to the backbone fiber of the optical distribution network through the WDM 402, and is used to detect the branch optical fiber of each ONU 406 after detecting the optical splitter of the optical splitter in the optical distribution network.
- a detection system for a branch fiber provided by the embodiment of the present invention, by modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency and transmitting the same to an optical distribution network; receiving a return from the optical distribution network a second optical signal; converting the second optical signal into a corresponding electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; performing the branch optical fiber according to the electrical signal of the predetermined carrier frequency
- the processing realizes the rapid and accurate detection of each branch fiber of the large split-light ratio splitter, especially the case where the branches of the large split-light splitter are fully matched, and the stability of the passive optical network PON system is improved.
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Abstract
A detection method of a branch optical fiber is disclosed, comprising modulating a test optical signal provided by a laser device to a first optical signal with a preset carrier frequency, and sending the first optical signal to an optical distribution network; receiving a second optical signal returned from the optical distribution network; converting the second optical signal to a corresponding electric signal, and extracting an electric signal with the preset carrier frequency through bandpass filtering; processing the branch optical fiber according to the electric signal with the preset carrier frequency. Embodiments of the present invention further provide a detection device and system of a branch optical fiber, thereby solving the problem in the prior art that branch optical fibers after a splitter with a great splitting ratio cannot be detected, achieving fast and accurate detection of conditions of each branch optical fiber after the splitter with a great splitting ratio, and improving stability of a passive optical network (PON) system
Description
一种分支光纤的检测方法、 装置和系统 本申请要求于 2010 年 12 月 22 日提交中国专利局、 申请号为 201010600390. 8、 发明名称为 "一种分支光纤的检测方法、 装置和系统" 的中国 专利申请的优先权， 其全部内容通过引用结合在本申请中。 The invention relates to a method, a device and a system for detecting a branch fiber. The application is submitted to the Chinese Patent Office on December 22, 2010, and the application number is 201010600390. 8. The invention name is "a method, device and system for detecting a branch fiber" Priority of Chinese Patent Application, the entire contents of which is incorporated herein by reference.
技术领域 Technical field
本发明涉及通信技术领域， 特别涉及一种分支光纤的检测方法、 装 置和系统。 背景技术 The present invention relates to the field of communications technologies, and in particular, to a method, device and system for detecting a branch fiber. Background technique
随着宽带技术的发展， 无源光网络 （ Passive Optical Network, PON ) 技术是目前应用最广泛的光纤到户 （Fiber To The Home, FTTH ) 技术之 一。 随着 PON网络的使用越来越频繁， 检测 PON网络是否发生故障的技 术也越来越重要。 With the development of broadband technology, Passive Optical Network (PON) technology is one of the most widely used Fiber To The Home (FTTH) technologies. As PON networks become more and more frequently used, techniques for detecting whether a PON network has failed are becoming more and more important.
目前， 光时域反射仪（Optical Time Domain Reflectometer, OTDR)是 检测光路性能和定位光路故障的主要手段。使用 OTDR对 PON网络进行在 线检测时， OTDR使用 1625nm/1650nm的波长， 避开了 PON网络的工作波 长。 OTDR通过波分复用 WDM器件在 OLT侧接入 ODN网络，检测时 , OTDR 对光纤发出一个测试用的光信号， 然后观察返回的信息。 这个过程会重 复地进行， 然后将这些结果进行平均并以轨迹的形式来显示， 这个轨迹 就描绘了在整段光纤内信号的强弱， 从而可以实现在线检测 PON网络的 光纤链路的情况。
在实现本发明的过程中，发明人发现现有技术中至少存在如下问题： 通常的 PON网络结构是： 一根光纤从光线路终端 OLT经过一个 1 : 2 分光器或者直接到大楼， 再通过一个大分光比的分光器， 将各个分支光 纤迁入大楼的各个用户家。 大分光比将造成高损耗， 为提高 OTDR检测的 动态范围，现有技术的 OTDR通常会采用使用频带宽的测试光脉冲。然而， 采用宽的测试光脉冲可能会使反射事件的分辨率降低，使得 OTDR无法分 清楚密集的反射峰，从而导致 OTDR无法检测到分光器后各分支光纤的情 况。 At present, the Optical Time Domain Reflectometer (OTDR) is the main means to detect optical path performance and locate optical path failure. When using OTDR to perform online detection on a PON network, the OTDR uses a wavelength of 1625 nm / 1650 nm to avoid the operating wavelength of the PON network. The OTDR accesses the ODN network on the OLT side through the WDM device. When detecting, the OTDR sends a test optical signal to the optical fiber, and then observes the returned information. This process is repeated, and the results are averaged and displayed in the form of a trajectory that depicts the strength of the signal over the entire length of the fiber, enabling online detection of the fiber link of the PON network. In the process of implementing the present invention, the inventors have found that at least the following problems exist in the prior art: The usual PON network structure is: an optical fiber passes from a optical line terminal OLT through a 1: 2 splitter or directly to the building, and then through a The splitter of the large split ratio shifts each branch fiber into each user's home in the building. Large split ratios will cause high losses. To improve the dynamic range of OTDR detection, prior art OTDRs typically use test light pulses that use a frequency bandwidth. However, the use of a wide test light pulse may reduce the resolution of the reflection event, making it impossible for the OTDR to distinguish between dense reflection peaks, which may result in the OTDR not being able to detect the branch fiber after the splitter.
发明内容 Summary of the invention
本发明实施例的目的是提供一种分支光纤的检测方法、装置和系统 , 用于解决现有技术中为了检测大分光比的分光器后分支光纤的情况而使 用频带宽的光脉冲， 而宽的光脉冲使得各分支光纤的反射事件分辨率降 低，导致 0 T D R无法检测到分光器后各分支光纤的问题，从而实现了快速、 准确检测大分光比分光器后的各分支光纤的情况， 提高了无源光网络 PON系统的稳定性。 An object of the present invention is to provide a method, an apparatus, and a system for detecting a branch fiber, which are used to solve the problem of using a frequency bandwidth of a light beam of a splitter fiber for detecting a large split ratio in the prior art. The light pulse reduces the resolution of the reflection event of each branch fiber, which causes the 0 TDR to fail to detect the problem of each branch fiber after the beam splitter, thereby realizing the rapid and accurate detection of the branch fiber after the large split ratio splitter, and improving The stability of the passive optical network PON system.
为解决上述问题， 本发明实施例提供了一种分支光纤的检测方法， 所 述方法包括： To solve the above problem, an embodiment of the present invention provides a method for detecting a branch fiber, where the method includes:
将激光器发出的测试光信号调制成具有预定载波频率的第一光信号 并发送到光分配网； 接收从所述光分配网返回的第二光信号； 将所述第 二光信号转换成相应的电信号， 并通过带通滤波提取具有所述预定载波 频率的电信号； 根据所述预定载波频率的电信号， 对所述分支光纤进行 处理一种分支光纤的检测装置， 所述装置包括：
激光器， 用于提供测试光信号； A test optical signal emitted by the laser is modulated into a first optical signal having a predetermined carrier frequency and transmitted to the optical distribution network; receiving a second optical signal returned from the optical distribution network; converting the second optical signal into a corresponding An electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band-pass filtering; processing the branch fiber according to the electrical signal of the predetermined carrier frequency, and detecting a branch fiber, the device comprising: a laser for providing a test optical signal;
调制器，用于将所述测试光信号调制成具有预定载波频率的第一光信 号， 并发送到光分配网； a modulator for modulating the test optical signal into a first optical signal having a predetermined carrier frequency and transmitting the optical signal to the optical distribution network;
光电转换器， 用于接收从所述光分配网返回的第二光信号， 并将所述 第二光信号转换成相应的电信号； a photoelectric converter, configured to receive a second optical signal returned from the optical distribution network, and convert the second optical signal into a corresponding electrical signal;
带通滤波器，用于对所述第二光信号转换成的电信号进行带通滤波以 提取出具有预定载波频率的电信号； a band pass filter for performing band pass filtering on the electrical signal converted by the second optical signal to extract an electrical signal having a predetermined carrier frequency;
处理单元， 用于根据所述预定载波频率的电信号， 对所述分支光纤进 行处理。 And a processing unit, configured to process the branch fiber according to the electrical signal of the predetermined carrier frequency.
一种分支光纤的检测系统， 所述系统包括： A detection system for a branch fiber, the system comprising:
分支光纤的检测装置， 用于提供测试光信号； 将所述测试光信号调制 成具有预定载波频率的第一光信号并发送到光分配网； 接收所述光分配 网返回的第二光信号， 将所述第二光信号转换成相应的电信号并通过带 通滤波提取其中具有所述预定载波频率的电信号； 根据所述预定载波频 率的电信号， 对所述分支光纤进行处理； a branching fiber detecting device, configured to provide a test optical signal; modulating the test optical signal into a first optical signal having a predetermined carrier frequency and transmitting the optical signal to the optical distribution network; and receiving the second optical signal returned by the optical distribution network, Converting the second optical signal into a corresponding electrical signal and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; processing the branched optical fiber according to the electrical signal of the predetermined carrier frequency;
波分复用器件，用于将所述分支光纤的检测装置发出的具有所述预定 载波频率的第一光信号上载到所述光分配网。 And a wavelength division multiplexing device for uploading, by the detecting device of the branch fiber, a first optical signal having the predetermined carrier frequency to the optical distribution network.
本发明实施例提供的一种分支光纤的检测方法、 装置和系统， 通过将 激光器提供的测试光信号调制成具有预定载波频率的第一光信号并发送 到光分配网； 接收从所述光分配网返回的第二光信号； 将所述第二光信 号转换成相应的电信号， 并通过带通滤波提取具有所述预定载波频率的 电信号； 根据所述预定载波频率的电信号， 对所述分支光纤进行处理，
实现了快速、 准确检测大分光比分光器的各分支光纤的情况， 尤其是大 分光比分光器的各分支光纤满配的情况， 提高了无源光网络 P ON系统的 稳定性。 附图说明 A method, device and system for detecting a branch fiber provided by the embodiment of the present invention, by modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency and transmitting it to an optical distribution network; receiving the optical distribution from the optical a second optical signal returned by the network; converting the second optical signal into a corresponding electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; according to the electrical signal of the predetermined carrier frequency, The branch fiber is processed, It realizes the rapid and accurate detection of each branch fiber of the large split-light ratio splitter, especially the case where the branches of the large split-light splitter are fully matched, which improves the stability of the passive optical network P ON system. DRAWINGS
为了更清楚地说明本发明实施例的技术方案， 下面将对实施例描述 中所需要使用的附图作简单地介绍。 显而易见地， 下面描述中的附图仅 仅是本发明的一些实施例， 对于本领域普通技术人员来讲， 在不付出创 造性劳动的前提下， 还可以根据这些附图获得其他的附图。 In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings to be used in the description of the embodiments will be briefly described below. Obviously, the drawings in the following description are only some of the embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without paying for labor.
图 1为本发明实施例提供的一种分支光纤的检测方法流程图； 图 2为本发明实施例提供的一种分支光纤的检测装置结构示意图； 图 3为本发明实施例提供的一种以 100MHz为中心的正弦函数 sine的 频谱图； 1 is a flowchart of a method for detecting a branch fiber according to an embodiment of the present invention; FIG. 2 is a schematic structural diagram of a device for detecting a branch fiber according to an embodiment of the present invention; Spectral diagram of a sine function sine centered at 100 MHz;
图 4为本发明实施例提供的一种分支光纤的检测系统结构示意图。 具体实施方式 FIG. 4 is a schematic structural diagram of a detection system of a branch fiber according to an embodiment of the present invention. detailed description
下面将结合本发明实施例中的附图， 对本发明实施例中的技术方案 进行清楚、 完整地描述。 显然， 所描述的实施例仅仅是本发明一部分实 施例， 而不是全部的实施例。 基于本发明中的实施例， 本领域普通技术 人员在没有做出创造性劳动前提下所获得的所有其他实施例， 都属于本 发明保护的范围。 The technical solutions in the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings in the embodiments. It is apparent that the described embodiments are only a part of the embodiments of the invention, rather than all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.
图 1为本发明实施例提供的一种分支光纤的检测方法流程图。 FIG. 1 is a flowchart of a method for detecting a branch fiber according to an embodiment of the present invention.
下面由分支光纤的检测装置具体执行所述的检测方法，以检测装置为
光时域反射计 OTDR为例进行详细说明，所述检测装置并不局限于 OTDR , 任何对光纤进行检测的装置都可以适用。 The detection method is specifically performed by the detecting device of the branch fiber, and the detecting device is The optical time domain reflectometer OTDR is described in detail as an example. The detecting device is not limited to the OTDR, and any device that detects the optical fiber can be applied.
步骤 S 102、将激光器提供的测试光信号调制成具有预定载波频率的第 一光信号并发送到光分配网 ODN。 Step S102, modulating the test optical signal provided by the laser into a first optical signal having a predetermined carrier frequency and transmitting it to the optical distribution network ODN.
具体为： 光时域反射计 OTDR中的激光器发出用于测试无源光网络 Specifically: Optical Time Domain Reflectometer The laser in the OTDR is used to test passive optical networks.
PON的分支光纤反射事件的光信号， 该光信号为测试光信号， 是一种光 脉冲信号。 The branch fiber of the PON reflects the optical signal of the event, and the optical signal is a test optical signal, which is an optical pulse signal.
所述 0 T D R中的调制器通过调相或调幅， 将所述测试光信号调制成预 定载波频率的第一光信号， 即调制后为预定载波频率为 ω的调制信号； 所述频率 ω的调制信号可进一步通过环形器发送到波分复用器 WDM, 所 述 WDM将所述调制后的光信号发送到光分配网 ODN。 The modulator in the 0 TDR modulates the test optical signal into a first optical signal of a predetermined carrier frequency by phase modulation or amplitude modulation, that is, a modulated signal with a predetermined carrier frequency of ω after modulation; modulation of the frequency ω The signal can be further transmitted by a circulator to a wavelength division multiplexer WDM, which transmits the modulated optical signal to the optical distribution network ODN.
其中所述第一光信号所对应的频带比所述测试光信号所对应的频带 窄； 所述预定载波频率可以设置为大于 5K赫兹。 步骤 S104、 接收从所述 ODN返回的第二光信号。 The frequency band corresponding to the first optical signal is narrower than the frequency band corresponding to the test optical signal; and the predetermined carrier frequency may be set to be greater than 5K Hz. Step S104: Receive a second optical signal returned from the ODN.
其中，所述第二光信号可以为所述第二光信号包括所述第一光信号在 所述光分配网发生反射和 /或散射而生成的反射信号和 /或散射信号； 比 如， 在具体实施例中， 所述第二光信号可以具体为： 所述 OTDR从 ODN 接收各分支光纤返回的光信号。 其中所述返回的光信号包括： 菲涅尔反 射 (Fresnel reflection)信号和瑞利散射 (Rayleigh scattering)信号。 The second optical signal may be a reflected signal and/or a scatter signal generated by the second optical signal including the first optical signal being reflected and/or scattered by the optical distribution network; for example, in a specific In an embodiment, the second optical signal may be specifically: the OTDR receives an optical signal returned by each branch fiber from the ODN. The returned optical signal includes: a Fresnel reflection signal and a Rayleigh scattering signal.
步骤 S 106、将所述第二光信号转换成相应的电信号， 并通过带通滤波 提取具有所述预定载波频率的电信号。 Step S106: Convert the second optical signal into a corresponding electrical signal, and extract an electrical signal having the predetermined carrier frequency by band pass filtering.
具体为： 所述 OTDR中的光电转换器 （例如： 雪崩二极管 APD ) 将所
述光信号转换成相应的电信号， 通过带通滤波器进行窄带接收。 由于所 述从 ODN返回的信号包括菲涅尔反射信号和瑞利散射信号， 而菲涅尔反 射信号与 OTDR发送给 ODN的光信号形状相同， 瑞利散射信号是所述 OTDR发送给 ODN的光信号的光强的积分， 其与发送给 ODN的光信号的 形状无关， 所以当激光器发送的测试光信号被调制成具有所述预定载波 频率的第一光信号后， 发送给光分配网， 从光分配网返回的菲涅尔反射 信号的频率即为预定载波频率的第二光信号， 经过光电转换后， 通过带 通滤波器 （该带通滤波器的带宽为预定载波频率对应的频带） 后， 由于 是窄带滤波， 提起预定载波频率附近的信号， 即菲涅尔反射信号相对应 的电信号才会被接收到， 而瑞利散射信号对应的电信号也因此被过滤掉。 为了保证该 0 T D R测试的准确性，进一步可以设置该预定载波频率为大于 5KHZ , 一般瑞利散射信号的频率为小于或者等于 5KHZ。 这样， 通过带 通滤波就可以滤除瑞利散射的信号， 从而保证所述 OTDR测试的准确性。 另外， 白噪声的强度和接收信号的带宽相关， 所以减小接收的带宽， 就 可以提高接收的信噪比， 进一步提高了 OTDR检测的准确性。 Specifically: the photoelectric converter in the OTDR (for example: avalanche diode APD) The optical signal is converted into a corresponding electrical signal for narrowband reception by a bandpass filter. Since the signal returned from the ODN includes a Fresnel reflection signal and a Rayleigh scattering signal, and the Fresnel reflection signal has the same shape as the optical signal sent by the OTDR to the ODN, the Rayleigh scattering signal is the light that the OTDR sends to the ODN. The integral of the light intensity of the signal, which is independent of the shape of the optical signal sent to the ODN, so when the test optical signal transmitted by the laser is modulated into the first optical signal having the predetermined carrier frequency, it is sent to the optical distribution network, The frequency of the Fresnel reflected signal returned by the optical distribution network is a second optical signal of a predetermined carrier frequency, and after photoelectric conversion, passes through a band pass filter (the bandwidth of the band pass filter is a frequency band corresponding to a predetermined carrier frequency) Because of the narrowband filtering, the signal near the predetermined carrier frequency is lifted, that is, the electrical signal corresponding to the Fresnel reflected signal is received, and the electrical signal corresponding to the Rayleigh scattered signal is filtered out. In order to ensure the accuracy of the 0 TDR test, the predetermined carrier frequency may be set to be greater than 5 kHz, and the frequency of the general Rayleigh scatter signal is less than or equal to 5 kHz. In this way, the Rayleigh scattered signal can be filtered out by band pass filtering to ensure the accuracy of the OTDR test. In addition, the intensity of white noise is related to the bandwidth of the received signal, so reducing the received bandwidth can improve the received signal-to-noise ratio and further improve the accuracy of OTDR detection.
步骤 S 108、根据所述预定载波频率的电信号，对所述分支光纤进行处 理。 Step S108: Process the branch fiber according to the electrical signal of the predetermined carrier frequency.
具体为： 所述 OTDR可以分析所述预定载波频率的菲涅尔反射信号 , 对所述大分光比后的分支光纤进行准确检测。 进一步， 由于大分光比后 会出现密集的反射事件， 所以根据预定载波频率的电信号， 即预定载波 频率的菲涅尔反射信号， 分析所述菲涅尔反射信号的波形， 以及调制的 特性， 就能够判断出该分支光纤反射回来的信号的相位或幅度是否发生
改变， 从而来区分各分支的反射事件， 进而判断该分支光纤是正常还是 故障或者断纤等情况。 Specifically, the OTDR can analyze the Fresnel reflection signal of the predetermined carrier frequency, and accurately detect the branch fiber after the large split ratio. Further, since a large reflection ratio occurs after a dense reflection event, the waveform of the Fresnel reflection signal and the characteristics of the modulation are analyzed according to an electrical signal of a predetermined carrier frequency, that is, a Fresnel reflection signal of a predetermined carrier frequency. It is possible to determine whether the phase or amplitude of the signal reflected by the branch fiber occurs. Change to distinguish the reflection events of each branch, and then determine whether the branch fiber is normal or faulty or broken.
本发明实施例提供的一种分支光纤的检测方法，通过将激光器提供的 测试光信号调制成具有预定载波频率的第一光信号并发送到光分配网； 接收从所述光分配网返回的第二光信号； 将所述第二光信号转换成相应 的电信号， 并通过带通滤波提取具有所述预定载波频率的电信号； 根据 所述预定载波频率的电信号， 对所述分支光纤进行处理， 实现了快速、 准确检测大分光比分光器的各分支光纤的情况， 尤其是大分光比分光器 的各分支光纤满配的情况， 提高了无源光网络 P ON系统的稳定性。 A method for detecting a branch fiber according to an embodiment of the present invention, by modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency and transmitting the signal to an optical distribution network; receiving a return from the optical distribution network a second optical signal; converting the second optical signal into a corresponding electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; performing the branch optical fiber according to the electrical signal of the predetermined carrier frequency The processing realizes the rapid and accurate detection of each branch fiber of the large split ratio splitter, especially the case where the branch fibers of the large split ratio splitter are fully matched, and the stability of the passive optical network P ON system is improved.
本发明实施例还提供一种分支光纤的检测装置， 所述检测装置的结 构示意图如图 2所示。 An embodiment of the present invention further provides a detecting device for a branch fiber, and a schematic structural view of the detecting device is shown in FIG. 2.
一种分支光纤的检测装置包括： A branch fiber detecting device includes:
激光器 200, 用于提供测试光信号。 A laser 200 is provided for providing a test optical signal.
所述激光器 200具体用于生成测试所述分支光纤反射事件的光信号， 该光信号为一种较宽的光脉冲信号， 该光脉冲信号频带相对调制后的预 定载波频率的第一光信号而言其频带较宽。 The laser 200 is specifically configured to generate an optical signal for testing the branch fiber reflection event, where the optical signal is a wider optical pulse signal, and the optical pulse signal band is opposite to the first optical signal of the predetermined carrier frequency. The band is wider.
所述调制器 202, 用于所述测试光信号调制成具有预定载波频率的第 一光信号， 并发送到光分配网。 The modulator 202 is configured to modulate the test optical signal into a first optical signal having a predetermined carrier frequency and transmit the signal to the optical distribution network.
所述调制器 202具体用于通过调相或调幅， 将所述测试光信号调制成 预定载波频率的第一光信号， 即调制后为预定载波频率为 ω的调制信号； 所述频率 ω的调制信号进一步可以通过环形器 203发送到波分复用器 WDM , 所述 WDM将所述调制后的所述第一光信号发送到光分配网。
其中所述第一光信号所对应的频带比所述测试光信号所对应的频带 窄； 所述预定载波频率可以设置为大于 5K赫兹。 The modulator 202 is specifically configured to modulate the test optical signal into a first optical signal of a predetermined carrier frequency by phase modulation or amplitude modulation, that is, a modulated signal with a predetermined carrier frequency of ω after modulation; modulation of the frequency ω The signal may further be transmitted by a circulator 203 to a wavelength division multiplexer WDM, which transmits the modulated first optical signal to an optical distribution network. The frequency band corresponding to the first optical signal is narrower than the frequency band corresponding to the test optical signal; the predetermined carrier frequency may be set to be greater than 5K Hz.
光电转换器 204, 用于接收从所述光分配网返回的第二光信号， 并将 所述第二光信号转换成相应的电信号， 发送给带通滤波器。 The photoelectric converter 204 is configured to receive a second optical signal returned from the optical distribution network, and convert the second optical signal into a corresponding electrical signal, and send the signal to a band pass filter.
所述光电转换器 204可以为雪崩二级管 APD。 The photoelectric converter 204 can be an avalanche diode APD.
其中，所述第二光信号可以为所述第二光信号包括所述第一光信号在 所述光分配网发生反射和 /或散射而生成的反射信号和 /或散射信号； 比 如， 在具体实施例中， 所述第二光信号可以从 ODN接收各分支光纤返回 的光信号包括：菲涅尔反射（ Fresnel reflection )信号和瑞利散射（ Rayleigh scattering ) 信号。 The second optical signal may be a reflected signal and/or a scatter signal generated by the second optical signal including the first optical signal being reflected and/or scattered by the optical distribution network; for example, in a specific In an embodiment, the second optical signal may receive the optical signals returned by the branch fibers from the ODN, including: a Fresnel reflection signal and a Rayleigh scattering signal.
所述带通滤波器 206, 用于对所述第二光信号转换成的电信号进行带 通滤波以提取出具有预定载波频率的电信号。 The band pass filter 206 is configured to perform band-pass filtering on the electrical signal converted by the second optical signal to extract an electrical signal having a predetermined carrier frequency.
所述带通滤波器 206进行窄带接收。 由于所述返回的信号包括： 菲涅 尔反射信号和瑞利散射信号， 而菲涅尔反射信号与发送给 ODN的光信号 形状相同或者相关， 瑞利散射信号是所述发送给 ODN的光信号的光强的 积分， 其与发送的光信号的形状无关， 所以当激光器发送给测试光信号 被调制成预定载波频率的第一光信号后， 发送给光分配网。 从光分配网 返回的菲涅尔反射信号即为预定载波频率的第二光信号， 经过光电转换 后， 通过带通滤波器（该带通滤波器的带宽为预定载波频率对应的频带） 后， 由于是窄带滤波， 提取预定载波频率附近的信号， 即菲涅尔反射信 号相对应的电信号才会被接收到， 而瑞利散射信号对应的电信号也因此 被过滤掉。 为了保证该 OTDR测试的准确性， 进一步可以设置该预定载波
频率为大于 5KHZ, —般瑞利散射信号的频率为小于或者等于 5KHZ。 这 样， 通过带通滤波就可以滤除瑞利散射的信号， 从而保证所述 OTDR测试 的准确性。 另外， 白噪声的强度和接收信号的带宽相关， 所以减小接收 的带宽， 就可以提高接收的信噪比， 进一步提高了 OTDR检测的准确性。 The band pass filter 206 performs narrowband reception. Since the returned signal comprises: a Fresnel reflection signal and a Rayleigh scattering signal, and the Fresnel reflection signal is the same or related to the shape of the optical signal sent to the ODN, the Rayleigh scattering signal is the optical signal sent to the ODN The integral of the light intensity is independent of the shape of the transmitted optical signal, so when the laser transmits to the first optical signal whose test optical signal is modulated to a predetermined carrier frequency, it is sent to the optical distribution network. The Fresnel reflected signal returned from the optical distribution network is a second optical signal of a predetermined carrier frequency, and after photoelectric conversion, passes through a band pass filter (the bandwidth of the band pass filter is a frequency band corresponding to a predetermined carrier frequency). Due to the narrowband filtering, the signal near the predetermined carrier frequency is extracted, that is, the electrical signal corresponding to the Fresnel reflected signal is received, and the electrical signal corresponding to the Rayleigh scattered signal is thus filtered out. In order to ensure the accuracy of the OTDR test, the predetermined carrier can be further set. The frequency is greater than 5 kHz, and the frequency of the general Rayleigh scatter signal is less than or equal to 5 kHz. In this way, the Rayleigh scattered signal can be filtered out by band pass filtering to ensure the accuracy of the OTDR test. In addition, the intensity of white noise is related to the bandwidth of the received signal, so reducing the received bandwidth can improve the received signal-to-noise ratio and further improve the accuracy of OTDR detection.
处理单元 208 , 用于根据所述预定载波频率的电信号， 对所述分支光 纤进行处理。 The processing unit 208 is configured to process the branch fiber according to the electrical signal of the predetermined carrier frequency.
具体所述处理单元可以通过处理电路实现， 该处理电路的功能如下： 分析所述预定载波频率的菲涅尔反射信号， 对所述大分光比后的分支光 纤进行准确检测。 进一步， 由于大分光比后会出现密集的反射事件， 所 以根据预定载波频率的电信号， 即预定载波频率的菲涅尔反射信号， 分 析所述菲涅尔反射信号的波形， 以及调制的特性， 就能够判断出该分支 光纤反射回来的信号的相位或幅度是否发生改变， 从而来区分各分支的 反射事件， 进而判断该分支光纤是正常还是故障或者断纤等情况。 Specifically, the processing unit may be implemented by a processing circuit, and the processing circuit has the following functions: analyzing a Fresnel reflection signal of the predetermined carrier frequency, and accurately detecting the branched optical fiber after the large split ratio. Further, since a large reflection ratio occurs after a dense reflection event, the waveform of the Fresnel reflection signal and the characteristics of the modulation are analyzed according to an electrical signal of a predetermined carrier frequency, that is, a Fresnel reflection signal of a predetermined carrier frequency. It is possible to determine whether the phase or amplitude of the signal reflected by the branch fiber changes, thereby distinguishing the reflection events of the branches, and further determining whether the branch fiber is normal or faulty or broken.
上述分支光纤的检测装置可以为光时域反射计 OTDR, 但所述检测装 置并不局限于 OTDR, 任何对光纤进行检测的装置都可以适用 The detecting device of the branch fiber may be an optical time domain reflectometer OTDR, but the detecting device is not limited to the OTDR, and any device for detecting the optical fiber may be applied.
下面举例说明 0 T D R检测大分光比分光器后的分支光纤的过程。 The following is an example of the process in which the 0 T D R detects the branch fiber after the large split ratio splitter.
激光器发出 lus的激光脉冲信号， 通过调制器， 被 100MHz的正弦波调 制后发送到 ODN; 从 ODN返回的光信号， 经过 APD后， 转换成光电流， 该光电流为一段 lus的 100MHz正弦波信号， 通过傅立叶变换， 输出频语 为以 100MHz为中心的 sine函数，如图 3所示，图 3为以 100MHz为中心的 sine 函数的频谱图。 The laser emits a laser pulse signal of lus, which is modulated by a 100MHz sine wave and sent to the ODN through the modulator; the optical signal returned from the ODN is converted into a photocurrent after the APD, and the photocurrent is a 100MHz sine wave signal of a lus Through the Fourier transform, the output frequency is a sine function centered at 100 MHz, as shown in Fig. 3. Fig. 3 is a spectrum diagram of a sine function centered at 100 MHz.
其中， 图中 ω 0=100ΜΗζ, 对于 lus的脉冲， 第一个零点在 100MHz士
1MHz处， 通过 100MHz为中心的 10MHz带宽的带通滤波器， 能量损失艮 小。 Where ω 0=100ΜΗζ, for the pulse of lus, the first zero is at 100MHz At 1MHz, the energy loss is reduced by a bandpass filter with a 10MHz bandwidth centered at 100MHz.
所述 100MHz的光电流通过带通滤波器， 由于是窄带滤波， 所述只有 反射信号才会被接收到， 即接收预定载波频率为 ω 0附近的菲涅尔反射信 号才会被接收到， 而瑞利散射信号也因此被过滤掉。 The 100 MHz photocurrent passes through a band pass filter. Because of the narrow band filtering, only the reflected signal is received, that is, the Fresnel reflected signal with a predetermined carrier frequency of around ω 0 is received, and The Rayleigh scatter signal is therefore filtered out.
进一步的，还可以通过接收到的一串正弦波来判断具体分支光纤上各 反射点的位置。 Further, the position of each reflection point on the specific branch fiber can also be judged by the received string of sine waves.
更进一步的， 若接收两个反射波为重叠的两个反射波， 还可以利用三 角公式来区分： Furthermore, if two reflected waves are received as two reflected waves, they can also be distinguished by a three-corner formula:
由三角公式： sin(a)+sin(b)=2sin((a+b)/2)cos((a-b)/2) From the trigonometric formula: sin(a)+sin(b)=2sin((a+b)/2)cos((a-b)/2)
得到： sin(xt)+sin(xt+a)=2cos(a/2)sin(xt+a/2) Get: sin(xt)+sin(xt+a)=2cos(a/2)sin(xt+a/2)
通过获得的公式中的幅度和相位的改变，从而区别出这两个分支光纤 上的反射波。 The reflected waves on the two branched fibers are distinguished by the change in amplitude and phase in the obtained equation.
本发明实施例提供的一种分支光纤的检测装置， 通过将激光器提供 的测试光信号调制成预定载波频率的光信号并发送到光分配网； 接收从 所述光分配网返回的第二光信号， 通过光电转换器以及带通滤波器， 提 取具有所述预定载波频率的电信号， 使得处理单元根据所述预定载波频 率的电信号， 实现对所述分支光纤进行处理， 实现了准确检测大分光比 分光器的各分支光纤的情况， 尤其是大分光比分光器的各分支光纤满配 的情况， 提高了无源光网络 PON系统的稳定性。 The apparatus for detecting a branch fiber provided by the embodiment of the present invention is configured to modulate a test optical signal provided by a laser into an optical signal of a predetermined carrier frequency and transmit the optical signal to the optical distribution network; and receive a second optical signal returned from the optical distribution network. Extracting an electrical signal having the predetermined carrier frequency by using a photoelectric converter and a band pass filter, so that the processing unit performs processing on the branch optical fiber according to the electrical signal of the predetermined carrier frequency, thereby realizing accurate detection of large-spectrum light In the case of each branch fiber of the splitter, especially in the case where the branch fibers of the large split-light splitter are fully matched, the stability of the passive optical network PON system is improved.
本发明实施例还提供一种分支光纤的检测系统， 如图 4所示。 The embodiment of the invention further provides a detection system for a branch fiber, as shown in FIG.
一种分支光纤的检测系统包括：
分支光纤的检测装置 400, 用于激光器提供的测试光信号调制成具有 预定载波频率的第一光信号并发送到光分配网； 接收所述光分配网返回 的第二光信号， 将所述第二光信号转换成相应的电信号并通过带通滤波 提取其中具有所述预定载波频率的电信号； 根据所述预定载波频率的电 信号， 对所述分支光纤进行处理。 A branch fiber detection system includes: a branching fiber detecting device 400, wherein the test optical signal provided by the laser is modulated into a first optical signal having a predetermined carrier frequency and sent to the optical distribution network; and the second optical signal returned by the optical distribution network is received, Converting the two optical signals into corresponding electrical signals and extracting electrical signals having the predetermined carrier frequency by band pass filtering; processing the branched optical fibers according to the electrical signals of the predetermined carrier frequencies.
所述波分复用器件 WDM402 ,用于将所述分支光纤的检测装置发出的 具有所述预定载波频率的第一光信号上载到所述光分配网。 The wavelength division multiplexing device WDM402 is configured to upload, by the detecting device of the branch fiber, a first optical signal having the predetermined carrier frequency to the optical distribution network.
其中，所述第一光信号所对应的频带比所述测试光信号所对应的频带 窄； 所述第二光信号包括： 所述第一光信号在所述光分配网发生反射和 / 或散射而生成的反射信号和 /或散射信号。 The frequency band corresponding to the first optical signal is narrower than the frequency band corresponding to the test optical signal; the second optical signal includes: the first optical signal is reflected and/or scattered in the optical distribution network. The resulting reflected signal and/or scattered signal.
所述第二光信号包括： The second optical signal includes:
菲涅尔反射信号和瑞利散射信号； Fresnel reflection signal and Rayleigh scattering signal;
所述将所述第二光信号转换成相应的电信号，并通过带通滤波器提取 具有所述预定载波频率的电信号具体包括： The converting the second optical signal into a corresponding electrical signal and extracting the electrical signal having the predetermined carrier frequency by using a band pass filter specifically includes:
将所述菲涅尔反射信号和瑞利散射信号转换成相应的电信号； 通过带通滤波器对所述电信号进行滤波处理，以滤除所述瑞利散射信 号相对应的电信号并输出所述菲涅尔反射信号相对应的电信号； Converting the Fresnel reflection signal and the Rayleigh scattering signal into corresponding electrical signals; filtering the electrical signal by a band pass filter to filter out electrical signals corresponding to the Rayleigh scattering signal and outputting An electrical signal corresponding to the Fresnel reflected signal;
接收所述带通滤波器输出的所述菲涅尔反射信号相对应的电信号，其 中所述菲涅尔反射信号的频率为所述预定载波频率； 所述带通滤波器对 应的频带为所述预定载波频率对应的频带。 Receiving an electrical signal corresponding to the Fresnel reflected signal output by the band pass filter, wherein a frequency of the Fresnel reflected signal is the predetermined carrier frequency; a frequency band corresponding to the band pass filter is A frequency band corresponding to a predetermined carrier frequency.
所述系统还可以包括至少一个光线路终端 OLT404 , 至少一个光网络 单元 ONU406和光分配网 ODN408。其中，光分配网 408包括主干光纤 4081、
光分路器 4082和分支光纤 4083。 OLT404和光分路器 4082之间通过主干光 纤 4081连接， 所述无源光分路器 4082实现点对多点的光功率分配， 并通 过多个分支光纤 4083连接到多个 ONU。 所述 OTDR400测试信号通过 WDM402上载到光分配网的主干光纤上， 用于检测光分配网中大分光比 的分光器后用于连接各 ONU406的分支光纤的情况。 The system may also include at least one optical line termination OLT 404, at least one optical network unit ONU 406 and optical distribution network ODN 408. The optical distribution network 408 includes a backbone optical fiber 4081. Optical splitter 4082 and branch fiber 4083. The OLT 404 and the optical splitter 4082 are connected by a trunk optical fiber 4081. The passive optical splitter 4082 realizes point-to-multipoint optical power distribution and is connected to a plurality of ONUs through a plurality of branch optical fibers 4083. The OTDR400 test signal is uploaded to the backbone fiber of the optical distribution network through the WDM 402, and is used to detect the branch optical fiber of each ONU 406 after detecting the optical splitter of the optical splitter in the optical distribution network.
本发明实施例提供的一种分支光纤的检测系统， 通过将激光器提供 的测试光信号调制成具有预定载波频率的第一光信号并发送到光分配 网； 接收从所述光分配网返回的第二光信号； 将所述第二光信号转换成 相应的电信号， 并通过带通滤波提取具有所述预定载波频率的电信号； 根据所述预定载波频率的电信号， 对所述分支光纤进行处理， 实现了快 速、 准确检测大分光比分光器的各分支光纤的情况， 尤其是大分光比分 光器的各分支光纤满配的情况， 提高了无源光网络 PON系统的稳定性。 A detection system for a branch fiber provided by the embodiment of the present invention, by modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency and transmitting the same to an optical distribution network; receiving a return from the optical distribution network a second optical signal; converting the second optical signal into a corresponding electrical signal, and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; performing the branch optical fiber according to the electrical signal of the predetermined carrier frequency The processing realizes the rapid and accurate detection of each branch fiber of the large split-light ratio splitter, especially the case where the branches of the large split-light splitter are fully matched, and the stability of the passive optical network PON system is improved.
本领域普通技术人员可以理解： 实现上述方法实施例的全部或部分 步骤可以通过程序指令相关的硬件来完成， 前述的程序可以存储于一计 算机可读取存储介质中， 该程序在执行时， 执行包括上述方法实施例的 步骤； 而前述的存储介质包括： ROM、 RAM, 磁碟或者光盘等各种可以 存储程序代码的介质。 A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.
最后应说明的是： 以上实施例仅用以说明本发明的技术方案， 而非 对其限制； 尽管参照前述实施例对本发明进行了详细的说明， 本领域的 普通技术人员应当理解： 其依然可以对前述各实施例所记载的技术方案 进行修改， 或者对其中部分技术特征进行等同替换； 而这些修改或者替 换， 并不使相应技术方案的本质脱离本发明各实施例技术方案的范围。
It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced; and the modifications or substitutions do not deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1、 一种分支光纤的检测方法， 其特征在于， 所述方法包括： 将激光器提供的测试光信号调制成具有预定载波频率的第一光信号， 并发送到光分配网； A method for detecting a branch fiber, the method comprising: modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency, and transmitting the signal to a optical distribution network;
接收从所述光分配网返回的第二光信号； Receiving a second optical signal returned from the optical distribution network;
将所述第二光信号转换成相应的电信号，并通过带通滤波提取具有所 述预定载波频率的电信号； Converting the second optical signal into a corresponding electrical signal and extracting an electrical signal having the predetermined carrier frequency by band pass filtering;
根据所述预定载波频率的电信号， 对所述分支光纤进行处理。 The branch fiber is processed according to an electrical signal of the predetermined carrier frequency.
2、 根据权利要求 1所述的方法， 其特征在于， 所述第一光信号所对应 的频带比所述测试光信号所对应的频带窄。 2. The method according to claim 1, wherein a frequency band corresponding to the first optical signal is narrower than a frequency band corresponding to the test optical signal.
3、根据权利要求 1所述的方法， 其中所述第二光信号包括所述第一光 信号在所述光分配网发生反射和 /或散射而生成的反射信号和 /或散射信 号。 The method of claim 1 wherein said second optical signal comprises a reflected signal and/or a scatter signal generated by said first optical signal being reflected and/or scattered by said optical distribution network.
4、 根据权利要求 3所述的方法， 其特征在于， 所述第二光信号包括： 菲涅尔反射信号和瑞利散射信号； 4. The method according to claim 3, wherein the second optical signal comprises: a Fresnel reflected signal and a Rayleigh scattering signal;
所述将所述第二光信号转换成相应的电信号，并通过带通滤波提取具 有所述预定载波频率的电信号包括： Converting the second optical signal into a corresponding electrical signal and extracting the electrical signal having the predetermined carrier frequency by band pass filtering comprises:
将所述菲涅尔反射信号和瑞利散射信号转换成相应的电信号； 通过带通滤波对所述电信号进行滤波处理，以滤除所述瑞利散射信号 相对应的电信号并输出所述菲涅尔反射信号相对应的电信号； Converting the Fresnel reflection signal and the Rayleigh scattering signal into corresponding electrical signals; filtering the electrical signal by band pass filtering to filter out electrical signals corresponding to the Rayleigh scattering signal and outputting An electrical signal corresponding to a Fresnel reflected signal;
接收所述菲涅尔反射信号相对应的电信号，其中所述菲涅尔反射信号 的频率为所述预定载波频率。 Receiving an electrical signal corresponding to the Fresnel reflected signal, wherein the Fresnel reflected signal The frequency is the predetermined carrier frequency.
5、 一种分支光纤的检测装置， 其特征在于， 所述检测装置包括： 激光器， 用于提供测试光信号； A detecting device for a branch fiber, wherein the detecting device comprises: a laser for providing a test light signal;
调制器，用于将所述测试光信号调制成具有预定载波频率的第一光信 号， 并发送到光分配网； a modulator for modulating the test optical signal into a first optical signal having a predetermined carrier frequency and transmitting the optical signal to the optical distribution network;
光电转换器， 用于接收从所述光分配网返回的第二光信号， 并将所述 第二光信号转换成相应的电信号； a photoelectric converter, configured to receive a second optical signal returned from the optical distribution network, and convert the second optical signal into a corresponding electrical signal;
带通滤波器，用于对所述第二光信号转换成的电信号进行带通滤波以 提取出具有预定载波频率的电信号； a band pass filter for performing band pass filtering on the electrical signal converted by the second optical signal to extract an electrical signal having a predetermined carrier frequency;
处理单元， 用于根据所述预定载波频率的电信号， 对所述分支光纤进 行处理。 And a processing unit, configured to process the branch fiber according to the electrical signal of the predetermined carrier frequency.
6、 根据权利要求 5所述的检测装置， 其特征在于， 所述检测装置还包 括： The detecting device according to claim 5, wherein the detecting device further comprises:
环行器，用于将所述具有预定载波频率的第一光信号发送到波分复用 器， 并通过波分复用器将所述预定载波频率的第一光信号发送给所述光 分配网； 以及接收从所述光分配网返回的所述第二光信号， 将所述第二 光信号发送给所述光电转换器。 a circulator for transmitting the first optical signal having a predetermined carrier frequency to a wavelength division multiplexer, and transmitting, by the wavelength division multiplexer, the first optical signal of the predetermined carrier frequency to the optical distribution network And receiving the second optical signal returned from the optical distribution network, and transmitting the second optical signal to the photoelectric converter.
7、 根据权利要求 5所述的检测装置， 其特征在于， 所述第一光信号所 对应的频带比所述测试光信号所对应的频带窄。 The detecting device according to claim 5, wherein a frequency band corresponding to the first optical signal is narrower than a frequency band corresponding to the test optical signal.
8、 根据权利要求 5所述的检测装置， 其特征在于， 所述第二光信号包 括： 所述第一光信号在所述光分配网发生反射和 /或散射而生成的反射信 号和 /或散射信号。 The detecting device according to claim 5, wherein the second optical signal comprises: a reflected signal generated by the first optical signal being reflected and/or scattered by the optical distribution network and/or Scattering signal.
9、 根据权利要求 8所述的检测装置， 其特征在于， 所述第二光信号包 括： 9. The detecting device according to claim 8, wherein the second optical signal comprises:
菲涅尔反射信号和瑞利散射信号； Fresnel reflection signal and Rayleigh scattering signal;
所述将所述第二光信号转换成相应的电信号，并通过带通滤波器提取 具有所述预定载波频率的电信号包括： Converting the second optical signal into a corresponding electrical signal and extracting the electrical signal having the predetermined carrier frequency by using a band pass filter includes:
将所述菲涅尔反射信号和瑞利散射信号转换成相应的电信号； 通过带通滤波器对所述电信号进行滤波处理，以滤除所述瑞利散射信 号相对应的电信号并输出所述菲涅尔反射信号相对应的电信号； Converting the Fresnel reflection signal and the Rayleigh scattering signal into corresponding electrical signals; filtering the electrical signal by a band pass filter to filter out electrical signals corresponding to the Rayleigh scattering signal and outputting An electrical signal corresponding to the Fresnel reflected signal;
接收所述带通滤波器输出的所述菲涅尔反射信号相对应的电信号，其 中所述菲涅尔反射信号的频率为所述预定载波频率。 And receiving an electrical signal corresponding to the Fresnel reflected signal output by the band pass filter, wherein a frequency of the Fresnel reflected signal is the predetermined carrier frequency.
10、 根据权利要求 5所述的检测装置， 其特征在于， 所述带通滤波器 对应的频带为所述预定载波频率对应的频带。 The detecting device according to claim 5, wherein the band corresponding to the band pass filter is a band corresponding to the predetermined carrier frequency.
1 1、 一种分支光纤的检测系统， 其特征在于， 所述系统包括： 分支光纤的检测装置，用于将激光器提供的测试光信号调制成具有预 定载波频率的第一光信号并发送到光分配网； 接收所述光分配网返回的 第二光信号， 将所述第二光信号转换成相应的电信号并通过带通滤波提 取其中具有所述预定载波频率的电信号； 根据所述预定载波频率的电信 号， 对所述分支光纤进行处理； 1 . A detection system for a branch fiber, characterized in that: the system comprises: a branch fiber detecting device for modulating a test optical signal provided by a laser into a first optical signal having a predetermined carrier frequency and transmitting the light to the light Receiving a second optical signal returned by the optical distribution network, converting the second optical signal into a corresponding electrical signal and extracting an electrical signal having the predetermined carrier frequency by band pass filtering; An electrical signal of a carrier frequency for processing the branch fiber;
波分复用器件，用于将所述分支光纤的检测装置发出的具有所述预定 载波频率的第一光信号上载到所述光分配网。 And a wavelength division multiplexing device for uploading, by the detecting device of the branch fiber, a first optical signal having the predetermined carrier frequency to the optical distribution network.
12、 根据权利要求 1 1所述的系统， 其特征在于， 所述第二光信号包括 所述第一光信号在所述光分配网发生反射和 /或散射而生成的反射信号和 /或散射信号； 其中所述第一光信号所对应的频带比所述测试光信号所对 应的频带窄。 12. The system according to claim 11, wherein the second optical signal comprises a reflected signal generated by the first optical signal being reflected and/or scattered by the optical distribution network and And a scatter signal; wherein a frequency band corresponding to the first optical signal is narrower than a frequency band corresponding to the test optical signal.
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| CN102136867B (en) * | 2010-12-22 | 2014-03-12 | 华为技术有限公司 | Method, device and system for detecting branch optical fiber |
| CN102523038B (en) * | 2011-12-06 | 2015-04-29 | 华为技术有限公司 | Optical time-domain reflectometer, reflection event detection method and optical network system |
| CN104737472B (en) * | 2013-08-23 | 2017-10-17 | 华为技术有限公司 | Optical-fiber network monitoring device, optical communication system and optical-fiber network monitoring method |
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| CN107431552B (en) | 2015-04-15 | 2019-02-26 | 华为技术有限公司 | Optical module and the network equipment |
| CN104811241A (en) * | 2015-04-29 | 2015-07-29 | 中国科学院半导体研究所 | Wavelength-tunable optical time domain reflectometer and fiber ring-down cavity sensor array integrated system |
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| CN109286441A (en) * | 2018-11-26 | 2019-01-29 | 瑞斯康达科技发展股份有限公司 | A kind of fibre-optic transmission system (FOTS) and the method for information transmission |
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| CN102136867A (en) | 2011-07-27 |
| CN102136867B (en) | 2014-03-12 |
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