公开(公告)号：US20160142135A1

公开(公告)日：2016-05-19

申请号：US14932375

申请日：2015-11-04

Applicant: EXFO INC.

Inventor： Gang HE ,  Daniel GARIEPY

IPC: H04B10/079

CPC classification number: H04B10/07953

Abstract: There are provided methods and devices for determining a quality parameter characterizing an optical communication signal, the methods being performed by signal detection devices. At the transmitting end, there are obtained a signal power P1 of a first optical signal, a signal power P2 of a second optical signal, a signal power P3 of a third optical signal, optionally a signal power P4 of a fourth optical signal, and a total signal power Ps of a channel where the first, second, third and optional fourth optical signals are located. At a detection point, there are further obtained a signal power P1′ of the first optical signal, a signal power P2′ of the second optical signal, a signal power P3′ of the third optical signal and optionally a signal power P4′ of the fourth optical signal. There are then determined a signal deformation factor SDF and/or an optical signal to ASE noise ratio OSNR from the obtained signal powers.

Abstract translation: 提供了用于确定表征光通信信号的质量参数的方法和装置，所述方法由信号检测装置执行。 在发送端，获得第一光信号的信号功率P1，第二光信号的信号功率P2，第三光信号的信号功率P3，可选地是第四光信号的信号功率P4，以及 第一，第二，第三和任选的第四光信号所在的信道的总信号功率Ps。 在检测点，进一步获得第一光信号的信号功率P1'，第二光信号的信号功率P2'，第三光信号的信号功率P3'以及可选地的第三光信号的信号功率P4' 第四光信号。 然后从获得的信号功率确定信号变形因子SDF和/或光信号对ASE噪声比OSNR。

公开(公告)号：US20160202418A1

公开(公告)日：2016-07-14

申请号：US14301646

申请日：2014-06-11

Applicant: EXFO Inc.

Inventor： Remi FORTIN ,  Gang HE

IPC: G02B6/26 ,  G02B6/028

CPC classification number: G02B6/268 ,  G02B6/0281 ,  G02B6/0288 ,  G02B6/14

Abstract: There is provided a modal distribution conditioner comprising the combination of a mandrel-wrapped optical fiber and an adjustable and fixable loop of optical fiber. It is noted that light entering the modal distribution conditioner is to be generally overfilled compared with the target encircled flux function (as defined by the Standard). The mandrel wrapping introduces macrobends to the optical fiber, inducing modal pre-filtering that roughly transforms the initially overfilled modal distribution to be close to compliance with the appropriate Standard. However, the modal distribution of light having traversed the fixed mandrel typically remains somewhat overfilled. The adjustable loop provides for the fine-tuning of the modal distribution, in conformity with the Standard. Once the requirements defined by the Standard are met, the adjustable loop may be secured in place such that modal distribution becomes fixed and remain stable.

Abstract translation: 提供了一种模式分配调节器，其包括芯棒包裹的光纤和可调节和可固定的光纤环路的组合。 注意到，与目标环绕通量函数（如标准所定义）相比，进入模态分布调节器的光通常被过度填充。 心轴缠绕将宏弯引入光纤，诱导模态预过滤，粗略地将初始过度填充的模态分布转化为接近于符合相应标准。 然而，穿过固定心轴的光的模态分布通常保持有些过度填充。 可调节环路根据标准对模态分布进行微调。 一旦满足标准规定的要求，可调节环路可以固定就位，使得模态分布变得固定并保持稳定。

公开(公告)号：US20240283532A1

公开(公告)日：2024-08-22

申请号：US18392359

申请日：2023-12-21

Applicant: EXFO Inc.

Inventor： Gang HE ,  Gwennael AMICE

IPC: H04B10/077 ,  H04B10/079

CPC classification number: H04B10/0775 ,  H04B10/0795

Abstract: There are herein provided methods and systems to characterize optical propagation characteristics of an optical fiber communication link (such as, e.g., a submarine line system), including ASE noise (such as traditional OSNRASE), non-linear noise (such as OSNRNL due to nonlinear distortions) and/or the GOSNR. The method uses a polarized probe signal in the optical transmission channel under test in order to probe the link under test, as well as power loading light in other optical transmission channels in order to activate non-linear effects. The propagated test signal is then analyzed under varied polarization conditions using a varied-SOP polarization-resolved optical spectrum analysis of the propagated probe signal.

公开(公告)号：US20240283531A1

公开(公告)日：2024-08-22

申请号：US18416224

申请日：2024-01-18

Applicant: EXFO INC.

Inventor： Gang HE

IPC: H04B10/073 ,  H04B10/293

CPC classification number: H04B10/0731 ,  H04B10/293

Abstract: Methods and systems are disclosed for characterizing a polarization-dependent loss or gain (PDL/G) of an optical device under test (DUT), such as an optical fiber link, from an optical signal having passed through the optical DUT. The optical signal is substantially unpolarized upon entering the optical DUT. The method can include varying a state of polarization (SOP) of the optical signal over a plurality of sampled SOP conditions to produce a respective plurality of SOP-varied optical signals; performing a polarization-analysis and detection operation on the plurality of SOP-varied optical signals to acquire a respective plurality of detected signal sets, each detected signal set including at least one polarization-analyzed detected signal; and determining, as the PDL/G of the optical DUT, a polarization extinction ratio parameter representative of a ratio of maximum to minimum power levels measured among the polarization-analyzed detected signals of the plurality of detected signal sets.

公开(公告)号：US20210273722A1

公开(公告)日：2021-09-02

申请号：US17183415

申请日：2021-02-24

Applicant: EXFO Inc.

Inventor： Gang HE ,  Daniel GARIEPY

IPC: H04B10/079 ,  H04B10/073

Abstract: There is herein provided a method for measuring the GOSNR that can be implemented using commercial-grade transceivers and which accounts for linear optical impairments (e.g. PMD, PDL and CD) and transceiver intrinsic impairments. The method may be implemented using an Optical Spectrum Analyzer (OSA) and either the system transceivers or other commercial-grade transceivers. The proposed measurement method is based on mixed optical and electronic technologies, using an OSA and a transceiver pair. By measuring a signal quality metric Qm and the OSNR under varied power and ASE noise conditions, a constant value RBW that relates the GOSNR to the signal quality metric Qm is derived. The GOSNR is then obtained from these results.

公开(公告)号：US20140328586A1

公开(公告)日：2014-11-06

申请号：US14268144

申请日：2014-05-02

Applicant: EXFO Inc.

Inventor： Gang HE ,  Daniel GARIEPY ,  Mats SKOLD

IPC: H04B10/079 ,  H04J14/06

CPC classification number: H04B10/07953 ,  H04J14/06

Abstract: There is provided a method and an apparatus for determining quality parameters on a polarization-multiplexed optical signal based on an analysis of the power spectral density of the Signal-Under-Test (SUT). The method is predicated upon knowledge of the spectral shape of the signal in the absence of significant noise or spectral deformation. This knowledge is provided by a reference optical spectrum trace. Based on this knowledge and under the assumption that ASE noise level is approximately constant in wavelength over a given spectral range, the spectral deformation of the signal contribution of the SUT may be estimated using a comparison of the spectral variations of the optical spectrum trace of the SUT with that of the reference optical spectrum trace.

Abstract translation: 提供了一种基于对测试信号（SUT）的功率谱密度的分析来确定偏振复用光信号质量参数的方法和装置。 该方法基于在没有显着噪声或光谱变形的情况下对信号的光谱形状的了解。 该知识由参考光谱轨迹提供。 基于这一知识，并假设ASE噪声水平在给定光谱范围内的波长近似恒定，则SUT的信号贡献的光谱变形可以使用光谱轨迹的光谱变化的比较来估计 SUT与参考光谱图谱相同。

公开(公告)号：US20200249121A1

公开(公告)日：2020-08-06

申请号：US16776692

申请日：2020-01-30

Applicant: EXFO Inc.

Inventor： Gang HE

IPC: G01M11/00

Abstract: There is provided an optical loss testing system for multi-fiber array cables an optical loss test method and a reference method therefor which overcomes at least part of the multi-powermeter uncertainty. A prior calibration step serves to characterize the relative difference in optical power response of the multiple power meters. This relative difference can then be used to correct the optical loss measurement so as to eliminate its effect.

公开(公告)号：US20220038177A1

公开(公告)日：2022-02-03

申请号：US17443607

申请日：2021-07-27

Applicant: EXFO Inc.

Inventor： Gang HE ,  Michel LECLERC

IPC: H04B10/079 ,  G02B6/42

Abstract: There are provided herein test instruments, devices and methods for measuring the optical power loss of optical-fiber devices under test, and particularly those terminated with multifiber connectors, which allows for a one-cord or one-cord equivalent reference method whichever the pinning of the actual optical-fiber device under test. There is proposed to add an optical-fiber expansion device to convert the pinning of the input interface of the power meter instrument from pinned to unpinned or vice-versa, while not adding extra measurement uncertainty. This is accomplished using a patch cord which core diameter is between that of the device under test and that of the input interface of the power meter instrument.

公开(公告)号：US20190305845A1

公开(公告)日：2019-10-03

申请号：US16445992

申请日：2019-06-19

Applicant: EXFO Inc.

Inventor： Normand CYR ,  Gang HE ,  Bernard RUCHET

IPC: H04B10/079

Abstract: Method and systems for characterizing an optical signal propagating along a communication link are disclosed. The signal includes a data-carrying signal contribution, modulated at a symbol frequency, and a noise contribution. The method includes measuring an optical power spectrum of the signal, which includes a data-carrying signal spectrum component and a noise spectrum component. The method also includes determining a measured spectral correlation function within pairs of spectral components of the signal as a function of center frequency of the pairs, the spectral components in each pair being spectrally separated from each other by the symbol frequency. The method further includes obtaining a solution for the data-carrying signal spectrum component based on the measured optical power spectrum, such that a calculated spectral correlation function based on the solution matches the measured spectral correlation function. In some embodiments, the spectral correlation function is measured as a low-frequency beatnote amplitude function.

公开(公告)号：US20160127074A1

公开(公告)日：2016-05-05

申请号：US14931983

申请日：2015-11-04

Applicant: EXFO INC.

Inventor： Gang HE ,  Daniel GARIEPY

IPC: H04J14/06 ,  H04B10/079

CPC classification number: H04J14/06 ,  H04B10/0775 ,  H04B10/07953

Abstract: There is provided a method to discriminate NLE-induced signal deformation from ASE-noise on polarization multiplexed signals, in order to measure the OSNR under NLE conditions and/or characterize the NLE-induced signal deformation. In accordance with one aspect, the method is based on the acquisition of optical spectrum traces when the (data-carrying) optical communication signal is partially or completely extinguished (ASE-noise only), as well as with a live optical communication signal. Comparing traces acquired with different conditions and/or at different dates allows discrimination of the signal contribution, the ASE-noise contribution and the NLE-induced deformations on the SUT.

Abstract translation: 提供了一种在偏振复用信号上区分NLE诱发的信号变形与ASE噪声的方法，以便在NLE条件下测量OSNR和/或表征NLE引起的信号变形。 根据一个方面，该方法基于当（数据携带）光通信信号被部分或完全熄灭（仅限于ASE噪声）以及带有实时光通信信号时获取光谱踪迹。 比较采用不同条件和/或不同日期的踪迹可以区分信号贡献，ASE噪声贡献和NLE引起的SUT变形。