公开(公告)号：WO2008116314A1

公开(公告)日：2008-10-02

申请号：PCT/CA2008/000577

申请日：2008-03-28

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC. ,  CYR, Normand ,  CHEN, Hongxin

Inventor： CYR, Normand ,  CHEN, Hongxin

IPC: G01M11/02 ,  H01S3/067 ,  H01S3/082 ,  H01S3/23 ,  H01S5/026 ,  H01S5/10

CPC classification number: G01M11/336 ,  G01M11/335

Abstract: A method and apparatus for measuring at least one polarization-related characteristic of an optical path (FUT) uses a light input unit connected to the FUT at or adjacent a proximal end of the FUT and a light output unit connected to the FUT at or adjacent its proximal or distal end. The light input unit injects into the FUT at least partially polarized light having a controlled state of polarization (I-SOP). The output light unit extracts corresponding light from the FUT, analyzes and detects the extracted light corresponding to at least one transmission axis (A-SOP), and processes the corresponding electrical signal to obtain transmitted coherent optical power at each wavelength of light in each of at least two groups of wavelengths, wherein the lowermost (λ 1 ) and uppermost (λ u ) said wavelengths in each said group of wavelengths are closely- spaced. A processing unit than computes at least one difference in a measured power parameter corresponding to each wavelength in a wavelength pair for each of the at least two groups, the measured power parameter being proportional to the power of the said analyzed and subsequently detected light, thereby defining a set of at least two measured power parameter differences; computes the mean-square value of said set of differences; and calculating the at least one polarization-related FUT characteristic as at least one predetermined function of said mean-square value, the predetermined function being dependent upon the small optical frequency difference between the wavelengths corresponding to the said each at least said two pairs of closely-spaced wavelengths.

Abstract translation: 用于测量光路（FUT）的至少一个偏振相关特性的方法和装置使用在FUT的近端处或邻近FUT连接到FUT的光输入单元，以及连接到FUT在或相邻的FUT的光输出单元 其近端或远端。 光输入单元将具有受控的极化状态（I-SOP）的至少部分偏振光注入到FUT中。 输出光单元从FUT提取对应的光，分析并检测与至少一个透射轴（A-SOP）对应的提取光，并处理相应的电信号，以获得每个波长的每个波长的透射相干光焦度 至少两组波长，其中每个所述波长组中的所述最低（λ1 SUB）和最高（λ

公开(公告)号：WO2007036051A1

公开(公告)日：2007-04-05

申请号：PCT/CA2006/001610

申请日：2006-09-29

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC. ,  CYR, Normand ,  CHEN, Hongxin

Inventor： CYR, Normand ,  CHEN, Hongxin

IPC: G01M11/02 ,  H04B10/08

CPC classification number: G01M11/3181

Abstract: In a method of measuring cumulative polarization mode dispersion (PMD) along the length of a fiber-under-test (FUT), a polarization-sensitive optical time domain reflectometer (POTDR) is used to inject into the FUT plural series of light pulses arranged in several groups. Each group comprises at least two series of light pulses having different but closely-spaced wavelengths and the same state of polarization (SOP). At least two, and preferably a large number of such groups, are injected and corresponding OTDR traces obtained for each series of light pulses by averaging the impulse-response signals of the several series of light pulses in the group. The process is repeated for a large number of groups having didfferent wavelengths and/or SOPs. The PMD then is obtained by normalizing the OTDR traces of all of the groups, then computing the difference between each normalized OTDR trace in one group and the corresponding normalized OTDR trace in another group, followed by the mean-square value of the differences. Finally, the PMD is computed as a predetermined function of the mean-square difference. The function may, for example, be a differential formula, an arcsine formula, and so on.

Abstract translation: 在沿着被测光纤（FUT）的长度测量累积偏振模色散（PMD）的方法中，使用极化敏感光时域反射计（POTDR）将FUT多个系列的光脉冲 在几个组。 每个组包括至少两个具有不同但紧密相隔的波长和相同的偏振状态（SOP）的光脉冲序列。 通过平均组中若干系列的光脉冲的脉冲响应信号，为每一系列光脉冲注入至少两个，优选大量的这样的基团和相应的OTDR迹线。 对于具有正确波长和/或SOP的大量组重复该过程。 然后通过归一化所有组的OTDR迹线获得PMD，然后计算一组中的每个归一化OTDR迹线与另一组中对应的归一化OTDR迹线之间的差异，随后是差的均方值。 最后，将PMD计算为均方差的预定函数。 该函数可以是例如微分公式，反正弦公式等。

公开(公告)号：WO2004070341A1

公开(公告)日：2004-08-19

申请号：PCT/CA2003/000151

申请日：2003-02-06

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC. ,  CYR, Normand

Inventor： CYR, Normand

IPC: G01M11/00

CPC classification number: G01J4/04 ,  G01M11/331 ,  G01M11/336

Abstract: Apparatus for measuring polarization mode dispersion (PMD) of adevice, e. g. a waveguide, comprises a broadband light source (10,12) for passing polarized broadband light through the device (14), an interferometer (20) for dividing and recombining light that has passed through the device to form interferograms, a polarization separator (30) for receiving the light from the interferometer and separating such received light along first and second orthogonalFebruary 25, 2003February 25, 2003 polarization states, detectors (32 x ,32 y ) for converting the first and second orthogonal polarization states, respectively, into corresponding first and second electrical signals (P x (τ),P y (τ)), and a processor (36) for computing the modulus of the difference and such, respectively, of the first and second electrical signals to produce a cross-correlation envelope (E C (τ)) and an auto-correlation envelope (E c (τ)), and determining the polarization mode dispersion according to the expression PMD = where and τ is the delay difference between the paths of the interferometer.

Abstract translation: 用于测量装置的偏振模色散（PMD）的装置， G。 波导，包括用于使偏振宽带光通过装置（14）的宽带光源（10,12），用于分割和重新组合通过该装置的光以形成干涉图的干涉仪（20）;偏振分离器（30） ），用于从所述干涉仪接收光并将所述接收的光沿着第一和第二正交方向分离，2003年2月25日，2003年2月25日，偏振态，用于将第一和第二正交偏振态分别转换成相应的第一和第二相位的检测器（32x，32y） 电信号（Px（τ），Py（tau））和处理器（36），用于分别计算第一和第二电信号的差等的模数，以产生互相关包络（EC（τ ））和自相关包络（Ec（τ）），以及根据表达式PMD =确定偏振模色散，其中τ是干涉仪的路径之间的延迟差 。

公开(公告)号：EP2140243A1

公开(公告)日：2010-01-06

申请号：EP08733675.6

申请日：2008-03-28

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC.

Inventor： CYR, Normand ,  CHEN, Hongxin

IPC: G01M11/02 ,  H01S3/067 ,  H01S3/082 ,  H01S3/23 ,  H01S5/026 ,  H01S5/10

CPC classification number: G01M11/336 ,  G01M11/335

Abstract: A method and apparatus for measuring at least one polarization-related characteristic of an optical path (FUT) uses a light input unit connected to the FUT at or adjacent a proximal end of the FUT and a light output unit connected to the FUT at or adjacent its proximal or distal end. The light input unit injects into the FUT at least partially polarized light having a controlled state of polarization (I-SOP). The output light unit extracts corresponding light from the FUT, analyzes and detects the extracted light corresponding to at least one transmission axis (A-SOP), and processes the corresponding electrical signal to obtain transmitted coherent optical power at each wavelength of light in each of at least two groups of wavelengths, wherein the lowermost (λ1) and uppermost (λu) said wavelengths in each said group of wavelengths are closely- spaced. A processing unit than computes at least one difference in a measured power parameter corresponding to each wavelength in a wavelength pair for each of the at least two groups, the measured power parameter being proportional to the power of the said analyzed and subsequently detected light, thereby defining a set of at least two measured power parameter differences; computes the mean-square value of said set of differences; and calculating the at least one polarization-related FUT characteristic as at least one predetermined function of said mean-square value, the predetermined function being dependent upon the small optical frequency difference between the wavelengths corresponding to the said each at least said two pairs of closely-spaced wavelengths.

公开(公告)号：EP1590646A1

公开(公告)日：2005-11-02

申请号：EP03700784.6

申请日：2003-02-06

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC.

Inventor： CYR, Normand

IPC: G01M11/00

CPC classification number: G01J4/04 ,  G01M11/331 ,  G01M11/336

Abstract: Apparatus for measuring polarization mode dispersion (PMD) of adevice, e. g. a waveguide, comprises a broadband light source (10,12) for passing polarized broadband light through the device (14), an interferometer (20) for dividing and recombining light that has passed through the device to form interferograms, a polarization separator (30) for receiving the light from the interferometer and separating such received light along first and second orthogonalFebruary 25, 2003February 25, 2003 polarization states, detectors (32x,32y) for converting the first and second orthogonal polarization states, respectively, into corresponding first and second electrical signals (Px(τ),Py(τ)), and a processor (36) for computing the modulus of the difference and such, respectively, of the first and second electrical signals to produce a cross-correlation envelope (EC(τ)) and an auto-correlation envelope (Ec(τ)), and determining the polarization mode dispersion according to the expression PMD = where and τ is the delay difference between the paths of the interferometer.

公开(公告)号：EP1590646B1

公开(公告)日：2007-10-24

申请号：EP03700784.6

申请日：2003-02-06

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC.

Inventor： CYR, Normand

IPC: G01M11/00

CPC classification number: G01J4/04 ,  G01M11/331 ,  G01M11/336

Abstract: Apparatus for measuring polarization mode dispersion (PMD) of adevice, e. g. a waveguide, comprises a broadband light source (10,12) for passing polarized broadband light through the device (14), an interferometer (20) for dividing and recombining light that has passed through the device to form interferograms, a polarization separator (30) for receiving the light from the interferometer and separating such received light along first and second orthogonalFebruary 25, 2003February 25, 2003 polarization states, detectors (32x,32y) for converting the first and second orthogonal polarization states, respectively, into corresponding first and second electrical signals (Px(τ),Py(τ)), and a processor (36) for computing the modulus of the difference and such, respectively, of the first and second electrical signals to produce a cross-correlation envelope (EC(τ)) and an auto-correlation envelope (Ec(τ)), and determining the polarization mode dispersion according to the expression PMD = where and τ is the delay difference between the paths of the interferometer.

公开(公告)号：EP1272824B1

公开(公告)日：2004-09-22

申请号：EP01914922.8

申请日：2001-03-30

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC.

Inventor： BABIN, François ,  CYR, Normand

IPC: G01J9/02 ,  G01M11/00

CPC classification number: G01M11/333 ,  G01J9/02 ,  G01M11/338

公开(公告)号：EP1272824A1

公开(公告)日：2003-01-08

申请号：EP01914922.8

申请日：2001-03-30

Applicant: EXFO ELECTRO-OPTICAL ENGINEERING INC.

Inventor： BABIN, François ,  CYR, Normand

IPC: G01J9/02 ,  G01M11/00

CPC classification number: G01M11/333 ,  G01J9/02 ,  G01M11/338

Abstract: In order to avoid errors inherent in the measurement of electrical phase differences or pulse arrival time in relative group delay measurements, different optical signals have their intensity modulated at a common high frequency and different permutations are selected. The amplitudes of corresponding electrical signals are detected and phase differences are computed on the basis of trigonometrical relationships. Because the modulation frequency is known, time differences can be deduced. Apparatus for measuring the phase differences conveniently comprises a slotted wheel which passes selected ones or both of the optical signals. One of the optical signals may be split to produce a third signal with a predetermined phase shift, e.g. about 90 degrees at the modulation frequency and the amplitudes of some possible permutations of the three optical signals used to compute the phase difference. The measurements may be used to compute chromatic dispersion, polarization mode dispersion, elongation, and so on.