公开(公告)号：US06512610B1

公开(公告)日：2003-01-28

申请号：US09261835

申请日：1999-03-03

申请人： Takao Minami ,  Nobuaki Takeuchi ,  Keiichi Shimizu ,  Koichi Shinozaki ,  Takamu Genji

发明人： Takao Minami ,  Nobuaki Takeuchi ,  Keiichi Shimizu ,  Koichi Shinozaki ,  Takamu Genji

IPC分类号： H04B1008

CPC分类号： G01M11/3136

摘要： A multi-branch optical network testing method (or device) is provided to perform a fault isolation test on an optical network that branches off at a branch point by a number of optical lines having terminal ends respectively. Herein, optical pulses are input to the optical network, from which they are returned as reflection beams. Then, response beams corresponding to mixture of the reflection beams are converted to OTDR waveform data representing a waveform whose optical power gradually decreases in accordance with a distance from an OTDR measurement device and which has a number of reflection peaks. The OTDR waveform data are subjected to logarithmic conversion to produce logarithmic waveform data representing a logarithmic waveform. An approximation method of least squares is effected on the logarithmic waveform data to produce an approximation line, which crosses the logarithmic waveform at points of intersection corresponding to Fresnel reflection points. Using the Fresnel reflection points as split points to split the OTDR waveform data into a number of ranges. Attenuation constants are repeatedly calculated with respect to each of the ranges every measurement time and are stored in a storage device. Thereafter, fault determination is automatically performed based on the attenuation constants stored in the storage device with respect to the fault occurrence time, fault occurrence line and fault occurrence distance.

摘要翻译： 提供了一种多分支光网络测试方法（或设备），用于在分支点分支多个具有终端的光线路的光网络上执行故障隔离测试。 这里，光脉冲被输入到光网络，作为反射光束返回。 然后，对应于反射光束的混合的响应光束被转换为表示根据与OTDR测量装置的距离而光功率逐渐减小的波形的OTDR波形数据，并且具有多个反射峰值。 对OTDR波形数据进行对数转换，生成表示对数波形的对数波形数据。 对对数波形数据进行最小二乘法近似法，得到近似线，该近似线与对应于菲涅尔反射点的交点处的对数波形相交。 使用菲涅尔反射点作为分割点将OTDR波形数据分割成多个范围。 衰减常数相对于每个测量时间的每个范围重复计算并存储在存储装置中。 此后，基于存储在存储装置中的故障发生时间，故障发生线和故障发生距离的衰减常数自动执行故障确定。

公开(公告)号：US06310702B1

公开(公告)日：2001-10-30

申请号：US09099502

申请日：1998-06-18

申请人： Takao Minami ,  Nobuaki Takeuchi ,  Naoyuki Nozaki ,  Koichi Shinozaki ,  Takamu Genji

发明人： Takao Minami ,  Nobuaki Takeuchi ,  Naoyuki Nozaki ,  Koichi Shinozaki ,  Takamu Genji

IPC分类号： H04B1008

CPC分类号： H04B10/272 ,  H04B10/071

摘要： A testing device performs testing on a multistage multi-branch optical network, which contains optical lines (such as optical fibers) that are connected together at connection points (e.g., optical couplers) in a multistage multi-branch manner. An OTDR measurement device uses software to perform fault determination with respect to the multistage multi-branch optical network. Herein, optical pulses are input to an input end of the multistage multi-branch optical network, wherein they are reflected at certain portions of the optical lines and the connection points while propagating through the optical lines. Then, reflected beams are returned to the input end and are mixed together as response light, which is measured by the OTDR measurement device. The response light is converted to a plurality of digital waveform data representing a measured waveform, which is then divided into multiple ranges on the basis of the Fresnel reflection points and connection points. Separative analysis is performed on the digital waveform data belonging to each of the ranges of the measured waveform. The separative analysis is repeated at measuring times, which are determined in advance. So, the fault determination is made by comparing results of the separative analysis, which are obtained at the measuring times respectively. By the fault determination, it is possible to determine a fault line and a fault location (or fault distance) as well as a fault time.

摘要翻译： 测试装置在多级多分支光网络上进行测试，该多网络光网络包含以多级多分支方式在连接点（例如，光耦合器）处连接在一起的光线路（例如光纤）。 OTDR测量装置使用软件对多级多分支光网络执行故障确定。 这里，光脉冲被输入到多级多分支光网络的输入端，其中它们在通过光线路传播的​​同时在光线路和连接点的某些部分被反射。 然后，反射光束返回到输入端，并作为响应光混合在一起，由OTDR测量装置测量。 将响应光转换成表示测量波形的多个数字波形数据，然后根据菲涅耳反射点和连接点将其分成多个范围。 对属于测量波形的每个范围的数字波形数据执行分离分析。 在测量时间重复分离分析，这是预先确定的。 因此，通过比较分别在测量时间分别获得的分析结果进行故障确定。 通过故障确定，可以确定故障线路和故障位置（或故障距离）以及故障时间。

公开(公告)号：US06028661A

公开(公告)日：2000-02-22

申请号：US986733

申请日：1997-12-08

申请人： Takao Minami ,  Nobuaki Takeuchi ,  Naoyuki Nozaki ,  Koichi Shinozaki ,  Takamu Genji

发明人： Takao Minami ,  Nobuaki Takeuchi ,  Naoyuki Nozaki ,  Koichi Shinozaki ,  Takamu Genji

IPC分类号： G01B11/00 ,  G01M11/00 ,  G01N21/00

CPC分类号： G01M11/3136

摘要： A multi-branched optical line testing apparatus can automatically detect a faulty line in multi-branched optical lines and the distance to the fault point. An optical pulse is introduced to the branch point of optical fibers and is reflected inside the respective optical fibers. The waveform of the returning response light is analyzed by an optical time-domain reflectometer (OTDR) measuring apparatus to detect a fault in the respective optical fibers and to determine the fault point. The OTDR measuring apparatus periodically converts the response light which is returned from the respective optical fibers into a digital waveform data group, calculates the attenuation ratios of the respective optical fibers by performing separation analysis of the digital waveform data group, and determines the faulty line and the position of the fault point based on the change of the attenuation ratio of the respective optical fibers.

摘要翻译： 多分支光线路测试装置可以自动检测多分支光线路中的故障线路和故障点的距离。 将光脉冲引入到光纤的分支点，并在各光纤内反射。 通过光时域反射计（OTDR）测量装置分析返回响应光的波形，以检测各光纤中的故障并确定故障点。 OTDR测量装置将从各个光纤返回的响应光周期性地转换为数字波形数据组，通过执行数字波形数据组的分离分析来计算各个光纤的衰减比，并确定故障线 基于相应光纤的衰减比的变化的故障点的位置。