光纤链路检测教程.ppt

* * I will start with network FTTH technology. * These are the key factors for deploying FTTH. The increasing demand in voice, data, and video – the so-called Triple Play – is spreading the need for FTTH. This can be seen particularly in video services such as broadcast and premium channels, pay-per-view, video-on-demand, and high definition television. * The PON system can be divided into several types depending on how many splitters are deployed. The top diagram shows a single coupler using one 1 x 32 splitter. The second diagram shows a combination of splitters with 1 x 2 and 1 x 16 configurations. The last diagram shows a combination of splitters with 1 x 4 and 1 x 8 configurations. This is the system that is mainly used in Japan. * I will explain the general GE-PON configuration. On the left is the subscriber premise and on the right is the central office. The wavelength for data transmission to the subscriber is 1490nm, and the data transmission to the central office is 1310nm and the video transmission to the subscriber is 1550nm. The monitoring waveform from the central office to the user is 1625nm or 1650nm. There are one or two splitters in the optical fiber to cover the subscriber premise. The examples in Japan will be explained later. 般的なGE-PONシステムの構成について説明します。 右側が局舎（Central Office）で左側がユーザー宅になります。 通信用波長としては、ユーザーへのデータ送信に1490nm, 局舎へのデータ送信に1310nm、ユーザーへのビデオ送信に1550nmを使用します。また、局舎からユーザー宅への光線路監視（Monitoring）として1625nmもしくは1650nmを使用します。 より多くのユーザー宅をカバーするために、線路の途中に1段ないし2段のSplitterが配置されます。 後ほど日本での事例として詳細に説明します。 * This is an example of optical fiber wiring within a subscriber premise. Up to now, optical fibers could not handle extreme degrees of bending, however, with the development of free bending optical cords, it is easy to wire optical fibers to the user’s homes. * I will start with network FTTH technology. * High resolution OTDR, optical time-domain reflectometer, is used to analyze the failures on the optical fiber lines on the splitters from the