Optical Time Domain Reflectometry Fiber Studies

摘要

The wideband frequency capability of optical fibers, the development of very low loss optical fibers (<1 dB/km) and the rapid development of associated optical circuit elements are expected to result in widespread use of optical fiber communication systems in the near future. However, hostile intrusion into these fiber links requires immediate attention and studies, along with a method for detecting these intrusions before hard standards for secure fiber links can be set. The program goal is to develop the OTDR for intrusion monitoring and to establish its ultimate performance limits. An additional objective is to identify and catalog OTDR signatures of different potential intrusions. Large as well as small amplitude microbend in a step-index waveguide can easily be located and measured with the OTDR. A single microbend less than 10 micrometer in amplitude and a periodic microbend approximately 40 periods) of amplitude less than 2 microns were detectable with a computer OTDR test set. (Author)