Study on Detecting the Position by an Optical Fiber Sensor with Polarization Fluctuation using the Stokes Parameters

摘要

Recently, demand for an optical fiber sensor system is increasing because of its immunity to electromagnetic interference and lightning strike and its needlessness of power supply along sensing fiber cable. Optical fiber sensors which can specify a position of accident has been also studied. We studied an optical fiber sensor using polarization fluctuation to detect a position of accident. This system is suitable for real time monitoring without high cost systems and complicated composition. We have reported that the error of detecting the position is within ±300m by adjusting the light power of steady state condition to low level. However it is difficult to adjust the light power constantly for a practical optical fiber sensor. Therefore, we have studied the way to specify a position using the Stokes parameters for detecting the variations of polarization from random state. As a result, we could estimate that the error of detecting the position was within ±400 m.