[21a-211B-1~9] 4.2 Photonics Devices, Photonic Integrated Circuit and Silicon Phonics

▲ [21a-211B-8] FBG Interrogation using SMS fiber and OTDR for Simultaneous Measurements of Temperature and Strain

〇(D)KOUSTAV dey DEY¹, Sourabh Roy¹, Sai Shankar M¹, Ramesh Kumar B², Kishore P¹ (1.NIT Warangal, 2.IPR Gandhinagar)

Keywords:optical fiber, FBG, Interrogation

A simple and efficient method of interrogating Fiber Bragg Grating (FBG) sensor signals is proposed here using Single mode-Multimode-Single mode (SMS) fiber device and Optical Time Domain Reflectometer (OTDR). Eventually the sensor signals are analyzed for dual parameter measurement of temperature and strain. The SMS fiber device explored the multimode interference (MMI) which occurs along the length of multimode fiber (MMF) . The power loss is measured with variation of temperature and strain separately and also for the variation of temperature at discreet constant load (100 to 500 gms with an increment of 100 gms) in the range of 25⁰C to 100⁰C. As the FBG peak follows the linear slope region of SMS, it is expected that the response of OTDR also to be linear which is confirmed from the obtained results, that showing good linearity with adjustable R² =0.98. Our scheme of interrogation is expected to be robust, cheap and more efficient for simultaneous measurement of temperature and strain with good sensitivity.