Simultanous measurement of temperature and strain based on HiBi FBG using OFDR

This paper presents a new approach of simultaneous measurement of temperature and strain using highly birefringent fiber long Bragg grating (HiBi FBG) based on optical frequency-domain reflectometry (OFDR). This combination enables us to detect two reflected peaks as a function of wavelength and position along the FBG with high spatial resolution. A complex signal processing technique is applied in order to acquire information about temperature and strain change within a single FBG. The simulation results demonstrate temperature and strain distribution along the HiBi FBG, and shift of the central wavelength in the presence of applied temperature and strain change.