Improving fiber optic sensing by all-optical signal processing

We demonstrated the use of optical signal processing to enhance the performance of optical fiber sensors, including FBG sensor and OFDR. Regarding FBG sensors, FWM in a HNLF to enhance the sensitivity of a fiber sensor is demonstrated based on frequency chirp magnification. Meanwhile, OFDR with improved spatial resolution is realized assisted by high power modulation, FWM and RFS. The use of the all-optical signal processing opens a new window for advanced fiber optic sensing. Since the method only processes the signal and thus it can be applied to a wide range of sensors without changing the sensor itself.