Fiber-Ring-Based RF Filtering for Temperature and Transversal Loading Measurement and Interrogation

In this paper, we propose and demonstrate a system for simultaneous measurement of temperature and transversal loading based on a fiber-ring microwave photonic filter (MPF). The peak frequencies of the MPF's passbands will shift with temperature of the sensing fiber part and the transversal loading variation will change the fiber micro-bend loss in the ring and thus influence the extinction ratio of the passbands. By monitoring the peak frequency shifts and the extinction ratio of the selected MPF's passbands, simultaneous measurement of temperature and transversal loading can be achieved. The proposed sensing system enjoys high and tailorable sensitivity, good linearity, multiplexing capacity, thus shows a good prospect in practical applications.