Crosstalk-free multichannel sensor based on a dual-Sagnac interferometer interrogated by microwave photonic filter

Abstract:

A crosstalk-free multichannel sensor based on a dual-Sagnac interferometer interrogated by microwave photonic filter (MPF) is demonstrated theoretically and experimentally in this paper. The dual-Sagnac interferometer is taken as the sensing element as well as an optical spectrum slicer to implement a dual-passband MPF. Experimental results show that the proposed multichannel sensor is crosstalk-free, and the temperature sensitivity of the each channel is -0.9884 MHz/℃ and -1.9302 MHz/℃, respectively. The sensing interrogation system has good linearity and stability and it is suitable for application scenarios where multiple points of temperature are required to monitor simultaneously.

Key words:multiplexed sensing, microwave photonic filter, comb filtering broadband light source, dual-Sagnac interferometer