The Scheme Design and Accuracy Analysis of Coherent Self-Heterodyne Brillouin Fiber Sensing System with Electrical Scanning

Proposed a novel scheme to measure the Brillouin frequency shift and power change, and analyzed the measurement accuracy of Brillouin frequency shift. The back Brillouin scattering light transfer to two electrical signals after heterodyne detection, one was used to measure the power in whole Brillouin spectrum, another was used to measure the Brillouin frequency shift. The Brillouin frequency shift can be precisely measured by changing the local frequency and adopting narrow filter.