Research On The Tuning Properties Of Microwave Photonic Filter Based On Stimulated Brillouin Scattering In Fiber

Microwave photonic filter technology is to modulate microwave signal to the optical carrier, to carry out frequency selection、suppression and wave shape processing of microwave signal in the optical domain, and it takes advantage of the light’s large bandwidth、low loss、 tunability、reconfiguration and so on, in order to achieve simplicity, low power consumption and excellent EMI performance of the microwave filter system. This article is based on research of Stimulated Brillouin Scattering (SBS) in fiber, to study its applications in the field of microwave photonic filter.First, it gave an analysis of the mechanism and the theoretical model of SBS in fiber, and researched the SBS gain spectrum measurement scheme based on a double-sideband suppressed-carrier modulation and a chirped fiber Bragg grating filter, tested and analyzed SBS gain spectrum properties with different pump powers. Second, built the SBS microwave photonic filter experimental system with DSF acting as the medium, and gave principle of the system to achieve a single band-pass microwave photonic filtering function. Finally, researched Brillouin frequency shift being10.513GHz on experiment; experimentally obtained1-6GHz single band-pass and tunable filtering function; experimental results showed that out of band rejection ratio could be improved by increasing the pump power and obtained the highest OBR of22.6dB. Work in this paper provided a useful reference for improving the microwave photonic filtering performance based on SBS in fiber.