Wu Xiao-jun,Zhang Ai-ling.A tunable microwave photonic filter with complex coefficient based on slicing spectrum and stimulated Brillouin scattering[J].Optoelectronics Letters,2012,8(5):340-343 A tunable microwave photonic filter with complex coefficient based on slicing spectrum and stimulated Brillouin scattering Author Name Affiliation Wu Xiao-jun  Key Lab. on Film Electronics and Communication Devices of Tianjin, Communication Devices and Technology Engineering Research Center, Ministry of Education of China, Tianjin University of Technology, Tianjin 300384, China  Zhang Ai-ling  Key Lab. on Film Electronics and Communication Devices of Tianjin, Communication Devices and Technology Engineering Research Center, Ministry of Education of China, Tianjin University of Technology, Tianjin 300384, China  Abstract:       In this paper, we propose a method to realize microwave photonic filter (MPF) with complex coefficient, whose central frequency f 0 and 3 dB bandwidth are tunable. The complex coefficient is realized by multi-wavelength optical source and stimulated Brillouin scattering (SBS). The central frequency of the filter is tuned by adjusting the phase shift caused by SBS without changing its frequency response. The frequency selectivity of filter can be improved through increasing the bandwidth of broadband optical source (BOS) or decreasing wavelength separation to increase the taps of MPF. The mainlobeto-sidelobe suppression ratio (MSSR) of the filter is affected by the weight of each tap. When the length of fiber is 0.5544 m in birefringence fiber loop mirror (FLM), the MSSR is improved by 18.55 dB compared with that without the weight controlling. Hits: 6919 Download times: 656 This work has been supported by the National Natural Science Foundation of China (No.60808004). View Full Text    Download reader