Abstract:Based on the study of erbium-doped fiber(EDF) and fiber Bragg grating(FBG), a microwave photonic filter based on erbium-doped fiber loop with FBG was put forward. The transfer function of the microwave photonic filter was derived according to its signal flow graph. And then the effects of coupling coefficient, the gain of the erbium-doped fiber, the reflectivity of the fiber Bragg grating and the length of the fiber ring on the transmission characteristics of the system were discussed. Theoretical calculation and simulation analysis indicate that the best filtering effect of the microwave photonic filter can be obtained when the coupler factor is 0.5, the gain of the erbium-doped fiber is 2 and the reflectivity of the FBG is 1.