The Optimization Design of High Q Microwave Photonic Filters Based on Cascade Fiber Bragg Gratings

Quality factor is one of the most important indicators of measuring microwave photonic filter performance and the optimization of microwave photonic filter has been a change area recently. In this paper, a novel one order infinite response microwave photonic filter (OO-IIRMPF) model is built, and the structure of Fiber Bragg Gratings (FBGs) with the erbium doped fiber pair is proposed. By simulating the amplitude response and optimizing the parameters, the conclusion that the infinite quality factor can be realized theoretically is obtained, and the condition is that the product of the weighting coefficients of feedback loops should be equal to 1. Moreover, the infinite impulse response (IIR) filter cascade system and finite impulse response (FIR) filter cascade system are constructed and compared to find the best filter parameters. The microwave photonic filter with high Q value designed in this paper has the virtue of simple structure and lower cost.