Compact NB BPF is using modified slow wave resonator with wide upper stopband

摘要

A compact narrowband band pass filter (NB BPF) with wide stop-band has been designed and fabricated. The presented filter based on modified slow wave resonator of microstrip is designed to achieve narrow bandwidth. The bandwidth of this filter capability of changing with the coupled lines is used in the middle of this structure filter. For the first time, by using transmission line theory and coupled line structure, the new design methodology of a narrowband BPF is employed and resonant frequency has been clearly explained. The filter has been designed for operating at center frequency 3.82 GHz, that suitable for WiMAX applications. The measured insertion loss (s21) and return loss (s11) are -0.38 dB and -33 dB, respectively at 3.82 GHz resonant frequencies. The proposed filter is designed, simulated and fabricated and the simulation results are in good agreement with measurement result. (c) 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:616-619, 2016