一种小型化宽阻带窄带通滤波器研究

为实现滤波器设计小型化，降低带通滤波器的高次谐波干扰，本文结合传统的1/4波长谐振器结构，采用在谐振器微带线上添加开路线的方法，降低高次谐振频点处的插入损耗，消减谐波影响。相比半波谐振器，1/4波长谐振器能有效地减小滤波器尺寸，此外开路线的添加除具有消减高次谐波作用，同时还能降低基频谐振点，促进设计小型化。通过仿真软件对该方案的验证及网络分析仪的实物测试表明，此方案具有良好效果，能广泛应用于窄带通滤波器小型化及谐波抑制。

Research of miniaturized Wide Stopband Narrow Bandpass Filter

In order to realize the miniaturization and reduce the influences of high order resonant frequencies in bandpass filter design, based on the traditional 1/4 wavelength resonance structure, this paper adopts to add open stubs embeded on the resonator to reduce the insertion loss at suitable frequencies and achieve the spurious suppression. Compared to the 1/2 wavelength resonator, the 1/4 wavelength resonator has great advantage of reducing the design size. In addition, the open stubs embeded have not only the effect of reducing the insertion loss but also the one of reducing the bandpass frequency to achieve the design miniaturization. The simulation by HFSS software and the measurement of fabricated prototype Based on the proposed topology demonstrate the designed filter available and can be applicated in spurious suppression and miniaturization design of bandpass filters.