基于S-DMS的谐波抑制双通带滤波器

Harmonic-Suppressed Dual-Band Band-Pass Filter Based on S-DMS

在传统微带线结构基础上利用阶跃阻抗并联短截线SISS(Step-Impedance Shunt Stubs)的带阻及慢波抑制特性,提出了一种新的基于SISS缺陷微带线结构S-DMS(SISS Defected Microstrip Structure),利用该结构设计制作了具有谐波抑制功能的双通带滤波器。采用HFSS进行仿真优化,在此基础上进行了实物加工,获得了通带中心频率为3.5 GHz,8.5 GHz,插入损耗分别为0.45 d B,2.7 d B,3 d B带宽分别是550 MHz,260 MHz,带外最大抑制小于-40 d B的实测结果,与仿真结果相当吻合。结果表明该双通带滤波器具有良好的谐波抑制能力、小带内衰减和宽且深的阻带特性。

On the basis of the traditional microstrip structure along with the rejection and slow wave suppression characteristics of step-impedance shunt stubs（SISS）,a new type of defected structure of microstrip line with SISS（S-DMS）was presented. A harmonicsuppressed dual-band band-pass filter was designed and fabricated employing the S-DMS and it was simulated and optimized by using HFSS. The physical filter was fabricated on the basis of simulation. It is observed that the dual-band band-pass filter operates at 3.5GHz and 8.5 GHz with insertion loss of 0.45 d B,2.7 d B. And the 3 d B bandwidth achieves 550 MHz and 260 MHz respectively.The measured results that the inhibit out-of-band is lower than to 40 d B,are consistent well with the simulation ones. The results exhibit that the dual-band band-pass filter has good harmonic suppression,small in-band attenuation and wide and deep stopband characteristics.