一种毫米波微带带通滤波器的设计

摘要：基于小反射理论，引入Klopfenstein阻抗渐变线对传统发夹型谐振器结构进行改进，设计了一种相对带宽为8%的结构紧凑型毫米波带通滤波器。采用S参数的多项式综合方法得到耦合矩阵电路模型，利用三维电磁场全波仿真软件HFSS拟合出耦合系数与谐振器间距、外部品质因数与抽头位置的关系曲线，进而提取出耦合矩阵对应滤波器的物理尺寸。实测结果表明：在28.8GHz-31.2GHz频带内，该滤波器的插损小于3.0dB，回波优于-17dB，带外抑制大于40dB@33GHz，测试结果与计算结果吻合较好。

Design of Millimeter-wave Microstrip Bandpass Filter

Abstract: This paper introduces an efficient methodology for design of millimeter-wave microstrip Hairpin filter using improved resonator structure. The design procedure and some of the key parameter extraction methods is presented in detail. A millimeter-wave microstrip Hairpin filter of a 8% fraction bandwidth is designed with the aid of HFSS(High Frequency Simulator Structure). The filter has good performance, the insertion loss is less than 3dB and the return loss is better than -17dB for 28.8GHz to 31.2GHz, the out-of-band rejection levels is larger than 40dB at the frequency of 33GHz.The method of design can be refered for engineering.