基于CSRR-QMSIW谐振器的双通带滤波器的设计

Design of Dual Passband Filter Based on CSRR-QMSIW Resonator

为满足滤波器在双频带通信系统中发展的要求,提出了一种基于1/4模基片集成波导(QMSIW)加载互补开口谐振环(CSRR)的新型双通带滤波器。根据CSRR谐振器的传输特性,实现以其谐振频点为中心的第一个通带;设计QMSIW谐振腔的边长,实现以该腔体谐振频点为中心的第二通带;设计QMSIW腔体间的耦合方式,在两通带之间和高阻带处各引入一个传输零点,加强两通带隔离度和带外抑制。设计了一款两通带的中心频率分别为8.1GHz和11.5GHz,且有效尺寸仅为15mm×8mm,插入损耗低于0.4dB,高阻带衰减达64dB,两通带隔离度达46dB。

To meet the development requirements of the filters in the dual-band communication system, a novel dual bandpass filter design method based on the quarter-mode substrate integrated waveguide (QMSIW) loaded complementary split ring resonator (CSRR) is proposed. Based on the transmission characteristics of the CSRR resonator, the first passband centered on its resonant frequency can be realized;the side length of the QMSIW resonator is designed to realize the second passband centered on the resonant frequency of the cavity. The coupling mode between QMSIW cavities is designed and a transmission zero points between the two passbands and at the high stopband are introduced respectively to enhance the isolation and out-of-band rejection of the two passbands. The center frequencies of a two passbands are designed to be 8.1 GHz and 11.5 GHz, respectively, and the effective size is only 15 mm× 8 mm, its insertion-loss is less than 0.4 dB, the high stopband attenuation is 64 dB, and the isolation between the two passbands is 46 dB.