基于复合左右手传输线的LTCC滤波器设计

Design of a LTCC Filter Based on Composite Right/Left-Handed Transmission Lines

基于Caloz等人提出的复合左右手传输线结构,结合低温陶瓷共烧技术(LTCC)工艺特点,通过三维交指电容和接地带状线结构实现了多层复合左右手传输线(ML CRLH TL)谐振器。该结构将平面的交指电容转移到Z方向上,有效地减小了谐振器的尺寸。通过对谐振器结构特性的研究和分析,总结出各参量变化对中心频率、带宽及带内波纹的影响。在此基础上设计出了平面尺寸仅为2.4mm×1.0mm的可用于WALN的高性能ML CRLHTL带通滤波器。

Based on the composite fight/left-handed transmission line structure proposed by Caloz and combine with characteristic of Low-Temperature Co-Fired Ceramic （LTCC） technology, A LTCC resonator is proposed based on the hybrid resonant circuits, which is used a series 3-dimensional inter-digital capacitor and a shunt stub inductor. The plane inter-dig- ital capacitor of the structure is transferred to the Z direction, effectively reducing the filter size. Through research and analy- sis on the structural properties of this resonator, the impact of various parameter changes on the center frequency, bandwidth and band ripple is summed up. With particularly small size of 2.4mm×1. 0mm , the proposed ML CRLH TL filter, used in WALN application, demonstrates a good performance.