利用等效LC谐振电路, 分析了开口环的谐振频率与等效电路电参数之间的关系. 区别于传统微带传输线及附属开口环结构, 本文设计了两种以开口环作为传输媒介的结构.对两种结构仿真和实验测试,实现了带宽分别为300MHz和200MHz的带通滤波器的设计,并在开口谐振环外环一侧加载变容二极管及偏置电路实现通带频率的连续可调. 从表面电流密度分别分析了两种结构的传输特性, 在通带内, 方环的传输系数比圆环高3dB,其中结构之间的等效间距是影响传输效率的一个重要因素.

Based on equivalent LC resonant circuit, the response between the resonance frequency and the electric parameters of the equivalent circuit were analyzed. Different from the traditional transmission line loaded with split-ring resonator structure, two different split-ring resonator structures were designed as the transmission medium. In consequence, two passband filters are achieved in this paper which bandwidth are 300 MHz and 200 MHz with square and circular split-ring resonator respectively, by loading with varactor and bias circuit in the split-ring resonator structure, two continuous tunable passband filters are finished in the end. The difference in surface current density between the square and circular split-ring resonator is given in this paper, the transmission coefficient of the square split-ring resonator is 3dB higher than the circulal’s within the passband, analysis shows the effective distance is one of important reason for the coupling efficiency.