接地金属化孔对交指带通滤波器频响的影响分析

用微带线结构实现有接地端的交指带通滤波器时,接地金属化孔的寄生电感效应将影响带通滤波器的幅频特性。寄生电感的大小可由经验公式近似计算,借助于三维电磁场仿真软件,可以计算出当接地金属化孔的排列方式不同时,由寄生电感引起的带通滤波器中心频率偏移量也不同。接地金属化孔排列引起的寄生电感越小,带通滤波器的中心频率越接近于理论值,因此在设计有接地金属化孔的交指带通滤波器时,需根据所选用的金属化孔排列结构修正滤波器中心频率的偏移。

Analysis of Grouding Via Holes Influenced the Frequency Response of Interdigital Bandpass Filter

When interdigital bandpass filter with grounding ends is designed for microstrip implementa-tion,the parasitic inductance of grounding via holes inevitably influences frequency response of bandpass filter.Equivalent inductance of isolated grounding via holes is computed by approximate formula,howev-er,availability of 3D electromagnetic field solver provides an opportunity to analyze the center frequency shift of bandpass filter with different form of grounding via holes.Small parasitic inductance is often u...