單一與耦合帶線在有無接地貫孔中之時域及頻域分析

Abstract

隨著印刷電路板的多功能化，使得其電路設計變得更複雜，所需要的板層也愈多。在多層印刷電路板中，我們利用via來作為信號線於不同層板間的轉接。 在本研究中，首先探討在無ground via的情況下，信號於不連續轉接處傳輸時，如signal via，會產生非理想效應（如輻射損耗）。接下來討論當ground via增加時，對信號的傳輸有何影響。最後，探討在耦合帶線的結構中，ground via對於降低crosstalk的影響。我們利用HFSS軟體來模擬問題結構的頻域分析，及利用傅立葉轉換來作時域的分析。

As the functionality of the printed circuit boards (PCBs) increases, design of PCB becomes more complicated and the number of board layers required increases too. In a multi-layer PCB, vias are used as transitions for signal traces that have to jump from one reacting layer to a different layer. In this thesis, we first investigate the nonideal effects (e.g., radiation loss) generated by a discontinuous signal transition, such as a conventional signal via without any accompanying ground via. We then proceed to examine the effects of adding different number of ground vias surrounding each signal via. Finally, effects of ground vias on the reduction of crosstalks between two adjacent coax-stripline-coax structures are examined. In these examples, signal quality metrics (i.e., return/insertion loss and near/far-end crosstalks) are first analyzed in frequency using HFSS software package. Transfer function and inverse Fourier transformation techniques are then used to determine time-domain pulse propagation across various single- and coupled-line structures.