現今，為了因應效能的提升，信號會需要透過多通道同時傳輸，而相鄰的信號線容易因電場與磁場的相互耦合，產生串音干擾的雜訊，且產品尺寸的縮小，使得干擾更加嚴重，此種干擾為影響信號完整性的主要因素，會使得系統的整體性能下降。過往大多使用3W法則與接地防護線來減少串音干擾，但隨著頻率的上升，抑制的效果逐漸下降，因此有學者提出加入開迴路諧振器在信號線間，其可不須貫穿孔結構且在特定頻率時有好的串音抑制效果，但僅對諧振器的長度對抑制效果的影響做探討。於是，本論文對開迴路諧振器進行更多結構改變的探討，改變了諧振器放置密度、諧振器間間距、諧振器與信號線間間距、諧振器開口、諧振器線寬和開口位置，利用HFSS模擬分析，結果顯示信號線間佈滿開迴路諧振器有較好的抑制效果，而當諧振器間間距、諧振器與信號線間間距、諧振器開口和諧振器線寬較小時，皆可增加抑制的效果，但是相對的抑制頻寬減少。並將其應用在四條信號線間，發現在多條信號線間，僅相鄰的信號線間能達到串音的抑制，若相隔兩條以上的線路則無抑制效果。本研究同時在1.6mm板厚的Fr4板上面進行開迴路諧振器的實作，量測確認實作與模擬結果一致。根據本研究的結果，諧振器的開口大小、線寬、諧振器間間距和諧振器與信號線間的間距皆會影響遠端串音的抑制效果，開口位置則無影響，進而提出開迴路諧振器的設計準則，讓應用開迴路諧振器在串音抑制上的設計更加方便。

Cross-talk is an important issue for the signal integrity of high frequency, high speed and multiple signal-transmission-lines in modern electronic products. Usually, 3W rule and guard trace between neighboring signal-lines are applied to reduce or suppress the effect of cross-talk. Both methods suffer a drawback that the effect of cross-talk increases with frequency. To alleviate the problem, open-looped resonators were introduced between signal lines recently and analysis showed that cross-talk could be greatly suppressed in low-frequency range and increased in high-frequency range. In this study, the effect and suppressing mechanism of open-looped resonators were investigated deeply by analyzing the cross-talk with varied design parameters, such as length of the resonators, size and position of the open gap, separation distance between two neighboring resonators or between the resonator and signal line, and number of resonators. Numerical results showed that open-looped resonators only affected the cross-talk between adjacent signal lines and had no influence on that of lines among which there was one or more other lines. The resonant frequency which separated the frequency range into the low-frequency section and high-frequency section was primarily determined by the length of the resonator. The size of resonator and separation distance could alter the available bandwidth of low-frequency section of suppression. Finally, real signal lines embedded with open-looped resonators were implemented to confirm the numerical results and a design rule of the resonators was proposed for practical applications.

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