本論文提出非對稱via補償的強耦合差動傳輸線，可以有效地降低轉角差動傳輸線所產生的共模雜訊以及差模反射。適當地設計非對稱via來補償強耦合差動傳輸線的內外路徑差，可以有效地降低輸出端的共模雜訊，同時，適當地設計非對稱via達成阻抗匹配，可以降低輸入端的差模反射。在頻域方面，7 GHz以前差模轉共模的模轉換皆在-20 dB以下；在時域方面，TDT共模雜訊從0.038 V減少至0.016 V。
為了簡化設計，我們提出寬邊平行耦合傳輸線的架構，這個架構為平衡的架構，因此輸出端的模轉換本身就很低，只要適當地設計阻抗匹配，就可以使輸入端的差模反射達到很低的位準。在頻域方面，差模轉共模穿透量與差模轉共模反射量皆在-30 dB以下，而差模到差模反射量在-20 dB 以下；在時域的方面，TDR差模雜訊從0.06 V降低至0.024 V，TDR共模雜訊從0.015 V降低至0.005 V，TDT共模雜訊為0.001 V。

In this thesis, a tightly-coupled multi-layer differential transmission line using the unsymmetrical differential vias is proposed. The proposed structure could effectively reduce the differential-to-common mode conversion and differential-to-differential mode reflection. By adequately designing the unsymmetrical differential vias to compensate the path difference between the inner and outer paths of the differential transmission line, the common-mode noise at the output port could be greatly reduced. Meanwhile, by adequately designing the unsymmetrical differential vias to match the system impedance, the differential-mode reflection at the input port could be greatly reduced. As can be seen from the frequency-domain results, the differential-to-common mode conversion is less than -20 dB from DC to 7 GHz. As can be seen from the time-domain results, the TDT common-mode noise is reduced from 0.038 V to 0.016 V.
In order to simplify the design procedures, a multi-layer differential transmission line using the broadside-coupled line is proposed. Since the proposed structure is a balanced structure, the differential-to-common mode conversion at the output port would eventually be very low. By adequately designing the broadside-coupled line to match the system impedance, the differential-to-differential mode reflection at the input port could be greatly reduced. As can be seen from the frequency-domain results, the differential-to-common conversion and reflection are all less than -30 dB while the differential-to-differential mode reflection is less than -20 dB. As can be seen from the time-domain results, the TDR differential-mode noise is reduced from 0.06 V to 0.024 V; the TDR common-mode noise is reduced from 0.015 V to 0.005 V; the TDT common-mode noise is reduced to 0.001 V.

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