由於電信產業中越來越高速的傳輸需求，差分線被廣泛的應用在傳輸訊號中，要符合好的訊號完整性（SI），縮小相鄰差分線之間的串間干擾，訊號傳輸才不會失真。
　　傳輸速率需求由25 Gbps進化到更高速，而因為印刷電路板的面積有限，所以佔大部分面積的訊號傳輸線尺寸大小佔了很重要的影響因素，為了克服這些挑戰，本研究提出以spoof surface plasmon polariton (spoof SPP) 的特性建立一組差分傳輸線，此方法不增加額外電路板面積又能減少差分訊號傳輸線之間的串間干擾。
　　另外，因高頻傳輸下傳輸線之間的串間干擾問題會越嚴重，探討100 gigabit/second (70 GHz)的傳輸速率下，使用低相對介電係數（relative permittivity）和低耗損正切（loss tangent）的印刷電路板（PCB）建立週期性結構差分線，採用 HFSS軟體有限元素分析法（FEM）模擬單一晶胞（unit cell）的色散關係以了解結構的色散特性，建立出單一晶胞結構的的幾何參數，因電腦資源有限，再以ADS軟體矩量法（MoM）數值分析完整類電表面電漿極化子（Spoof SPP）週期性結構差分對與另一組差分對之間的串間干擾s參數。
　　一般兩對差分線之間距離在小於三倍線寬時串間干擾S參數會大於-10 dB，且兩組差分線距離越靠近串間干擾問題會越嚴重，在不佔用PCB板額外空間的前提，本研究設計一個Spoof SPP結構差分線與另一對差分傳輸線在距離小於三倍線寬，70 GHz頻率下，串間干擾S63參數值小於-10 dB，改善了2.7 dB。

Owing to the demand of higher speed continues to increase in telecommunication industry, the differential pair is widely used in signal transmission. the issue in high-speed printed circuit boards (PCBs) that is crosstalk which was incurred by the coupling effect. In order to obtain good signal integral (SI) by minimizing the crosstalk between adjacent differential pair. That the output signal will not distortion is much important.
As the transfer rate higher than 25 Gbps is needed. Minimizing the size of transmission line became an important issue because of limited area of the PCB. To overcome the challenges, this research proposed a spoof surface plasmon polariton (spoof SPP) structure of differential pair. This method not only can avoid using much space of PCB but also reducing the crosstalk noise.
However, the crosstalk noise is serious because the frequency is higher and higher. We discuss the spoof SPP structure of differential pair for 100 gigabit/second transmission on low relative permittivity and low loss tangent PCB. The spoof SPP structure reduces the crosstalk at 70 GHz by the concept of spoof surface plasmon polaritons (spoof SPPs). It is found that the propagation frequency range of the unit-cell can optimize the geometric parameter. Numerical simulation is used to analyze the dispersion relation and the resonant frequency of unit cell and s-parameter of differential pair, then also compared with the conventional differential pair with the same size and separation. Hence the proposed spoof SPP differential pair can improve the crosstalk between the other typical differential pair, and the S63 parameter of crosstalk can smaller than -10 dB, that improved 2.7 dB.

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