本論文利用針對在光纖系統中，改變輸入雷射光的偏振狀態來降低因為非線性效應造成的四波混頻現象，此現象所造成的串擾(crosstalk)會惡化光纖的傳輸品質，對於一個10Gbps的六通道光纖通訊，可以發現在不同的輸入光源功率下，輸入雷射光源的偏振態相互線性正交化下，比起輸入光源皆為同一線性偏振態，平均下來可以降低接近10 dB的串擾並提升了傳輸品質。
另外，當輸入雷射光源偏振態依序相互正交圓偏振下，抗噪能力(降低6 dB串擾)也比皆為同一圓偏振態來的好。對於通道數量為三十二個時，也得到類似的結果。另外在考慮光纖雙折射現象和輸入光功率後，給定了一個最佳化的光纖參數設計。

This paper aims to reduce the crosstalk between the communication channels in a DWDM optical fiber system caused by the four wave mixing phenomenon of nonlinear optics effects by changing the polarization state of the laser input light. For a six channels (10 Gbps) fiber optic system, it can be found that compared to the input light are all with same linear polarization, when the polarization states of input light are linear mutually orthogonal, the crosstalk can be reduce almost 10 dB on average under different input powers. In addition, when the polarization states of input light are circular orthogonal (clock-wise vs. counter-clock wise, the noise immunity (reduce 6 dB) is better than when the input lights are all circular polarization. Similar results can be found for a thirty-two channels DWDM system. After considering the fiber birefringence and optical power, a set of optimized fiber design parameters are given.

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