臺灣博碩士論文加值系統

在波長多工光通信系統中，拉曼串音會劣化光信號品質。拉曼串音使信號功率由短波長的波道轉移至長波長的波道。可藉由適當的光放大器的增益改善此一現象。本論文研究使用拉曼串音補償光放大器對拉曼串音的改善。我們用數值解波動方程式求得輸出信號，再利用統計的方式計算信號錯誤率，即以Q 値來評估信統的傳輸品質。我們先求出拉曼補償的最佳週期。以此補償週期的增益值為準，加以調整各波道的放大器增益值，使得各波道Q值不致因拉曼串音而劣化。由此獲得最佳的拉曼串音補償光放大器之增益頻譜。

In the wavelength-division-multiplexing optical communication system, Raman crosstalk may degrade signal quality. Raman crosstalk causes the optical power of shorter wavelength signal transfer to longer wavelength signal. With the optical amplifiers of proper gain spectrum, the impact of Raman crosstalk can be reduced. This thesis studies the improvement of signal quality with Raman crosstalk compensation optical amplifiers. Wave equation is numerically solved to obtain the output signal. Bit error rate can be calculated by using statistic method. We judge system performance with Q factor. Firstly, an optimal compensation period is obtained. With this period, we adjust the gain spectrum so that the Q factor of each channel is not degraded by Raman crosstalk. Finally, the optimal gain spectrum for the Raman crosstalk compensation optical amplifiers is obtained.

目 錄
摘要 …………………………………………………………………i
Abstract ……………………………………………………………ii
致謝 …………………………………………………………………iii
目錄 …………………………………………………………………iv
圖目錄 ………………………………………………………………vi
表目錄 …………………………………………………………… viii
第一章 序論 …………………………………………1
第二章 理論背景 ……………………………………4
2-1 光纖波動方程式的探討…………………………4
2-2 光纖波動方程式的數值解討論…………………5
2-3 光纖中的線性效應 ……………………………6
2-4光纖的非線性效應 ……………………………7
第三章 傳輸系統架構……………………………… 10
3-1光纖傳輸系統參數………………………………10
3-2光纖傳輸系統的輸入信號……………………… 11
3-3光纖傳輸系統品質的評估……………………… 11
第四章 拉曼串音補償方法………………………… 13
4-1 拉曼串音數學模型的探討………………………13
4-2 拉曼串音現象在造成的影響…………………… 13
4-3 光放大器作動態增益和固定增益補償 …………14
4-4 光放大器增益擾動的影響…………………… 15
第五章 最佳化增益傾斜光放大器…………………16
5-1 光放大器增益的改變 ……………………… 16
5-2 固定光放大器增益的斜率對Q値的影響………17
5-3 改變光放大器增益的斜率對Q値的影響………17
第六章 討論與結論…………………………………19
參 考 文 獻…………………………………………20

參 考 文 獻
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[4] V. J. Mazurczyk, G. Shaulov, and E. A. Golovchenko,” Accumulation of gain tilt in WDM amplified systems due to Raman crosstalk,” IEEE Photon. Technol. Lett., vol. 12, p1531, 2000.
[5] W. Ding, Z. Chen, D. Wu, and A. Xu,” Asymmetry of Raman crosstalk in wavelength division multiplexing transmission systems,” Electron. Lett., vol. 38, p. 1265, 2002.
[6] 葉士俊“Raman Crosstalk Compensation with Optical Amplifiers
in WDM Optical Communication System” ，中華大學電機所光電組碩士論文，92年1月.