使用單一馬赫倫德爾調變器與光相位反轉技術應用於高密度分波多工系統長距離傳輸之研究與設計

Study and Design on Employing Single Mach-Zehnder Modulator with Optical Phase Conjugation Configuration for DWDM Long Haul Transmission System

林修聖(Hsiu-Sheng Lin)

指導教授 ： 賴柏洲

國立臺北科技大學/機電學院/電腦與通訊研究所/博士(2010年)

摘要

光纖通訊已發展至高傳輸速率與高傳輸容量之高密度分波多工系統(Dense Wavelength Division Multiplexing ; DWDM)，使用調變格式能有效減少因信號損失所產生之非線性效應、放大自發輻射與色散現象。在光纖通訊高密度分波多工系統中，歸零差分相位移相鍵控(Return to Zero Differential Phase Shift Keyed ; RZ-DPSK)調變格式具有較大之色散容忍度、較窄之頻寬、較低之非線性效應、簡單之系統架構與較低之系統成本。
本論文提出48 x 40 Gb/s高密度分波多工系統，使用單一馬赫倫德爾(Mach Zehnder Modulation ; MZM)調變器產生RZ-DPSK訊號搭配混合式拉曼/掺餌光纖放大器做為傳輸訊號提升，並且在傳輸之中間段，使用光相位反轉架構，補償色散損失、改善非線性效應，並探討系統之傳輸距離與傳輸效能。單一馬赫倫德爾調變器產生RZ-DPSK訊號，只需要單一馬赫倫德爾調變器搭配邏輯元件來代替傳統馬赫倫德爾調變器產生之脈衝訊號，因此能減少調變器之複雜度與減少系統之成本。
此提出48 x 40 Gb/s高密度分波多工系統之架構，使用單一馬赫倫德爾調變器產生RZ-DPSK訊號與搭配混合式放大器，在傳輸段使用單模光纖搭配色散補償光纖與大有效截面積光纖搭配反向色散光纖能各別地傳輸27個區段3240公里與28個區段3360公里。
在系統傳輸之中間段使用光相位反轉(Optical Phase Conjugation ; OPC)架構，半導體光放大器藉由四波混頻(Four Wave Mixing ; FWM)效應，能將功率信號提升13 dB，此增加之功率信號能補償累積色散之損失並改善非線性效應。因此，此提出之系統架構使用單模光纖搭配色散補償光纖與大有效截面積光纖搭配反向色散光纖，在傳輸段之中間使用光相位反轉架構，能各別地增加55%與64.2%之距離。
因此，本論文提出48 x 40 Gb/s高密度分波多工系統之架構，能成功地使用單一馬赫倫德爾調變器產生RZ-DPSK訊號，減少調變之複雜結構；與搭配混合式放大器，能提升傳輸之功率信號，並且在傳輸之中間段，使用光相位反轉架構，能補償色散損失、改善非線性效應與長距離傳輸之效能。

關鍵字

高密度分波多工系統 ； 歸零差分相位移相鍵控 ； 馬赫-倫德爾調變器 ； 光相位反轉 ； 四波混頻

並列摘要

The optical communication system developed into a high speed and high capacity Dense Wavelength Division Multiplexing (DWDM) system employing a modulation format which has an effective scheme to reduce signal impairments producing nonlinear effects, amplified spontaneous emission and dispersion phenomenon. The return to zero differential phase shift keying (RZ-DPSK) modulation format in DWDM optical communication system provides greater dispersion immunity, a narrow spectrum width, lower nonlinear effect, a simple scheme and reduces cost effectively.
In the dissertation, we proposed and demonstrated the 48 x 40 Gb/s DWDM system scheme employing single Mach Zehnder Modulation (MZM) RZ-DPSK modulation format with hybrid Raman/EDFA configuration to improve transmission signal, and employing an OPC configuration in the middle line that can compensate for dispersion impairment and improve nonlinear effects to investigate transmission distance performances. We proposed a novel scheme to generate an RZ-DPSK Signal, which needs only one MZM and the use of an electronic component to replace the pulse carving in a conventional second MZM that effectively reduces the modulation system complex at a lesser cost.
The 48 x 40 Gb/s DWDM system scheme employing single MZM RZ-DPSK modulation format and hybrid Raman/EDFA configuration using SMF with DCF and LEAF with RDF have a transmission of 27 spans over 3240 km and 28 spans over 3360 km, respectively.
In the middle of the transmission distance employing Optical Phase Conjugation (OPC) configuration, after SOA device by the Four Wave Mixing (FWM) effect, the power signal promotes 13 dB. The increased power can compensate for the accumulated dispersion impairment and improve nonlinear effects.
Therefore, the 48 x 40 Gb/s DWDM system scheme using SMF with DCF for the fiber transmission section and LEAF with RDF for the fiber transmission section employing OPC configuration in the middle line, the transmission distance increased by 55% and 64.2%, respectively.
The proposed 48 x 40 Gb/s DWDM system scheme successfully employs single MZM RZ-DPSK modulation format to reduce modulation complex configuration and employs hybrid Raman/EDFA configuration to promote the power signal. In the middle line employing OPC configuration that can compensate for dispersion impairment, improve nonlinear effects, and promote power optical spectrum signal for long haul optical transmission.

並列關鍵字

Dense Wavelength Division Multiplexing (DWDM) ； Return to Zero Differential Phase Shift Keying (RZ-DPSK) ； Mach Zehnder Modulation (MZM) ； Optical Phase Conjugation (OPC) ； Four Wave Mixing (FWM)

參考文獻

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