利用外部光源注入技術改善 Fabry-Perot雷射二極體 光纖有線電視系統效能

Fiber Optical CATV System Performance Improvement by Using Fabry-Perot Laser Diode with External Light Injection Technique

廖育賢(Yu-Hsien Liao)

指導教授 ： 曾世杰 ； 呂海涵

國立臺北科技大學/機電學院/光電工程系所/碩士(2005年)

https://doi.org/10.6841/NTUT.2005.00278

摘要

在本論文中，我們共提出了三個系統架構，以外部光源注入的技術，探討光纖有線電視傳輸系統的特性。我們在第一個系統架構中，將外部光源注入Fabry-Perot雷射二極體中，以外部調變的方式來傳送美規NTSC的AM-VSB類比信號的77個頻道。我們利用外部光源注入技術提升Fabry-Perot雷射二極體的頻率響應，以改善系統之載波雜訊比、載波合成二次拍差比及載波合成三次拍差比數值。在第二個系統架構中，我們利用兩級光源注入方式來提昇長距離Radio on Fiber系統的整體性能，同時利用外部光源注入技術增加雷射的頻率響應（Frequency Response），並且增加半導體光放大器( SOA )輸出的增益飽和功率，如此一來可降低三階互調變失真( IMD3）及由於SOA增益飽和所引起的非線性失真。第三個系統架構中，我們利用一個4個頻道的分波多工(WDM)傳輸系統模擬256-QAM數位信號，經過80km單模光纖傳輸。在這個系統中，使用了四個1.3μm的光發射機串接上一個SOA的組合，在此WDM系統中能夠傳送252個256-QAM的數位模擬頻道，且其CNR> 38dB，BER<10-9。

關鍵字

外部光源注入技術 ； Fabry-Perot雷射二極體 ； 載波雜訊比 ； 合成二次拍差比 ； 合成三次拍差比

並列摘要

In this paper, we propose three fiber optical CATV systems. Firstly, an externally modulated AM-VSB CATV system that uses external light injection technique is proposed and demonstrated. External light injection technique enhances the frequency response of the Fabry-Perot laser diode, and thus improves the overall performance of the fiber optical CATV systems. Good performances of carrier-to-noise ratio (CNR), composite second order (CSO), and composite triple beat (CTB) were achieved with 0 dBm light injection. Secondly, a Radio-on-Fiber (ROF) transport system employing double external light injection techniques to improve systems’ performance is proposed and demonstrated. Simultaneously using external light injection techniques to enhance the frequency response of laser diode and increase the saturation output power of semiconductor optical amplifier (SOA), resulting in decreased third order intermodulation distortion (IMD3) and SOA gain-saturation-induced distortion. Thirdly, an externally modulated 1.3 µm simulated 256-QAM digital signals lightwave
long-distance transport system using semiconductor optical amplifier (SOA) and WDM
technique is proposed and demonstrated. This WDM system can transmit 252 simulated 256-QAM digital channels with CNR >38 dB to achieve a BER <10-9. Such a 1.3 µm series WDM transport system can potentially be used to help upgrade fiber penetration for those 1.3 µm optical transmitters in use today.

並列關鍵字

External light injection technique ； Fabry-Perot laser Diode ； Carrier-to-Noise Ratio ； Composite Second Order ； Composite Triple Beat

參考文獻

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