C-Band掺鉺光纖放大器其增益穩定特性對傳輸信號動態特性之探討

Dynamic Transmission Performances of C-Band EDFA Based on Feedback Gain-Clamping Stability

李志勇(Chih-Yung Li)

指導教授 ： 何文章

國立臺北科技大學/電資學院/光電與通訊產業研發碩士專班/碩士(2010年)

摘要

摻鉺光纖放大器(EDFA) 具有輸出功率大、增益高、寬頻寬、雜訊低、對偏振不敏感等優點，是光通訊系統關鍵主件之一。近年來使用的DWDM（Dense Wavelength Division Multiplexing）技術能有效使用傳輸頻寬，因此DWDM系統使用之光放大器時必須考慮能用的頻寬增加外，也要考慮提供給各個通道增益要平坦一致與通道數量增減變化所造成光放大器對傳輸信號影響。因此EDFA的增益穩定及平坦化就成為一個相當重要的特性。
在本論文探討增益箝制EDFA (GC-EDFA)的增益特性，及量測不同數量及不同形式之傳輸信號經過此光放大器的動態特性。本實驗架構：以光耦合器、光循環器、及可調光衰減器所組成的環狀雷射腔，並在放大器輸出端使用布拉格光纖光柵(FBG)，建構出一C-Band GC-EDFA，此架構之光放大器可以得到良好的增益箝制及增益平坦特性。當調整可變衰減器之衰減量為5 dB時，測量輸入信號功率從-35 dBm ~ -10 dBm，可得到增益被箝制在16.2 dB，且增益變化量小於 ±0.26 dB。信號波長範圍在1530 ~ 1560 nm時，增益變化量也可控制小於0.13dB，可作為16個分波多工通道波長，提供優異之增益箝制及平坦的放大功能。

關鍵字

摻鉺光纖放大器 ； 增益箝制 ； 光增益 ； 雜訊數值

並列摘要

EDFA is a key component of optical communication, which with advantages of high output power, high gain, wide bandwidth, low noise and low polarization sensitivity. Because DWDM technology can be use for broad bandwidth to transmit signals efficiently, the optical amplifier for DWDM system need not only provide more bandwidth and consider the flatness of gain and variation of gain for all channels when add or drop some channels. So the stability and flatness of gain for EDFA are important characteristics in DWDM system.
In this thesis, we are focus on gain characteristic and gain stability when signal transmit on C-Band GC-EDFA system. A C-Band gain clamped erbium-doped fiber amplifier (C-Band EDFA) based on a ring laser cavity is demonstrated using a fiber Bragg grating (FBG) at the output end of the amplifier. The design provides a good gain clamping as well as a gain flattening. The gain is clamped at 16.2 dB with gain variation ±0.26 dB when input signal power of -35 dBm to -10 dBm by setting the VOA=5 dB. Also, the amplifier has the flattest gain spectrum at VOA = 5 dB. The gain variation is less than 0.13 dB within the wavelength range from 1530 nm to 1560 nm. This gain clamped amplifier also can support a 16 channel WDM system.

並列關鍵字

EDFA ； Gain-Clamping ； Gain ； Noise Figure

參考文獻

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