基於波長850奈米垂直共振腔面射型雷射之高速率距離乘積光連結系統應用非線性失真補償技術

隨著雲端服務與物聯網應用的出現，全球資訊量目前正在以爆炸性的速度成長當中，大型的數據中心也因應誕生，其規模可達數十個足球場的大小，因此，一個大型數據中心的耗電量是非常可觀的，然而傳統的電纜無法支持高速率以及低功耗的數據傳輸，所以目前數據中心採用了大量的光連結系統以達到高速傳輸與低功耗的目的。以波長850奈米重直共振腔面射型雷射搭配多模光纖為基礎的光連結系統主導了在短距離(小於300公尺)的應用，例如在數據中心內與高效能計算系統使用了大量的短距離光傳輸系統，這提供了更節能且有效率的資料傳輸，然而，在較長距離(大於500公尺) 的應用則會使用較長波段的雷射光源搭配單模光纖為主，但由於以單模光纖為主的光連結系統成本較高，因此，我們嘗試以多模光纖為主之光連結系統來傳輸更長的距離，以提供另一種較長距離傳輸的方案。因此，本研究成功以波長850奈米重直共振腔面射型雷射搭配多模光纖為基礎之光連結系統傳輸了長達2公里的距離，其中應用了四階層脈衝振幅調製格式與非線性失真補償技術成功達成高速率距離乘積之結果。

關鍵字

光連結；高速率距離乘積；垂直共振腔面射型雷射；非線性失真補償

並列摘要

According to the applications of cloud based services and Internet of Things (IOT), global internet traffic is explosive growing. It leads to the advent of large scale data centers and the size can equal to several football field. Hence, the power consumption of a large-scale data center is significant. So the current data current data centers employ lots of optical interconnects instead of electrical cable to achieve high-speed and energy-efficient data transmission. 850 nm Vertical-Cavity Surface Emitting Laser (VCSEL) based multimode fiber (MMF) optical link dominates applications in short-reach (< 300 m) area, such as interconnection within data center and high performance computing (HPC) which provides energy-efficient and effective data transmission. On the contrary, in longer-reach (> 500 m) area will utilize longer wavelength laser source with single-mode fiber (SMF). Because of the high cost of SMF based optical links, we try to employ MMF based optical interconnect to provide another solution for longer-reach transmission. In this work, we successfully demonstrate 2 km MMF transmission based on 850 nm VCSEL that utilizes 4-level pulse amplitude modulation (PAM4) and nonlinear equalization technique to achieve the result of high bit-rate distance product.

並列關鍵字

Optical interconnect ； High bit-rate distance product ； Vertical cavity surface emitting laser ； Nonlinear equalization

參考文獻

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