水下無線光通訊系統技術（UWOC）

Underwater Wireless Optical Communication System Technology (UWOC)

劉彥良(Yen-Liang Liu)

《前瞻科技與管理》 8卷2期 (2018/11) Pp. 81-101

https://doi.org/10.6193/JATM.201811_8(2).0004

摘要

本篇報告針對水下無線光通訊技術進行說明，編排分為現行水下無線通訊類型，並針對水下無線光通訊分析國際案例以及工研院過去與未來發展。我們透過通道量測和水下直播應用技術開拓水下大頻寬通訊契機，設計了一個水下無線光通訊系統，製作了一個20公尺水下測試平臺，並在臺灣北部的野柳港進行實驗。使用頻譜正交頻分多工調變和位元分載演算法，驗證水下3公尺，收發距離10公尺傳輸系統，並實現白天158 Mbps和夜間205 Mbps的傳輸速率。未來我們將蒐集更多通道數據，建立訓練數據的標記、篩選以及預處理機制，針對光訊號在海水中的非線性失真效應進行訓練與補償機制，目標降低無線光通訊系統50%誤碼率。

關鍵字

水下無線光通訊系統 ； 正交頻分多工 ； 位元分載演算法 ； 非線性失真 ； 基於神經網絡的非線性補償

並列摘要

In this report, we introduce current communication technology on underwater wireless communication technology, including underwater wireless optical communication (UWOC). Additionally, analyzing international cases, we also present ITRI's (Industrial Technology Research Institute) development of UWOC technology over the past and the future. Aiming at large bandwidth communication demands through underwater channel measurement and underwater live broadcasting applications. First, we designed and fabricated an UWOC testing platform with a maximum distance of 20 m. Then, we conducted experiments in Yehliu Harbor in northern Taiwan. Using spectrum orthogonal frequency division multiplexing (OFDM) modulation and bit allocation algorithm, we achieved a transmission rate of 158 Mbps during the daytime and 205 Mbps during the nighttime at a transmission distance of 10 m. In the future, we will collect more channel data, establish the marking, screening and preprocessing mechanism of training data, and train and compensate the nonlinear distortion effect of the optical signal in seawater, aiming to reduce the 50% error rate of the wireless optical communication system.

並列關鍵字

underwater wireless optical communication (UWOC) ； orthogonal frequency-division multiplexing (OFDM) ； bit-loading algorithm ； Nonlinear distortion ； neural network-based nonlinear equalizer (NN-based NLE)

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