本論文提出一種雙向光纖通訊系統，利用分散式反饋雷射器(Distributed Feedback Laser, DFB)當作光源，由於DFB雷射的輸出光功率有限，因此我們使用摻鉺光纖放大器(Erbium-doped Optical Fiber Amplifier, EDFA)將光訊號進行放大，然後使用90%、10%分光器來分配光訊號給上傳以及下載路徑，電訊號則是使用5G基頻傳收機來發送正交分頻多工(Orthogonal Frequency Division Multiplexing, OFDM)訊號。
我們使用電光調變器(Electro Optical Modulator, EOM)將電訊號調變在光訊號上進行傳送，最後會使用光檢測器(Photodetector, PD)將光訊號轉換為電訊號，此時我們將此訊號接到5G基頻傳收機的接收端，利用MATLAB軟體來觀測此訊號的品質。
實驗結果表明，在短距離傳輸的情況下，星座圖的四個點都維持在一個很清晰的狀態，在長距離傳輸的情況下，依然還是可以看得到星座圖的四個點而不太模糊，代表著本論文所提出的雙向光纖通訊系統是可行的。

In this paper, We propose a bidirectional fiber-optic communication system, using a Distributed Feedback Laser (DFB) as a light source, because the output optical power of the DFB laser is limited, we use an Erbium-doped Optical Fiber Amplifier (EDFA) to amplify the optical signal, and then use 90% and 10% fiber-optic splitter to distribute the optical signal to the upload and download paths. The electrical signal uses 5G baseband transceiver to send Orthogonal Frequency Division Multiplexing (OFDM) signals.
We use the Electro-Optical Modulator (EOM) to modulate the electrical signal onto the optical signal for transmission, and finally use the Photodetector (PD) to convert the optical signal into an electrical signal, at this time, we connect this signal to the receiver of the 5G baseband transceiver, and use computer software to observe the quality of the signal.
The experimental results show that in the case of short-distance transmission, the four points of the constellation diagram are in a very clear state, in the case of long-distance transmission, the four points of the constellation diagram can still be seen without being too blurred, which means the bidirectional fiber-optic communication system proposed in this paper is feasible.

摘要.....i
Abstract.....iii
誌謝.....v
目錄.....vi
圖目錄.....viii
第一章 緒論.....1
1.1 前言.....1
1.2 研究動機與目的.....1
1.3 論文架構.....1
第二章 文獻探討.....2
2.1 OFDM-WDM-PON系統之相關技術.....2
2.2 WDM-PON系統之相關技術.....3
2.3 5G網路布建在環境中之相關技術.....5
第三章 系統元件介紹與原理.....6
3.1 分散式反饋雷射器.....6
3.2 摻鉺光纖放大器.....6
3.3 正交分頻多工.....7
3.3.1 調變技術.....8
3.3.2 保護區間(Guard Interval)與載波正交性.....10
3.3.3 誤差向量幅度.....14
3.3.4 頻率誤差.....14
3.4 電光調變器.....14
3.5 光檢測器.....15
3.6 光循環器.....15
3.7 光纖分光器.....16
3.8 光纖.....16
第四章 實驗內容與討論.....18
4.1 5G基頻傳收機與電光調變器之相關設定與量測.....18
4.1.1 5G基頻傳收機之相關設定與量測.....18
4.1.2 電光調變器之相關設定與量測.....20
4.2 雷射光源架構.....20
4.3 雙向光纖通訊系統之光源量測.....25
4.3.1 DFB雷射之量測.....25
4.3.2 DFB雷射經過摻鉺光纖放大器之量測.....26
4.3.3 DFB雷射經過摻鉺光纖放大器再經過分光器(90%、10%)之量測.....26
4.4 雙向光纖通訊系統架構.....29
4.4.1 短距離傳輸.....29
4.4.2 1km SMF長距離傳輸.....30
第五章 結論與未來展望.....33
參考文獻.....34
Extended Abstract.....36

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