隨著雲端、AI、 IoT等應用的擴張，寬頻無線通訊的需求正快速提升。為了因應高速傳輸的頻寬需求，5G開始將頻譜規劃拓展到毫米波(Millimeter-wave，mm-Wave)的範圍。隨著接續而來的B5G (Beyond 5G)乃至6G的傳輸需求展望，上至THz的頻譜規劃也正被廣泛討論。相較於無線電，無線紅外光通訊基於其寬頻、可重複利用光纖通訊元件等優勢，也被視為是未來無線通訊的熱門的可能方案。基於光纖通訊元件的雷射具有高指向性的特性，為了支援不同位置或移動的用戶，有效的beam-steering技術是相關應用的重要關鍵。

本論文研究實現室內高速無線光通訊系統的相關技術。本論文提出並設計一種新型的光束控制模組，該模組支援500 kHz的beam-steering隨機掃描速率，可以有效將光束導向不同位置的用戶。本論文進一步搭建一套使用該模組的全雙工無線紅外光傳輸系統，並利用iPerf3軟體分析不同光束切換條件對系統傳輸容量的影響，實驗證實於本實驗架構中以500 kHz的光束切換速率，同時連續切換1000次後，仍可以維持通訊的穩定性。該系統成功實現100 Mbps的實時雙向訊號傳輸，並達成同時對兩個用戶進行HD影片的串流服務。

Applications like virtual reality (VR), holographic display, and artificial intelligence (AI) are pushing the signal capacity for wireless communications. In order to get the corresponding transmission bandwidth, spectrum up to the millimeter-wave has been allocated in 5G; and even higher spectrum towards the THz range is also actively discussed for the B5G (Beyond 5G) and coming 6G systems. Compared to the radio technologies, infrared optical wireless communication (IR-OWC) has abundant spectrum resources and can directly re-use the high-speed device available for the fiber-optic communication systems; hence it is extensively studied as a solid option for the wireless applications. Lasers used for IR-OWC typically have directional beams, so specific beam-steering technologies are crucial for the mobile services.

A fast beam-steerable IR-OWC system is studied in this thesis. The beam-steering criteria for the system is firstly analyzed. The corresponding lens is then applied to the designed beam forms. The lens is used in a novel beam-steering module proposed in this thesis. With the module, a beam-steerable full-duplex IR-OWC system is built. We demonstrate simultaneous distributions of independent HD video streams towards two separate users, and a random beam-steering rate of 500 kHz under 100 Mbps real-time transmission speed.

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