本論文提出了基於自注入鎖定架構之非對稱式雙向無線光通訊系統，此系統為了改善非對稱式雙向無線光通訊系統上行傳輸功率不足的問題，在系統端以自注入鎖定技術作為提升上行傳輸功率的方式，並使用空間光調變器作為動態繞射元件，使傳輸光束產生繞射角度，達到增加用戶端移動範圍的效果。而在用戶端方面更透過設計貓眼系統作為調變式復歸反射器，將上行光束接收並調變後以平行於入射光之路徑返回系統端做接收，可以免去用戶端準值系統的設置成本等問題，進而降低用戶端的體積與重量，增加系統的可攜帶性，達成無線光通訊中的雙向傳輸。從實驗之量測結果分析得知本論文所提之架構在使用C-band光源時可以達到線寬減小 0.08 nm、調變頻寬提升 9.82 GHz、側模抑制比為 26.58 dB、功率增益為 23 dB之效能。而鏈路速度在超過 1.5 Gbits / s的情況下進行上行與下行雙向鏈路數據傳輸，其品質因子皆超過12 dB。
此外本論文亦針對目前使用軌道角動量多工技術來增加上行通道傳輸容量之非對稱式雙向無線光通訊系統所可能面臨的通道衝突等問題提出一具有OAM交換功能之節點之設計來避免上行通道衝突的問題。透過本論文所提之設計不僅將能避免OAM通道衝突之問題產生並且亦能同時達成OAM通道交換之功能，預期將能成為未來實現非對稱式雙向無線光通訊系統不可或缺之關鍵性技術。

In this thesis, an asymmetric bidirectional optical wireless communication (B-OWC) based on the self-injection locking technique is proposed and experimentally studied. In order to improve the problem of insufficient uplink transmission power of the asymmetric B-OWC system, the self-injection locking technique was utilized at the access node (AN) to strengthen the power for uplink transmission. A liquid crystal spatial light modulator (LC-SLM) was also employed as a dynamic diffraction element to perform the beam steering functionality at the AN in order to improve the system coverage area. A cat's eye system was also designed to serve as a modulated retroreflector (MRR) at the terminal user (TU), where the incident beam is received, modulated, and reflected back to the AN via the path parallel to the incident beam, which will reduce the power consumptions, alignment difficulties, and cost of the TUs. In particular, the wavelength for uplink transmission and the modulation bandwidth used in each TU can be dynamically assigned by AN, which will simultaneously solve the problem of wavelength contentions and raise the efficiency of bandwidth utilization.
From the experimental measurement results, a linewidth reduction of 0.08 nm, a modulation bandwidth increments of 9.82 GHz, a side mode suppression ratio of 26.58 dB, a power gain of 23 dB have been achieved. Moreover, both uplink and downlink data transmission experiments with a link speed over 1.5 Gbits/s have also been experimental demonstrated successfully, with Quality factors (Q-factors) beyond 12 dB.
In addition, in this thesis we also proposed the use of orbital angular momentum multiplexing technique as a way to improve the transmission capacity of B-OWC, and we proposed a node with OAM channels switching function to solve the problem of OAM channel conflict. The design proposed in this thesis not only avoided the problem of OAM channel conflict, but also realized the function of OAM channel exchange at the same time, this design is expected to become an indispensable technology for realizing B-OWC in the future.

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