Orbital Angular Momentum Communication with Computer-Generated Holography for Free-Space Optical Links : 자유공간 광 링크를 위한 컴퓨터 생성 홀로그래피 기반 궤도 각운동량 통신

다국어 초록 (Multilingual Abstract)

This work presents a comprehensive orbital angular momentum (OAM)-based holographic communication system engineered for robustness in challenging environments. The experimental setup utilizes a meticulously defined optical environment with controlled turbulence, stable temperature, and minimal airflow to ensure repeatable testing conditions. Transmission employs a metasurface phase platform to encode OAM-carrying Laguerre– Gaussian (LG) beams. At the receiver, the system uses Fourier-plane optics, reflective separation, and a calibrated global-shutter camera for stable capture and angle-per-pixel mapping of the reconstructed fields. Captured optical frames are converted into packetized data streams, distributed across metasurface supergrids to form parallel transmission lanes, and processed with metadata for integrity checks.
The system achieves significant performance gains over conventional methods. For example, it demonstrates more than 10 times lower bit error rate in weak turbulence and maintains above 90 percent packet success in moderate turbulence. Compared to conventional systems, which saw forward error correction (FEC) drop below 5 percent, this system reduces the critical reacquisition time from tens of seconds to approximately 1 second. On the reconstruction side, the system preserves the normalized complex correlation above 0.8 in strong turbulence compared to 0.5 in conventional works. These results confirm that the integrated OAM-CGH framework achieves both communication-grade reliability and high- fidelity volumetric holographic reconstruction.

목차 (Table of Contents)

• 1. Introduction 1
• 1.1 Motivation 1
• 1.2 Research Objectives 3
• 1.3 Chapter Organization 4
• 2. Orbital Angular Momentum 6
• 2.1 Generation of Orbital Angular Momentum. 8
• 2.2 Holographic Structures 15
• 2.2.1 Metasurface-based Holographic Transmission 18
• 2.2.2 CCD-based Holography Interpretation 22
• 2.3 Related Works. 24
• 2.3.1 Optics and Photonics. 25
• 2.3.2 Other Related Fields 27
• 3. Optical System. 31
• 3.1 Optical Environments. 31
• 3.1.1 Beam Prerequisites. 35
• 3.1.2 Transmission Factors 41
• 3.2 OAM Transmitter and Receiver 47
• 3.2.1 Hologram Inputs 48
• 3.2.2 Receiving Optical Devices. 51
• 3.2.3 OAM Communication Optical Devices 54
• 3.2.4 Holographic Restructing Device 58
• 3.3 Communication Protocol 61
• 3.3.1 Data Transmission Protocol 63
• 3.3.2 Receiving and Restructuring Algorithm 66
• 3.4 System Interface 72
• 4. Simulation and Analysis 78
• 4.1 Simulation Setup. 78
• 4.2 Link Quality Assessment. 83
• 4.3 Holographic Structure Assessment 86
• 4.4 Overall Analysis 91
• 5. Conclusion 93