Optical Wireless Communication (OWC) techniques are potential alternatives of the next generation wireless communication. These techniques, such as, VLC (visible light communication), OCC (optical camera communication), Li-Fi, FSOC (free space optical communication), and LiDAR, are increasingly deployed in our daily life. However, current OWC approaches are constrained by slow speeds and limited usage cases. The primary goal of this thesis is to boost the data rate of OWC with extended use scenarios and enable optical wireless sensing by exploiting the potentials on both the transmitter and receiver sides with designed effective strategies. We investigate the possibilities of various spatial-temporal dimensions (e.g., 1D, 2D, 3D, and 4D) as below.1D Temporal Optical Wireless Communication. We found that compensation symbols, which are commonly used for fine-grained dimming, are not used for data transmission in OOK-based LiFi for indoor lighting and communication. We exploit compensation symbol in 1D temporal diversity to address the conflict of fine-grained dimming and transmission. We intend to demonstrate the LiFOD framework, which is installed on commercial off-the-shelf (COTS) LiFi systems, to increase the data rate of existing Li-Fi systems. We utilize compensation symbols, which were previously only used for dimming, to carry data bits (bit patterns) for enhanced throughput. 2D Spatial-Temporal Optical Wireless Communication. In our study of camera-based OWC (i.e., optical camera communication), we first investigate 2D rolling blocks in the camera imaging process rather than 1D rolling strips for improved optical symbol modulation and data rate. Our proposed RainbowRow overcomes the limitation of restricted frequency responses (i.e., tens of Hz) in traditional optical camera communication. We implement low-cost RainbowRow prototypes with adaptations for both indoor office and vehicular networks. The results demonstrate that RainbowRow achieves a 20X data rate improvement compared to existing LED-OCC systems.3D Spatial Optical Wireless Communication. When compared to existing acoustic and RF-based approaches, underwater optical wireless communication appears promising due to its broad bandwidth and extended communication range. Existing optical tags (bar/QR codes) embed data in the plane with limited symbol distance and scanning angles. To address this limitation, we exploit 3D spatial diversity to design passive optical tags for simple and robust underwater navigation. We also develop underwater denoising algorithms with CycleGAN, CNN based relative positioning, and real-time data parsing. The experiments demonstrate that our U-star system can provide robust self-served underwater navigation guidance.3D Spatial Optical Wireless Sensing. The vision approaches compatible with time-consuming image processing for hand gesture reconstructing adopt low 60 Hz location sampling rate (frame rate). To overcome this limitation, we propose RoFin, which first exploits 6 spatial-temporal 2D rolling fingertips for real-time 20-joint hand pose reconstructing. RoFin designs active optical labeling for massive fingers with fine-grained finger tracking. These features enable great potential for enhanced multi-user HCI and virtual writing for users, especially for Parkinson sufferers. We implement RoFin gloves attached with single-colored LED nodes and commercial cameras.4D Spatial-Temporal Optical Wireless Integrated Sensing and Communication. Existing centralized radio frequency controlled from base stations face mutual interference and high latency, which causes localization errors. To avoid localization delay error, we explore optical camera communication for on-site pose parsing for drones. We exploit 4D spatial-temporal diversity (i.e., 3D spatial and 1D temporal diversities) for integrated sensing and communication. We propose PoseFly, an AI assisted OCC framework with integrated drone identification, on-site localization, quick-link communication, and lighting functions for swarming drones. The variety of applications in many contexts demonstrates OWC's potential and usefulness as a foundation for next-generation wireless technology. By leveraging the multiple dimensions of spatial-temporal diversities, we were able to successfully overcome some aspects of current OWC systems, delivering critical insights and discoveries for the future of optical wireless communication.
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