Visible light communication (VLC) is the possible solution to radio-frequency spectrum congestion problem due to its sufficient electromagnetic bandwidth. This thesis focuses on the PCB level design of transmitter in CMOS image sensor (CIS)-based VLC system with smart home control application and schematic level design of PD-based VLC system with traditional feed-forward equalization (FFE) as well as neural network (NN)-based equalization to solve limitations.

In the first part, an AC-powered driverless VLC lightbulb is designed to provide practical implementation of CIS-based VLC system. It is adopted as beacon to transmit unique ID code in proposed VLC enabled smart home control system, which aims to solve low control accuracy and security issues in RF-based systems. A smartphone with...[ Read more ]

Visible light communication (VLC) is the possible solution to radio-frequency spectrum congestion problem due to its sufficient electromagnetic bandwidth. This thesis focuses on the PCB level design of transmitter in CMOS image sensor (CIS)-based VLC system with smart home control application and schematic level design of PD-based VLC system with traditional feed-forward equalization (FFE) as well as neural network (NN)-based equalization to solve limitations.

In the first part, an AC-powered driverless VLC lightbulb is designed to provide practical implementation of CIS-based VLC system. It is adopted as beacon to transmit unique ID code in proposed VLC enabled smart home control system, which aims to solve low control accuracy and security issues in RF-based systems. A smartphone with control app serving as receiver works with cloud server to manage smart devices. A directional angle assisted indoor VLP algorithm for calculating user’s 3D location is adopted to further improve security and control accuracy.

In the second part, to improve the communication data rate and scale down VLC transmitter size, an integrated PAM-4 VLC transmitter with both digital and analog equalizations is proposed. A passive equalizer and digital FFE are adopted to extend the narrow bandwidth limited by LED. The highest transmission data rate of the proposed VLC transmitter is 1.2 Gbps.

In the third part, to overcome channel loss and further increase data rate, a PAM-8 VLC transceiver system which combines passive equalizer, NN-based FFE as pre-equalization and RBF-NN as post-equalization is presented. This VLC transceiver system is implemented in a co-simulation platform of MATLAB and Cadence with free-space and underwater channel models. This proposed VLC system can achieve the data rate of 3.6 Gbps with bit error rate of 3.8 x 10-3 with 3 m free space channel. The training time of RBF-NN is decreased for 86.7 % comparing with DNN.