Hardware implementation of RF-to-Optical and Optical-to-RF converters for a laser-driven VLC system based on HackRF One SDR

The design and implementation of conventional Visible Light Communication (VLC) systems are generally hardware-based. The drawback of this approach is the difficulty of realization when the circuit is relatively complex, such as QAM, OFDM, and similar schemes. Furthermore, if design modifications are required, they must be carried out at the hardware level, leading to inefficiencies in both time and cost. In this study, the development of a Software-Defined Radio (SDR)-based VLC system is proposed, enabling VLC implementation through software. This research focuses on the realization of the RF-to-Optical and Optical-to-RF converters, which are part of the VLC system. For this purpose, two HackRF One SDR devices are used as the transmitter and receiver. On the transmitter side, the SDR’s RF output is converted into a laser light signal. On the receiver side, the incoming light is converted back into RF by the VLC receiver circuit. To evaluate system performance, a hardware-complex 4- QAM transceiver model is implemented entirely in software using GNU Radio. At 10 MHz, testing produced a data transfer rate of 100 kbps, an SNR of 17.83 dB, and a BER of 1.5 × 10−3.