Real-Time Single-Channel 500 Mb/s Visible light communication using Pre-Equalizer and LMS adaptive Post-Equalization

Visible Light Communication (VLC) systems face a critical challenge in achieving gigabit-scale data rates due to the inherently limited modulation bandwidth of commercial LEDs, typically restricted to a few MHz. While prior works have explored pre-or post-equalization techniques individually, this paper presents a real-time, single-channel VLC system integrating a hybrid equalization architecture combining a zero-forcing (ZF) pre-equalizer and a least mean squares (LMS) adaptive post-equalizer. This synergistic approach uniquely addresses both static and dynamic channel impairments, enabling unprecedented bandwidth extension from a light emitting diode (LED) native 8.3 MHz to 100 MHz. Experimental results demonstrate a 500 Mb/s data rate over 1.55 m using OOK modulation, achieving a real-time bit error rate (BER) of 3.8 × 10 -3 —below the forward error correction (FEC) threshold—without offline processing. The scalability of the proposed system is further validated by attaining a data rate of 400 Mb/s over a transmission distance of 2.3 m, establishing state-of-the-art performance in both data rate and range.