A Novel Method for Constructing VLC Equalizer With Active-Passive Hybrid Network

Abstract

In this article, a novel method for constructing a pre-equalizer by optimized filter synthesis with vector fitting is proposed to broaden the bandwidth of a visible light communication (VLC) system. By using the proposed method, an active-passive hybrid equalization circuit is constructed, and it is demonstrated that the 3-dB bandwidth of the VLC system with commercially available phosphorescent white LED is extended from 30 MHz to 600 MHz. A 1.35 Gb/s NRZ-OOK VLC transmission over 12 cm free space transmission distance is experimentally realized, achieving a bit error rate (BER) of $\text{8.8} \times \text{10}^{-\text{5}}$. To the best of the authors knowledge, this is the largest reported 3-dB bandwidth and real-time data rate achieved in the VLC system with a single commercially phosphorescent white LED.

Keywords

• VLC
• pre-equalization circuit
• vector fitting
• filter synthesis
• bridge-T structure.