Performance Enhancement of Indoor VLC Systems Using DPSS-Based DCO-GFDM Modulation

Abstract

Visible light communication (VLC) is a promising solution for future wireless communication systems due to its high data rate, wide bandwidth, and enhanced security features. However, challenges such as high peak-to-average power ratio (PAPR) and out-of-band (OOB) spectral leakage limit its performance. In this study, we propose the integration of discrete prolate spheroidal sequences (DPSS) with direct current optical generalised frequency division multiplexing (DCO-GFDM) to enhance the performance of indoor VLC systems. A comparative analysis between traditional DCO-OFDM and the proposed DCO-GFDM scheme is conducted under both line-of-sight (LOS) and non-line-of-sight (NLOS) channel conditions. Simulation results show that the proposed method achieves approximately 2.5 dB reduction in PAPR and 45% reduction in OOB leakage compared to conventional DCO-OFDM, while maintaining a similar bit error rate (BER) performance. Moreover, the DCO-GFDM scheme demonstrates higher spectral efficiency without significant degradation in BER, achieving a BER below 10⁻³ at a signal-to-noise ratio (SNR) of 20 dB in both LOS and NLOS scenarios. These improvements underline the effectiveness of the DPSS-based approach in enhancing the reliability and spectral efficiency of indoor VLC systems.