Experimental Study on the Impact of Blue Filtering and Equalization in OOK-NRZ White LED Visible Light Communication Systems

Authors

Keywords:

Optical Filtering, Signal Equalization, Eye Diagram, Thermal Stability, Data Throughput

Abstract

Visible Light Communication (VLC) offers a high-bandwidth, energy-efficient, and license-free medium for wireless data transmission using white LEDs. However, performance is limited by the phosphor’s slow response and temperature sensitivity, which reduce modulation bandwidth and signal integrity. This study experimentally investigates improvements in a white LED-based VLC system using On-Off Keying Non-Return-to-Zero (OOK-NRZ) modulation through blue optical filtering and passive electronic equalization. The system was tested under data rates from 0.5–20 MHz and varying drive currents. A blue optical filter suppressed slow yellow phosphor components, while an R//C equalization circuit mitigated inter-symbol interference (ISI). Results show that blue filtering enhances high-frequency stability and extends modulation bandwidth, while equalization improves signal fidelity and eye diagram opening. Optimal performance was achieved at a driving current of 200 mA, balancing signal quality and thermal stability. These findings demonstrate that combining blue filtering and equalization provides an efficient, low-cost approach for improving data throughput and reliability in white LED-based VLC systems, enabling practical indoor communication and smart lighting applications.

Dimensions

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Normalized Received Signal (dB) vs. Frequency (MHz) for White and Blue Light

Published

2025-10-30

How to Cite

Magaji, A. B., Ikechiamaka, F. N., & Akinbolati, A. (2025). Experimental Study on the Impact of Blue Filtering and Equalization in OOK-NRZ White LED Visible Light Communication Systems. Nigerian Journal of Physics, 34(4), 101-106. https://doi.org/10.62292/10.62292/njp.v34i4.2025.449

Issue

Vol. 34 No. 4 (2025): Nigerian Journal of Physics - Vol. 34 No. 4

Section

Articles
Copyright & Licensing

How to Cite

Magaji, A. B., Ikechiamaka, F. N., & Akinbolati, A. (2025). Experimental Study on the Impact of Blue Filtering and Equalization in OOK-NRZ White LED Visible Light Communication Systems. Nigerian Journal of Physics, 34(4), 101-106. https://doi.org/10.62292/10.62292/njp.v34i4.2025.449

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