Frequency domain anti-flickering in visible light communication system

Baozhu Wang, Wenjing Sun, Jian Chen, Changyuan Yu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)

Abstract

Light emitting diodes (LED) is a promising device in visible light communication (VLC), enabling simultaneous illumination and data transmission via visible light. However, the generation of modulated visible light signals causes variation to the LED intensity in intensity modulation/direct detection (IM/DD) transmission, which may cause flickering — the fast blinking of the LED (when signals are below 200 Hz). Flicker may cause migraines, headaches, and even repetitive behavior among persons with autism. Therefore, flicking mitigation approaches must be applied for VLC with simultaneous illumination scenarios. While the optimization of the LED driving circuit and encoding can be employed to reduce flickering, driving circuit dramatically increase the system cost and communication requirements are usually excluded. As to encoding methods, they will result in reduced data rate and hardware overhead, leading to performance bottlenecks. In this paper, we proposed a signal processing method in the frequency domain to mitigate LED flickering. Low-frequency components (3–70 Hz) of modulated signals are extracted by using Fourier transform and inversely restored for transmission. Besides flickering, it is shown that interference caused by other artificial light sources can also be mitigated with the proposed method. Simulation results show that by applying the proposed frequency domain signal processing technique, communication performance of the system is enhanced with the cancellation of interference while flicker is reduced significantly. Under the condition of a 13 dB signal-to-noise (SNR) ratio, the bit error rate can reach the order of 10−3.

Original languageEnglish
Article number128203
Pages (from-to)1-8
Number of pages8
JournalOptics Communications
Volume516
DOIs
Publication statusPublished - 1 Aug 2022

Keywords

  • Frequency domain
  • LED flicker
  • Signal processing
  • Visible light communication

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics
  • Physical and Theoretical Chemistry
  • Electrical and Electronic Engineering

Fingerprint

Dive into the research topics of 'Frequency domain anti-flickering in visible light communication system'. Together they form a unique fingerprint.

Cite this