Yanrong Pei, Shaoxin Zhu, Hua Yang, Lixia Zhao, Xiaoyan Yi, Junxi Junxi Wang, Jinmin Li
Institute of Semiconductors, Chinese Academy of Sciences, Beijing, China.
DOI: 10.4236/opj.2013.32B034   PDF    HTML     10,582 Downloads   17,470 Views   Citations

Abstract

This paper conducts a research on modulation characteristics of blue light-emitting diodes (LEDs) used in a visible-light communication (VLC) system. Through analysis of the modulation characteristics of LEDs with different emitting sizes, we find that there is a similar linear relationship between LED’s 3dB bandwidth and the operation current density. This experiment also shows that high series resistance is one major issue that limits our LED's modulation speed. To further improve the LED bandwidth, the resistance can be reduced by optimizing device layout as well as reducing material bulk resistance. Clearly, this study provides an approach to increase the modulation bandwidth of GaN-based LEDs for VLC systems.

Keywords

LED; Visible-light Communication (VLC); Modulation Characteristics; 3dB Bandwidth; Current Density

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Conflicts of Interest

The authors declare no conflicts of interest.

References

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