TITLE:
LED Modulation Characteristics in a Visible-Light Communication System
AUTHORS:
Yanrong Pei, Shaoxin Zhu, Hua Yang, Lixia Zhao, Xiaoyan Yi, Junxi Junxi Wang, Jinmin Li
KEYWORDS:
LED; Visible-light Communication (VLC); Modulation Characteristics; 3dB Bandwidth; Current Density
JOURNAL NAME:
Optics and Photonics Journal,
Vol.3 No.2B,
July
19,
2013
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.