Abstract
In general, visible light communication (VLC) uses LEDs
as transmitters. However, LEDs
can serve as receivers to construct a simple duplex VLC system that
uses only two LEDs instead of one LED and one photo-diode (PD). There
is a lack of effective equivalent analysis models for characterizing
and evaluating the inherent behavioral characteristics of LEDs used as
receivers. This paper presents an equivalent analysis model for GaN
LEDs as receivers. First, based on the proposed receiving equivalent
circuit model, a third-order signal transmission mathematical analysis
model is established, revealing the transmission relationship between
the photocurrent and output voltage. Further research is conducted on
the impact of parameter changes on the bandwidth, and the model can be
simplified into a first-order low-pass mathematical analysis model
under specific conditions, providing theoretical support for improving
the bandwidth of LED receiving applications. The experimental results
also confirm the theoretical predictions. This research result holds
significant importance for revealing the intrinsic mechanisms and the
improved optical communication performance of LEDs for effective
reception.
Funder
National Key Research and Development Program of China
National Natural Science Foundation of China