Tackling the ever-increasing demands on the electromagnetic spectrum from a proliferation of connected devices while enabling the supportive communication infrastructure for new technology is crucial to continuing technological advancement in the 21st century. There is a critical need for intelligent transportation systems (ITS), not only to enable autonomy, but to improve the safety and efficiency of vehicles on roadways. Visible light communication (VLC) offers an attractive and relatively untapped solution to complement or replace radio frequency communications in vehicles and connected devices. This work explores a low power, low complexity, flicker-free VLC system operating outdoors in full daylight from 5 m to 550 m using a digital polarization modulation scheme. A delaminated LCD computer monitor and an Android smartphone with monoscope were employed as low-cost representative components, successfully transmitting frames at varying ranges from 5 m out to 550 m outdoors at midday in Monterey, California. Received signal performance with 26 cd of transmitted optical power ranged from 36 dB to 9 dB SNR at 5 m out to 550 m, respectively, providing throughput at greater ranges than seen in other outdoor VLC literature. These tests demonstrate the successful implementation of a VLC polarization modulation imperceptible to human vision that remains robust to solar noise at 550 m using very low transmitted power. Such a system could enable dual utilization of vehicle lights both for illumination and communication in an ITS, and is extendable as a low-cost, high-efficiency physical layer encoding for many other connected devices.
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