Design of efficient and compact visible light communication using low-speed image sensor and MEMS mirror

Visible light communication (VLC) offers the usage of visible light for data transmission as well as illumination, and is suitable for vehicle-to-vehicle/infrastructure-to-vehicle communication. However, existing VLC systems require high-speed camera to achieve high data rate. To achieve VLC with sufficient data rate using commercial devices (e.g., smartphones), VLC using low-speed image sensor and MEMS mirror is proposed. In proposed technique, the transmitter emits modulated light pulses using an LED, and the receiver obtains the message using MEMS mirror and image sensor. Specifically, incoming light of fast blinking (time-domain signal) is scanned and converted to dotted and dashed lines (space-domain signal) by MEMS mirror, and image sensor can capture multiple bits per frame efficiently. The performance of the system was evaluated in experiments. The obtained results suggest that the proposed VLC system using low-speed image sensor and MEMS mirror could achieve data rate of 25 bps (frame rate of image sensor: 5 fps) with bit-error rate of 0 when signal-to-noise ratio was more than 5 dB.