I/Q Demodulator Based Optical Camera Communications

Visible light communications achieve wireless using sources such as lighting fixtures and electric signboards. The need to blink at high speed avoid flickering. However, the blinking frequency is much higher than frame rate of general-purpose cameras that are integrated into consumer devices smartphones. This paper proposes a method where principle I/Q demodulator employed in radio used estimate phase amplitude modulated sufficiently rate. achieved by two with slightly different exposure start timing estimating from pixel values light-emitting diode (LED) image one for each camera. In contrast conventional very short time, time can be increased, resulting efficiency capture. Additionally, we propose another configuration employing camera LEDs. An experiment verify communication possible proposed method, which 200 bits/s 60 frames per second cameras. We also confirmed methods have similar signal-to-noise ratio bit error performance.