Frequency response comparison of photo-detectors for visible light communication systems

Abstract

For Visible Light Communication (VLC) systems, photo receiver is very important for obtaining low noisy modulated signal at receiver side since the pure modulated signal is easy demodulated. Therefore, we give a comparison of performance of three type photo receivers in this paper. In first application, we use a photoresistor to detect the modulated signal. It is referred as CDS (cadmium-sulfide) resistor. Another detector is solar cell unit. The other receiver is selected photodiode detector. It is shown from experimental results that the most appropriate modulated signal is obtained at output of photodiode. The output of solar cell consists of very complex signal compared with output of photoresistor. Additionally, we use PPM (Pulse Position Modulation) technique for transmission of data signal. © 2018 Trans Tech Publications, Switzerland.