Extension of a 3-cm range of transmission and reception of a visible light communication system through varying modulation technique

This paper presents the use of visible light as a means of data communication, utilizing a Light Emitting Diode (LED) for data transmission, specifically the super bright LED and utilizing a Laser diode (LD) module which has a more focused beam and further range. The study implemented a wireless visible light communication (VLC) system that can transmit and receive data with a range of more than 3 cm; through varying modulation techniques, namely Phase Shift Keying (PSK), Frequency Shift Keying (FSK) and, Amplitude Shift Keying (ASK). The process includes using two Arduino modules, one for signal transmission and another for signal reception. The transmitter module is connected to a computer with the Arduino software where data will be inputted for transmission. The receiver consists of a photodiode which sends the intelligence to the Arduino and projects data to the screen. In all of the said techniques, it is observed that the presence of Bit Error Rate (BER) increased as the distance between the transmitter and receiver becomes greater. The farthest distance that PSK can achieve for LED is 9.8 cm and 22.2 cm for laser. In FSK the limit is up until 9.4 cm for LED and 21.4 cm for laser. While in ASK, the BER is unacceptable for all the distances in LED but in using the laser, it can reach as long as 19.4 cm. In general, the researchers were able to extend the transmission distance far greater than 3 cm. minimum distance between the devices.