DESIGN OF Li-Fi CURCUIT TO TRANSMET SOUND WAVE

Abstract

Today Wi-Fi (Wireless Fidelity) is used as wireless communication medium but Wi-Fi uses radio waves which are not allowed everywhere due to radio waves effect. Li-Fi (Light Fidelity) technology can be used in areas where Wi-Fi is not allowed. This technology will not only improve communication but also illuminate work place, and many public places. Li-Fi not only gives opportunity to create wireless communication but it also helps to save energy as technology uses LED (Light Emitting Diode) lights which consume very less electricity. The design of Worcester Polytechnic Institute team was used as a reference in this design, but the receiver circuit was changed with solar cell and computer speaker to allow it to receive an audio signal, and then the transmitter circuit was simplified. Firstly the audio signals that have been received at the end of the receiver were tested. The louder and most clear sound was received at distance 11cm between the transmitter and the receiver, and the receiver can receive signal until the distance became almost 60cm; this results was with a surround light. Then the experiment done in less surrounding light sources and the system transmit and receive signal until the distance become 1 meter. Secondly the signals from transmitter and receiver were tested by digital oscilloscope to compare about them. The signals from the transmitter and the receiver are similar on the wavelength and the frequency but different on the amplitude.