A VLC-Based Location System for Mobile Application

Abstract: Visible light communication is the new technology with more benefits over an existing radio frequency communication system such as high security, high energy, efficiency and long life. The primary aim of LED is illumination which is important requirement of VLC system. White light can be used in both indoor and outdoor applications for illumination as well as data transmission because colours of objects as seen closely resemble under both the white light and natural light. The proposed VLC system enables indoor applications by allowing illumination as well as data transmission both of which not affected on each other. The transmitter comprises On-Off keying (OOK) modulation and LED to send data by flashing the light at a flicker-free frequency and speed undetectable to the human eye. In order to avoid flickering in lighting, the designated system should work above 200Hz. The receiver comprises photodiode and its amplification system followed by Bluetooth module to ensure its connectivity to a smart phone.PWM signals are modulated (Single carrier modulation technique) by the user data and the led driver drive the LED according to the modulated PWM signal.VLC is the peer to peer communication. Therefore, it is enables for several other applications such as home, office, airplane etc.

Keywords: Visible light communication, White light emitting diode, Modulation techniques, Led driver.