VLC BASED INDOOR BLIND NAVIGATION SYSTEM

摘要

The Visible Light Communication (VLC) has become promising for various wireless applications. VLC- assisted indoor positioning is aimed at providing guidance to the blind people due to its unique advantage of electromagnetic interference immunity and accuracy, instead of conventional wireless positioning system using radio frequency equipment. The blind people could use the system to locate the objects or places in an unknown indoor environment. A number of fixed transmitters and a moving receiver together contribute to the positioning process. The transmitter is fixed in the object or place which the blind people have to identify. A transmitter section consisting of a mode switch, microcontroller and Li-Fi transmitter, i.e., a number of photodiodes (PDs) that emits visible light continuously, send the predefined information of the object or place when the moving receiver section consisting of a Li-Fi reader, microcontroller, speaker come in line of sight with the transmitter. The blind people carry the receiver. When the transmitter and the receiver syncs, the information fed in the Tx microcontroller is delivered to the reader which in turn stimulates the Rx microcontroller to trigger the proper voice output by switching on the voice recorded circuit, and send it through the speaker thereby helping the blind people to identify the object or place ahead of them.