A novel protocol design in hybrid networks of Visible Light Communication and OFDMA system

In recent years, Visible Light Communication (VLC)has emerged as a complementary technique to overcome the limitations of crowded radio frequency(RF) spectrum. Its superior characteristics include unlicensed wide bandwidth, high security and dual-use nature. It can transmit 4Mb/s in short distance. However VLC using illumination source is naturally suited to broadcast applications, it can also be used for full duplex communication but it resulted in instability of the system as it cannot operate without optical wireless localization technology, hence a hybrid network has been designed in which OFDMA is used for uplink transmission and VLC is used for downlink transmission. In order to demonstrate this a protocol has been proposed by combining the horizontal and vertical handover mechanisms for mobile terminal to resolve user mobility among different VLC hotspots and orthogonal frequency division multiple access(OFDMA).