Abstract—OFDM based wireless systems are spectrally efficient but they are very sensitive to Doppler shift. The high mobility causes the channel to vary fast and the rapid variation of the channel can induce Inter Carrier Interference (ICI). ICI due to fast fading channel is more difficult to handle and it causes loss of orthogonality between the sub carriers. This kind of ICI can be easily reduced by increasing the sub carrier bandwidth. In this paper we proposed an Adaptive OFDM system which will use Variable Sub carrier Bandwidth (VSB) and Variable Bit Loading (VBL) based on the Doppler velocity to minimize the effect of ICI. We investigate the performance of such Adaptive OFDM system with conventional OFDM system based on throughput.

Index Terms—Adaptive OFDM, ICI, VSB-VBL Technique

K.V.N.Kavitha, Senior Assistant professor is now with the School of Electrical Sciences, Vellore Institute of Technology, Vellore, India. (e-mail: kvnkavitha@yahoo.co.in).
K.Vinoth Babu, Assistant Professor is now with the School of Electrical Sciences, Vellore Institute of Technology, Vellore, India. (e-mail: vinothbabu.k@vit.ac.in).

Cite: K.V.N. Kavitha and K. Vinoth Babu, "Adaptive OFDM for High Mobility Computer Application," International
Journal of Computer and Electrical Engineering vol. 2, no. 1, pp. 59-62, 2010.