Performance degradation due to Inter-Carrier Interference (ICI) resulted from channel Doppler effects is significant for Orthogonal Frequency Division Multiplexing (OFDM) when used in mobile communication systems.In this paper
the mechanism of OFDM ICI caused by Doppler effects is discussed.Based on the I/O relationship of channel output Doppler-spread function
a 3-dimensional graphic form for visualizing the received OFDM signal structure and a simple method for calculating ICI levels of arbitrary subcarrier in channels