Fast Fading Compensation Based on Weighted Channel Variance for TFI-OFDM

Orthogonal frequency division multiplexing (OFDM) systems have attracted attention as the fourth generation mobile communication systems. In OFDM systems, the impact of a fading is identified by using the channel estimation (CE). However, a large number of pilot symbols is required to identify an accurate channel state information (CSI) in the conventional OFDM systems. To reduce this problem, a time frequency interferometry (TFI) for OFDM has been proposed. Under the fast fading environment, since the channel is rapidly changed, many errors are occurred. Therefore, we have proposed the fast fading compensation method by using the decision direct and linear prediction methods. However, this method has several problems. To overcome these problems, in this paper, we propose the nonlinear prediction method based on the weighted channel variance.

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