Adaptive time interpolator for OFDM systems in time-variant channels

This paper introduces an adaptive time interpolator for orthogonal frequency division multiplexing (OFDM) systems in time-variant channels. The off-diagonals of the channel matrix, which represent the inter-carrier interference (ICI) coefficients, are estimated by approximating the channel over few successive symbols making use of Taylor and Lagrange polynomial interpolation. The interpolation degree is adapted according to the estimated Doppler spread aiming at minimizing the bit error rate (BER) performance as a subject to the processing delay.