Decision Directed Iterative Equalization of OFDM Symbols Using Non-Uniform Interpolation

In this work, a decision-directed iterative channel estimation scheme is proposed for pilot symbol assisted OFDM systems. The technique is based on non-uniform interpolation of irregularly spaced "pseudo-pilot" tones, which are generated by utilizing the soft outputs of a FEC decoder. The proposed approach is tested in simulated time and frequency-selective fading channels and results are presented. It is shown that the channel estimation technique based on the non-uniform interpolation of the extended pilots performs better than uniform interpolation at high SNR values.