A new DFT based Channel Estimation Method for OFDM Systems over Multipath Channels

摘要

Channel estimation is one of the most significant technologies in the orthogonal frequency division multiplexing (OFDM) system and its accuracy will influence the performance of the whole system directly. Among all kinds of channel estimation algorithms, the least square (LS) estimation and the linear minimum mean-squared error (LMMSE) estimation are the most classic ones. However, both the two estimator are not able to reach a compromise between accuracy and computational complexity. The discrete Fourier transform (DFT) -based channel estimation can get a better performance by a time domain processing. In this paper, we proposed an improved DFT based channel estimation which suppresses the noise by a new threshold setting method. The computer simulation results demonstrate that the proposed algorithm can reach accuracy close to the LMMSE algorithm and its computational complexity is much lower than the LMMSE estimator.