An improved DFT-based channel estimation algorithm for MIMO-OFDM systems

In this paper, we present an improved DFT-based channel estimation method. The conventional discrete Fourier transform(DFT)-based approach will cause energy leakage in multipath channel with non-sample-spaced time delays. The improved method uses symmetric property to extend the LS estimate in frequency domain, and calculates the changing rate of the leakage energy, and selects useful paths by the changing rate. The computer simulation results show the improved method can reduce the leakage energy efficiently, and the performance of the improved channel estimation method is better than the LS and conventional DFT algorithm.