DFT-based PSA channel estimation using linear prediction for OFDM systems with virtual carriers

This paper proposes an improved discrete Fourier transform-based and pilot-symbol-aided channel estimation (DFT-based PSA CE) for coherent orthogonal frequency division multiplexing (OFDM) systems. Conventional DFT-based PSA CE suffers from the dispersive distortion of an estimated channel impulse response (CIR) caused by virtual carriers. The proposed method estimates an equal-spaced channel frequency response (CFR) in a virtual carrier region by using forward and backward linear prediction (FBLP). Simulation results show that the proposed method outperforms the conventional one with slightly increased complexity and provides a performance similar to the frequency domain linear minimum mean square error (LMMSE) channel estimation with significantly reduced complexity.