Low-Complexity Channel Estimation for OFDM Systems with Guard Subcarriers

In the actual orthogonal frequency division multiplexing (OFDM) systems since guard subcarriers are not used for transmission, some conventional channel estimators are not applicable. This paper, based on the criteria of least square (LS), proposes a novel channel estimation method for OFDM systems with guard subcarriers. The discrete Fourier transform (DFT)-based channel estimator can cause the aliasing error and high-frequency distortion when there exist guard subcarriers, but our proposed method can mitigate this problem and attain the better estimation performance with fewer pilots. Furthermore, compared with the conventional LS estimator, the proposed method has close performance but lower complexity and can be realized in the actual OFDM systems. Analyses and simulations demonstrate the effectiveness of the proposed approach.