Improved Channel Estimation Algorithm for OFDM System over Slow Fading Rayleigh Channel

Orthogonal Frequency Division Multiplexing (OFDM) is being used by the modern communication systems due to the increase in demand for high throughput wireless communication systems. OFDM has highly efficient spectrum usage and robustness to multipath fading channel impairments. The focus of the paper is to improve Discrete Fourier Transform (DFT)based channel estimator designed over a slow fading Rayleigh channel. In conventional DFT based channel estimator, the channel impulse response was calculated using Least Square (LS) estimator. In the proposed algorithm for the channel impulse response estimation, the MMSE estimator is employed instead of LS estimator. The comparison shows that the performance of the MMSE estimator is optimum than the LS estimator with the sense of MSE (mean square error). Therefore, it is preferred over LS estimator. The simulation results revealed better results for the proposed channel estimation scheme than the DFT-based estimator.