Adaptive grouping MMSE channel estimation in OFDM-based wireless systems

In this paper, we design an minimum mean-square error (MMSE)-type channel estimation scheme in orthogonal frequency division multiplexing-based wireless systems. By using the averaged channel frequency response (CFR) of pilot symbols in a group as a representative CFR, the proposed MMSE channel estimator can reduce the mean-square error (MSE) of channel estimation by achieving the signal-to-noise ratio (SNR) gain without increasing the computational complexity compared to conventional MMSE channel estimator. The grouping size of pilot symbols is optimized to minimize the MSE according to the channel correlation characteristics. Finally, the performance of the proposed channel estimation scheme is verified by computer simulation.