MMSE Noise Power and SNR Estimation for OFDM Systems

This paper proposes a minimum mean-square error (MMSE) filtering technique to estimate the noise power that takes into account the variation of the noise statistics across the orthogonal frequency division multiplexing (OFDM) sub-carrier index as well as across OFDM symbols. The proposed method provides many local estimates that allow tracking of the variation of the noise statistics in frequency and time. The MMSE filter coefficients are obtained from the mean-squared-error (MSE) expression, which can be calculated using the noise statistics. Evaluation of the performance with computer simulations shows that the proposed method tracks the local statistics of the noise more efficiently than conventional methods.