Patent ID: 8711959

Claim:
A frequency offset estimation method of an Orthogonal Frequency Division Multiplexing (OFDM) system performed by a communication signal receiver, comprising: receiving a reception signal; setting a specific initial frequency offset corresponding to the reception signal; and calculating a log-likelihood function based on a Complex Isotropic Symmetric a Stable (CISαS) probability density function obtained by modeling non-Gaussian noise included in the reception signal and estimating an optimum frequency offset based on the log-likelihood function and the initial frequency offset through a Maximum Likelihood Estimator (MLE), wherein the log-likelihood function is represented by Equation below; Λ ⁡ ( ɛ ~ ) = ∑ k = 0 N / 2 - 1 ⁢ log ⁢ {  r ⁡ ( k + N / 2 ) - r ⁡ ( k ) ⁢ ⅇ j ⁢ ⁢ π ⁢ ⁢ ɛ ~  2 + 4 ⁢ ⁢ γ 2 } wherein N indicates a number of samples of the reception signal, r(k) indicates a k th sample of the reception signal, γ indicates a degree of spreading of noise, and {tilde over (ε)} indicates a candidate value of the frequency offset.