1. A method for signal processing, comprising: receiving a signal modulated with data, the signal including noise from a wireless medium; providing a first matrix of dimension N×N, wherein the first matrix comprises discrete Fourier transform (DFT) coefficients of the signal; generating, from the first matrix, a second matrix of dimension M×M, wherein M<N; processing the second matrix to generate K eigenvalues and K eigenvectors, wherein K<M; generating a rank-K matrix using the generated K eigenvalues and K eigenvectors, said rank-K matrix being an approximation of the first matrix, wherein the rank-K matrix comprises DFT coefficients related to the signal with reduced noise; and recovering the data from the reduced-noise signal.