Patent ID: 7551547

Claim:
A method of channel estimation for a multi-carrier modulation of a plurality of sub-carriers, the method comprising: transforming a transmitted symbol matrix based on a non-identity transformation, the non-identity transformation based on a finite spread of a channel impulse response in a time domain and usable to improve accuracy of channel estimation in a frequency domain, wherein the non-identity transformation is based on a matrix from a singular value decomposition of a Discrete Fourier Transform (DFT) matrix, wherein the DFT matrix is N×L-dimensional, wherein L is a length of the channel impulse response and N is a number of sub-carriers, and wherein the DFT matrix has elements F ⁢ i , ⁢ k = ⅇ - j2π ⁢ ( i ⁢ - ⁢ N ⁢ 2 ) ⁢ ⁢ k ⁢ N , wherein i is a row index from 0 to N−1, k is a column index from 0 to L−1, and j is the square root of −1; transforming a received symbol vector based on the non-identity transformation; using a channel estimation method to determine a transformed channel vector based on the transformed transmitted symbol matrix and the transformed received symbol vector; suppressing one or more elements in the transformed channel vector to at or about zero to form a suppressed transformed channel vector; and inverse transforming the suppressed transformed channel vector into an estimated channel vector based on the non-identity transformation.