1. A method of estimating an Orthogonal Frequency Division Multiplex (OFDM) channel comprising: estimating a channel matrix using a basis expansion model (BEM); reducing a dimension of a coefficients matrix using a sub-space tracking algorithm; estimating each coefficient in the coefficients matrix using an iterative conjugate gradient algorithm, wherein a number of iterations performed is less than a number of variables to be solved; estimating a transmitted symbol based an estimated coefficient and a received symbol.