A method of channel estimation and a channel estimator for a multiple carrier radio transmission system is described. The method comprises receiving a signal comprising a symbol-carrier matrix, the symbol-carrier matrix comprising a pre-determined pattern of pilot symbols, and determining first channel estimates at pilot symbol positions of the pilot symbols in the symbol-carrier matrix. The method further comprises determining second channel estimates at intermediate positions of the symbol-carrier matrix, wherein the intermediate positions are separated from the pilot symbol positions of the pilot symbols by positions associated with non-determined channel estimates and determining third channel estimates at further positions of the symbol-carrier matrix.