Patent ID: 8488690

Claim:
A method of channel estimation for a multiple carrier radio transmission system, comprising: receiving a signal comprising a symbol-carrier matrix, the symbol-carrier matrix comprising a pre-determined pattern of pilot symbols; determining first channel estimates at pilot symbol positions of the pilot symbols in the symbol-carrier matrix; 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, wherein determining the second channel estimates is performed by one or more of one-dimensional interpolation and two-dimensional interpolation from the first channel estimates, and wherein interpolation coefficients are determined for interpolations by 1D Wiener filtering in the time direction and the frequency direction, wherein the interpolation coefficients for the interpolation in the time direction are determined depending on a maximum Doppler bandwidth f max according to the following formulas: w t ( l ) T =[w t,1 ( l ), . . . , w t,N t ( l )]= r t ( l ) T R t −1 wherein [ r t ( l )] i =si (2 πf max T S ( l−i )) wherein si denotes the sinc function, T s denotes the symbol duration and the index i indicates a time taken from a set T of times associated with the OFDM symbols used for interpolation, wherein the set T includes N t times and the index i runs from 1 to N t , and the parameter i accounts for the fact that 1D Wiener filtering amounts to a sliding window operation along the time axis, and [ R t ] i,j =si (2 πf max T S ( i−j ))+ N 0 /E S δ( i−j ), wherein the indices i and j run from 1 to N t , respectively, N 0 denotes the variance of the additive white Gaussian noise, and E s denotes the energy per modulated symbol, and the interpolation coefficients for the interpolation in frequency direction are determined depending on a cyclic prefix length τ max according to the following formulas: w f ( n ) T =[w f,1 ( n ), . . . , w f,N f ( n )]= r f ( n ) T R f −1 wherein [ r f ( n )] i =si (2πτ max ΔF ( n−i )), wherein the index i indicated a frequencies taken from a set F of frequencies associated with the pilots used for interpolation, the set F includes Nf frequencies and the index i runs from 1 to Nf, the parameter ΔF denotes the subcarrier spacing, and the parameter n accounts for the fact that 1D Wiener filtering amounts to a sliding window operation along the frequency axis, and [ R f ] i,j =si (2πτ max ΔF ( i−j ))+ N 0 /E S δ( i−j ).