Patent ID: 8194763

Claim:
A method for decoding 2×2 space-time codes of a vector Y, in particular of the Golden Code type, the decoding method comprising a decoder for performing the following steps: a filtering of the minimum mean square error-generalized decision feedback equalizer (MMSE-GDFE) type is carried out by the decoder in order to obtain a vector Y F =RX+W, with Y F the vector Y filtered by means of a filter matrix F (“forward filter”), R a conventional matrix named “backward filter”, X the vector transmitted and W the complex noise matrix; a constellation recentring is carried out by the decoder so that the vector to be determined becomes Z, such that Z=Y F −2K M RΓS 0 =2K M RΓS+W, K M being the normalization constant for the constellation in question, F being the Golden Code, and S the vector of the information symbols; a step of permutation of the elements of the matrices Z, R and F is carried out by the decoder in order to obtain {tilde over (Z)}, {tilde over (R)} and {tilde over (Γ)} such that {tilde over (R)} H R is a matrix in the form of an X and the complex number “i” is moved from Γ to R; a step of lattice basis reduction is carried out by the decoder such that {tilde over (Z)}=2K M {tilde over (Ψ)}{tilde over (Γ)}S′+W with {tilde over (Ψ)}={tilde over (R)}.Δ α (x 1 , x 2 , x 3 , x 4 ) and S′=π α −1 (x 1 , x 2 , x 3 , x 4 ).S, π α (x 1 , x 2 , x 3 , x 4 ) being a basis change matrix, π α (x 1 , x 2 , x 3 , x 4 ) is the matrix associated with Δ α (x 1 , x 2 , x 3 , x 4 ) which is a matrix in which the determinant module is equal to 1 and defined such that Δ α H Δ α is a matrix in the form of an X; and the zero forcing-decision feedback equalizer (ZF-DFE) decoding algorithm is applied by the decoder, in which among the four elements of two layers are identified, each layer comprising the two elements of the diagonal or anti-diagonal of {tilde over (Z)}; the DFE algorithm is applied layer by layer and the ZF algorithm within each of the layers.