Patent ID: 7848748

Claim:
A method of using one or more transmitters and/or one or more parameters associated with a transmitter by using a reception station having a device suitable for measuring over time a set of K parameters dependent on the transmitting associated with vectors {circumflex over (η)} k representative of the transmitters for 1<k<K comprising the steps of: extracting the parameter or parameters consisting in grouping together by transmitter the parameters which are associated therewith by means of a technique of independent component analysis, wherein the step of associating the parameters for each transmitter M comprises at least the following steps: Step No. 1 transforming the vectors {circumflex over (η)} k representative of the set of the K parameters for the M transmitters into vectors f({circumflex over (n)} k ) by using a bijective function {tilde over (f)}( ) and where the 1 st component of f({circumflex over (η)} k ) being equal to 1, Step No. 2 determining a covariance matrix {circumflex over (R)} xx the vectors f({circumflex over (n)} k ) and decomposing it into eigenelements, so as to obtain its eigenvalues, where {circumflex over (R)} xx is a matrix related to the vector space of the M signatures f(η m ){circle around (×)}f(η m ) of the transmitters, Step No. 3 calculating the rank M of the matrix {circumflex over (R)} xx its eigenvalues found in step 2, Step No. 4 calculating a square root of {circumflex over (R)} xx its M dominant eigenelements: {circumflex over (R)} xx 1/2 =E s Λ s 1/2 where E s corresponds to the eigenvectors and Λ s to the M largest eigenvalues, Step No. 5 deducing from {circumflex over (R)} xx 1/2 the matrices Γ n according to R ^ xx 1 / 2 = [ Γ 1 ⋮ Γ N ] = B ⁢ ⁢ U H with Γ n =AΦ n U H and from the Γ n calculating Ψ ij according to Ψ ij =Γ i # Γ j =UΨ i −1 Ψ j U H for (1≦i≦N and j<i), where the columns of each matrix Γ n define the same space vector as the signatures f(η m ) of the M transmitters, Step No. 6 identifying unitary matrix U by joint diagonalization of the Ψ ij for (1≦i≦N and j<i), Step No. 7 determining the vectors f(η m ) from the columns b m of the matrix {circumflex over (R)} xx 1/2 U where U is the unitary matrix: Transformation of column b m into the matrix B m according to B m =[b m1 . . . b mN ]=f(η m )f(η m ) T √{square root over (ρ m )} and extraction of this matrix from the singular vector e m associated with the largest singular value so as to perform f(η m )=e m /e m (1) with e m (1) the component of the vector e m , and Step No. 8 applying the inverse transform of the function {tilde over (f)}( ) so as to deduce therefrom the vectors η m .