Patent ID: 7742536

Claim:
A method for transmitting data through a MIMO-OFDM system having a transmitter and a receiver that communicate through a channel, wherein the transmitter comprises M T transmitter units TU 0 . . . TU M T −1 and the receiver comprises M R receiver units RU 0 . . . RU M R −1 , said method comprising the steps of a) feeding a sequence of original symbols to said transmitter, each original symbol comprising N>1 vectors c k with k=0 . . . N−1, wherein each vector c k has M T complex-valued coordinates (c 0 ) k . . . (c M T −1 ) k to be fed to the transmitter units TU 0 . . . TU M R −1 , b) OFDM-modulating said original symbols in said transmitter units and transmitting them to said receiver units, c) receiving, by said receiver units, said transmitted symbols distorted by the channel and decoding them into received symbols, wherein each received symbol comprises N vectors r k with k=0 . . . N−1, wherein each vector r k has M R complex-valued coordinates (r 0 ) k . . . (r M R −1 ) k , wherein, at least in approximation, r k =√{square root over ( E s )}· H ( s k ) c k +w k , with √{square root over (E s )} being a constant, s k =exp(−j2πk/N), j being the imaginary unit, H ⁡ ( s k ) = ∑ l = 0 L - 1 ⁢ H l ⁢ s k l , L an integer smaller than N, H l being an M R ×M T matrix having coefficients (H ij ) l describing the value at discrete-time delay l of the discrete-time impulse response of the channel between transmitter unit TU j and receiver unit RU i , and w k being a noise vector, d) said method further comprising the step of carrying out at least one computation of a function f(H(s k )) for k=0 . . . N−1 on said matrices H(s k ), which function f can be expressed as f(H(s k ))=f NP (f P 0 (H(s k )), . . . f P J−1 (H(s k ))) with J≧1 and scalar-, vector- or matrix-valued polynomial functions f P 0 (H(s k )), . . . f P J−1 (H(s k )) that can be expressed as f P i ⁡ ( H ⁡ ( s k ) ) = ∑ l = 0 N - 1 ⁢ A l i ⁢ s k l with coefficients A l i wherein a number Q i of said coefficients A l i are arbitrary functions A l i =g l i ( H 0 , . . . H L−1 ) of the matrices H 0 , . . . , H L−1 and a number N−Q i said coefficients A l i are zero, with 1≦Q i <N e) said method further comprising the step of carrying out at least one computation of a said function f P i (H(s k )) using the steps comprising step A) determining from known H(s k ), for at least some of said polynomial functions f P i (H(s k )), a number of V i ≧Q i values of said function f P i (s k ) at a set of s k with k∈Ω i and |Ω i |=V i ≧Q i , and step B) determining, for at least some of said polynomial functions f P i (H(s k )), at least one value f P i (H(s k )) for an s k with k∉Ω i by interpolation of the values of said function f P i (H(s k )) obtained in step A).