Disclosed is a method for transmitting from a transmitter device having M transmit antennas to a receiver device having N+C receive antennas, where M, N, and C are integers greater than or equal to 1. In one embodiment, the method comprises a process of spatial frequency multiplexing a block of N data symbols D1, D2, . . . , DN resulting in a block of N payload spatial symbols Su,1, Su,2, . . . , Su,N, using an inverse discrete Fourier transform (IDFT), a process of adding C redundancy spatial symbols to the block of N payload spatial symbols, resulting in a block of N+C spatial symbols S1, S2, . . . , SN+C, and a process of precoding the block of N+C spatial symbols S1, S2, . . . , SN+C with the help of a focusing matrix of dimensions M×(N+C), delivering M precoded spatial symbols X1, X2, . . . , XM, each precoded spatial symbol being transmitted over a distinct transmit antenna.