Wireless transmission using an adaptive transmit antenna array

A transmitter for closed loop wireless communication of signals comprising an adaptive transmit antenna array of size N, finite impulse response filter means for producing a plurality M of multi-path copies of the signals to be transmitted by said transmit antenna array with delays and weights that are functions of the multi-path transmission channel characteristics (H) from said transmit antenna array to a receive antenna array and for combining the copied signals before transmission by the transmit antenna array, the transmitter comprising:

• means for setting said weights substantially equal to a vector w, which is a concatenation of vectors w1, w2, . . . wN, where wi=(wi,1, wi,2, . . . , wi,M)t represents the coefficients of the FIR filter applied on transmit antenna #i and M is the number of elementary time intervals in the FIR filter delay scheme,
• means for calculating w to be substantially equal to the eigenvector corresponding to the largest eigenvalue of the matrix HHH, where H is the matrix of the equivalent channel seen by the symbol data and HH is the Hermitian transform of the matrix H, and
• means for propagating the multi-path signal components to each receiver element which are received with distinguishable delays according to the propagation path, and that the transmitted signals are suitable for reception by a receiver that combines the received signal components from each receive antenna element with delays and weights (u) that are respective functions of the multi-path transmission channels, wherein said delays and weights applied by said receiver are substantially equal to
• u
• =
• w
• H
• ⁢
• H
• H
• w
• H
• ⁢
• H
• H
• ⁢
• Hw
• .

A receiver comprising a receive antenna array having at least one receive antenna for reception by closed loop wireless communication of signals from a transmitter comprising an adaptive transmit antenna array of size N, in which a plurality M of copies of signals to be transmitted by said transmit antenna array are produced with delays and weights where the weights are functions of the multi-path transmission channel characteristics (H) from said transmit antenna array to a receive antenna array of a receiver and are combined before transmission by said transmit antenna array, said receiver comprises:

• receiving means for receiving the multi-path signal components having weights substantially equal to a vector w, which is a concatenation of vectors w1, w2, . . . wN, where wi=(wi,1, wi,2, . . . , wi,M)t represents the coefficients of the FIR filter applied on transmit antenna #i and M is the number of elementary time intervals in the FIR filter delay scheme, and with w calculated to be substantially equal to the eigenvector corresponding to the largest eigenvalue of the matrix HHH, where H is the matrix of the equivalent channel seen by the symbol data and HH is the Hermitian transform of the matrix H, said multi-path signal components propagated to each receiver element are received with distinguishable delays according to the propagation path, and
• combining means for combining the received signal components from each receive antenna element with delays and weights (u) that are respective functions of the multi-path transmission channels, wherein said delays and weights applied by said receiver are substantially equal to
• u
• =
• w
• H
• ⁢
• H
• H
• w
• H
• ⁢
• H
• H
• ⁢
• Hw
• .