Time-reversal method of pre-equalizing a data signal

A device for pre-equalizing a data signal for a source communicating entity having a set of source antennas, said source communicating entity being adapted to transmit said signal, using frequency-division duplexing, to a destination communicating entity having a set of destination antennas, said device comprising means for:

• receiving a pulse transmitted by a destination antenna;
• transmitting the received pulse to the destination communicating entity via a source antenna;
• receiving a time-reversed combined impulse response representing successive passage of said transmitted pulse through a first propagation channel between the destination antenna and a reference antenna of the set of source antennas and a second propagation channel between the source antenna and the destination antenna;
• determining coefficients for pre-equalizing the data signal on the basis of a combination of a set of received time-reversed combined impulse responses;
• the transmission and reception means being used iteratively for at least some of the destination antennas and at least some of the source antennas.

A device for pre-equalizing a data signal for a destination communicating entity, comprising a set of destination antennas, said destination communicating entity being adapted to receive said data signal transmitted, using frequency-division duplexing, by a source communicating entity comprising a set of source antennas, said device further comprising means for:

• transmission of a pulse to the source communicating entity by a destination antenna;
• receiving a combined impulse response representing successive passage of said pulse through a first propagation channel between the destination antenna and a reference antenna of the set of source antennas and a second propagation channel between a source antenna and the destination antenna;
• time reversing the combined impulse response;
• transmitting said time-reversed combined impulse response;
• the transmission, reception and time reversing means being employed iteratively for at least some of the destination antennas and at least some of the source antennas.