Patent ID: 8570933

Claim:
A method for self-interference suppression in a relay for wireless communication, wherein said relay is a part of a communication channel between a transmitter and a receiver in a wireless communication system, said relay being arranged for receiving a signal r(n) transmitted from said transmitter, and transmitting a self-interference suppressed transmit signal x r (n) to said receiver, said communication channel having a transmit channel, defined by a transmit channel matrix (H 1 ) between said transmitter and said relay, a receive channel, defined by a receive channel matrix (H 2 ) between said relay and said receiver, and a self-interference channel between an relay output and a relay input of said relay, the self-interference channel being defined by a self-interference channel matrix (H 0 ), the method comprising: receiving at the relay input of said relay a receive signal r(n) transmitted from said transmitter over said transmit channel; determining a receive suppression filter matrix W r , in said relay, based on said transmit channel matrix (H 1 ) and said self-interference channel matrix (H 0 ); determining a transmit suppression filter matrix W t , in said relay, based on said receive suppression filter matrix W r , said receive channel matrix (H 2 ), and said self-interference channel matrix (H 0 ); determining a self-interference suppressed transmit signal x r (n) by applying said receive suppression filter matrix W r , a relay amplification matrix G and said transmit suppression filter matrix W t , to said received signal r(n); and transmitting said self-interference suppressed transmit signal x r (n) from said relay over said receive channel to said receiver.