Patent ID: 7349505

Claim:
A method for providing self-interference cancellation in two-way relayed electromagnetic communication between a first device and a second device through a relay station, the first device being capable of transmitting a modulated near signal and receiving a composite signal containing a relayed version of the modulated near signal a relayed version of a modulated far signal transmitted from the second device, the method comprising the steps of: retrofitting existing equipment at the first device by adding a canceler module, wherein the existing equipment comprises a transmitter system and a receiver system; providing a version of the modulated near signal as a first non-baseband interface signal from the transmitter system to the canceler module; providing a version of the composite signal as a second non-baseband interface signal from the receiver system to the canceler module; at the canceler module, generating a cancellation signal corresponding to the relayed version of the modulated near signal, using the first non-baseband interface signal and the second non-baseband interface signal; at the canceler module, applying the cancellation signal to a version of the second non-baseband interface signal, to produce a cancellation-processed signal as a third non-baseband interface signal from the canceler module; providing the cancellation-processed signal to the receiver system; and wherein the canceler module generates a time-delayed and phase-rotated signal in producing the cancellation signal.