Patent ID: 6907093

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 comprising the steps of: generating at said first device a modulated near signal; transmitting said modulated near signal from said first device to said relay station; receiving at said first device a composite signal from said relay station, said composite signal containing a relayed version of said modulated near signal and a relayed version of a modulated far signal transmitted from said second device; providing said composite signal in a representation as a first interface signal to a canceler module of said first device; providing a representation of said modulated near signal as a second interface signal to said canceler module, said second interface signal being of a frequency centered at or near a second interface frequency not at baseband; canceling at said canceler module a portion of said relayed version of said modulated near signal from said representation of said composite signal using said second interface signal to a produce a cancellation-processed signal; outputting said cancellation-processed signal as a third interface signal from said canceler module; and wherein said canceling step includes: applying a time delay and phase rotation to a representation of said second interface signal to obtain a time-delayed and phase-rotated local near signal; correlating said time-delayed and phase-rotated local near signal with at least a representation of said first interface signal to obtain correction signals for said time-delayed and phase-rotated local near signal; adaptively filtering said time-delayed and phase-rotated local near signal to produce a filtered signal; and applying said filtered signal with said at least said representation of said composite signal to yield said cancellation-processed signal.