QUALCOMM Incorporated
Self-interference cancellation for in-band full-duplex wireless communication

Abstract:

An in-band full-duplex transceiver includes a self-interference mixer for up-converting an adjusted digital baseband signal into an up-converted self-interference cancellation signal. The adjusted digital baseband signal has a phase opposite to a phase for a leakage signal from a leakage path for the transceiver. Similarly, the adjusted digital baseband signal has a magnitude matching a magnitude for the leakage signal. Given this phasing and magnitude for the up-converted self-interference signal, it substantially cancels the leakage signal when added with a received signal contaminated by the leakage signal.