REJECTION OF TRANSMISSION SIGNAL LEAKAGE IN WIRELESS COMMUNICATION DEVICE

摘要

PROBLEM TO BE SOLVED: To reduce adverse effects of second order distortion and cross-modulation distortion of transmission signal leakage from a transmitter via a duplexer in a full-duplex, wireless communication system.SOLUTION: An adaptive filter 40A includes an estimator circuit that generates a transmission leakage signal estimate e(t). A summer 62 subtracts the estimate e(t) from a received signal x(t) to cancel transmission leakage and produce an output signal y(t). The estimator circuit generates the transmission leakage signal estimate e(t) on the basis of a reference signal r(t) and feedback from the output signal y(t). The reference signal r(t) approximates a carrier signal used to generate a transmission signal in a transmitter. The reference signal r(t) may be provided by the same oscillator as an oscillator 42 used to produce a transmission carrier signal.