RADIO FREQUENCY TRANSMITTER NOISE CANCELLATION

摘要

PROBLEM TO BE SOLVED: To provide a low-power and reduced-size RF noise cancellation circuit that is able to cost efficiently minimize transmitter noise leakage in received signals without having its adaptation rate reduced by external blockers.SOLUTION: Transmitter noise cancellation may be applied on a channel by channel basis to active channels of an incoming radio frequency signal received at a receiver. A noise cancellation filter may be provided for each active channel in a predetermined signal band. Applying noise cancellation on a per active channel basis instead of to the entire receive band may substantially reduce the filtering requirement and number of filter coefficients or taps to save power and reduce manufacturing costs. Channelized transmitter noise cancellers, multi transmitter-receiver cross coupling cancellers, and hybrid full signal band and channelized transmitter noise cancellers are also provided.