1. A system, comprising: a separation block configured to separate a signal into a reference signal component and a target signal component; a digital signal processor (DSP) configured to: filter the reference signal component according to a plurality of filter coefficients to provide an output signal that is substantially similar to the target signal component; and adjust the plurality of filter coefficients to drive a feedback signal to a predetermined level; and a combiner configured to subtract the output signal and the target signal component to provide the feedback signal.