A signal receiver processing circuit is for isolating a desired signal from analog input signal that is susceptible to variations in signal power, e.g. from a radio front end (12). The device has a variable gain amplifier (13) and an analog to digital converter (14) for providing a digital signal to a digital signal processor (15), the digital signal processor including a digital filter. The device has a control unit (16) for adjusting a filtering accuracy of the analog to digital converter (14) and/or the digital signal processor unit (15) in dependence of a signal quality of the input signal.