Variable-sample-rate delayless frequency-adaptive digital filter for synchronized signal acquisition and sampling

In this paper, a hardware-based variable-sample-rate delayless frequency-adaptive cascaded digital filter is proposed. The open-loop frequency-adaptive and delayless property of a cascaded filter consisting of a median filter of length 3, a Blackman bandpass filter of length 30, and a predictive filter of length 25 is experimentally verified. Simulation results illustrating the filter's output response to input disturbances, in a synchronization signal acquisition application, are also presented.