System and method for analyzing an input signal acquired from a physical system with a rotating element. A tachometer signal is received comprising rotation speed information for the rotating element. A time sequence is determined using the tachometer signal, comprising time values for the rotating element at substantially equal angle increments, e.g., by edge detection software or timer/counter. A software-based first digital interpolation filter, e.g., a Cascade-Integrator-Comb filter, is applied to the time sequence, generating a modified time sequence. A digitized data signal is received comprising data for the rotating element at substantially equal time increments. A second software-based digital interpolation filter is applied to the data signal, generating a modified data signal which is re-sampled using the modified time sequence to generate an angle domain data signal, comprising data signal values at substantially equal angle increments, where the angle domain data signal is usable to analyze the physical system.