A signal analyzer includes a sampling unit, a filter unit coupled to the sampling unit, a computing unit coupled to the filter unit, and an output unit coupled to the computing unit. The sampling unit is operable to sample a time domain signal from a target system according to a predetermined sampling frequency to obtain a sampling signal. The filter unit is configured to perform filter processing upon the sampling signal so as to filter out harmonic frequency components from the sampling signal, thereby obtaining a fundamental frequency signal having a plurality of sample points. The computing unit is operable to compute a signal parameter set for each of temporally adjacent pairs of the sample points of the fundamental frequency signal. The output unit is configured to output information about dynamic behavior of the target system based upon the signal parameter sets computed by the computing unit.