The main aspects of the complex amplitude method were developed for analyzing the modulated oscillations in radio engineering systems. Such signals representing the oscillations of the carrier frequency ω0 modulated by a relatively low-frequency signal Ωmax are characterized by the relationship Ωmax ≪ ω0. Most generally vibroseismic signals do not meet this requirement though with some stipulations the complex amplitude method applied in many cases yields correct results and makes it possible to use the tools developed for radio engineering. It is shown that the method is promising, and application results of some algorithms are presented by an example of real vibroseismic signal processing.