Abstract: It is demonstrated that the finite discrete Fourier transform of the structural free vibrations can be considered just as the frequency response functions of the structure and its vibration modal parameters can be identified from them with general frequency-domain identification methods. In this way comes into being an ideal combination of both time-domain and frequency-domain modal identification techniques. It is proved to be correct and very convenient by identification tests for both simulated and actual structures.

Key words: modal ident ification, dynamic modeling, time - domain identificat ion, frequency- do mani ident ification