The calculation of PSD has many specialities. Simple FFT transformation solves the problem (theoretically), but in practics there are more problems.
E.g.: time signal has finite length, while FFT decompose signal into a number of SIN/COS functions which are infinite, and to make it the time...
Adina may be pre- and postprocessed by MSC.Patran(http://www.adina.com/cadlink/patran.shtml).
To use MSC.Patran with ADINA you should purchase ADINA, MSC.Patran and so called "ADINA preference for MSC.Patran". The last one i think may be purchased from ADINA as well as MSC - contact...
There is possibility of adjusting FEM-model parameters (shell thickness, masses, etc.) with experimental vibration charakteristics (e.g. egenvalues) in some special packages.
You must build and analize the FEM-model prior such an adjusting . Then the program changes properties of the FEM-model...