Converts PSD units such as: g²/Hz, (m/s²)²/Hz and g/Sqr(Hz). If one is entered, the other two are automatically calculated.
Extract from the Help File
Power Spectral Density (PSD)
PSD is a method of describing the power contained within a defined bandwidth. The spectral components of a random waveform have the dimension of "spectral density". In particular the amplitude squared spectrum has units of energy per unit frequency. The process of analysing a random waveform measures the amplitude as an acceleration rms squared (gn rms)² in a given bandwidth, usually 1 Hz. Thus the unit g²/Hz, or more correctly written (gn rms)²/Hz describes the power in a one Hz bandwidth of a particular frequency. However, as this frequency may occur several times with different amplitudes over a long period, these amplitudes are added together to produce a total PSD at that given frequency.