PSD to Time Series

PSD to Time Series synthesizes one real, zero-mean time-history channel whose expected one-sided PSD follows an input PSD curve.

Input and output

• Input: one one-dimensional PSD histogram curve.
• Output: one synthesized time-series channel.

The input frequency values must be finite, non-negative, and strictly increasing. The PSD values must be finite and non-negative, with at least one positive value.

Main parameters

• Sampling Rate: output sampling rate; must be positive.
• Duration: output duration; must be positive.
• PSD Interpolation: Log-Log or Linear.
• Channel Name and Channel No.: output channel identification.
• Output Unit: Auto derives common engineering units from the PSD unit; Manual requires an explicit output unit.

The product of sampling rate and duration must produce at least two samples. One run is limited to 20,000,000 samples.

Usage notes

• Frequencies outside the input PSD range contribute zero energy to the synthesized signal.
• When log-log interpolation cannot be applied (for example, non-positive values), the calculation falls back to linear interpolation.
• The random synthesis is non-repeatable unless a workflow supplies a random seed. Check the resulting PSD or time history with a visualization module before using it in a fatigue calculation.