How can I model noise to add stochastic behaviour to a transient simulation?

Dynamic Simulation

In the attached example a random signal is generated using the sample and hold noise generator (ElmNoise) within a DSL model. The generated random signal is defined to change every 1/Frequency seconds. The random signal has a total power output defined by "Spectral power density" parameter. The probability distribution may be selected either to be uniform or Gaussian.

In the example the following objects are connected: 1. a sample and hold generator; 2. a noise test block diagram which performs, 2a. an amplification of the random signal, 2b. a power of two and 2c. a first order lag; 3. a test frame which connects the noise generator to the noise test block and which connects the lagged and amplified noise to FFT analyzers.

The example shows the time domain signals of the noise test block (amplified, squared and lagged signals), and the FFT diagram shows the FFT results. The power spectrum of the sample and hold noise signal is also shown in the example, where the output of the FFT blocks show the spectrum of the sample and hold noise and of the output of the first order lag filter.