MATLAB: Do I receive the type cast warning for the seed parameter of the Band-Limited White Noise block in Simulink

simulink

I am using a Band-Limited White Noise source block from the Simulink->Sources library in my model, for which I am using the "clock" variable to generate a random number for the seed parameter. When I update my diagram I get the following warning:

 Warning: Parameter Seed of 'untitled1/Band-Limited White Noise/White Noise' is being cast from data type 'double' to the data type 'uint32'. Downcasts and signed/unsigned mismatches of tunable parameter expressions are not recommended in order to ensure consistent behavior between Simulink and the Real-Time Workshop.

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The Band-Limited White Noise block expects a double type for the seed, that can convert to a uint32 unambigiously. To prevent this warning, use the FLOOR function around the function currently used to generate the seed parameter.

Related Solutions

MATLAB: How to generate band-limited Gaussian white noise?

You cannot generate band-limited "white" Gaussian noise. "White" noise means that the power spectral density is flat, which contradicts the notion of a passband.

You can generate band-limited Gaussian noise. I'm not sure what you mean by "...signal ranging from 0 to 3 with a frequency of 0-6Hz", so I'll assume that you want a passband of 0 to 6 Hz. You did not tell us your sampling frequency, I'll assume 100 Hz.

      Fs = 100;
      d = fdesign.lowpass('Fp,Fst,Ap,Ast',6,10,0.5,40,Fs);
      B = design(d);
      % create white Gaussian noise the length of your signal
      x = randn(1000,1);
      % create the band-limited Gaussian noise
      y = filter(B,x);

The output, y, is a band-limited Gaussian noise with a passband of 0 to 6 Hz.

MATLAB: Relationship between noise power in a Band-Limited White Noise block VS Variance in a Random Number block

You may want to look at the Algorithm section of the following doc page

https://www.mathworks.com/help/simulink/slref/bandlimitedwhitenoise.html

Basically the variance can be considered as 0.1/(1/0.001) which equals 100.

HTH

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Related Solutions

MATLAB: How to generate band-limited Gaussian white noise?

MATLAB: Relationship between noise power in a Band-Limited White Noise block VS Variance in a Random Number block

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