Model noise using current or voltage noise source in RF systems




Use the Noise block to model noise as a current or voltage source for blocks other than Amplifier and Mixer blocks. When you use a Noise to simulate noise in an RF model, also select the Simulate noise check box in the Configuration block. Otherwise, the model simulates without noise. The Noise block does not depend on the Temperature parameter in the Configuration.

Dialog Box and Parameters

Source type

Specify the noise type as Ideal Voltage or Ideal Current. The default is Ideal Voltage.

Noise distribution

Specify the noise distribution type as White or Piece-wise linear. The default is White.

Noise power spectral density

Specify the single-sided noise power spectral distribution (PSD). The default value of this parameter is 0.

When Noise distribution is set to:

  • White, spectral density is a single non-negative value.

  • Piece-wise linear, spectral density is a vector of values [pi].

When Source type is set to:

  • Ideal voltage, spectral density units are V2/Hz.

  • Ideal Current, spectral density units are A2/Hz.


This parameter appears only when Noise distribution is set to Piece-wise linear.

Parameter values are specified as a vector of non-negative frequencies [fi] with the same length as the vector of power spectral densities [pi]. The pairs, (fi,pi), define an arbitrary piece-wise linear noise distribution. The default value of this parameter is 0 Hz.


 Explicitly Simulate Resistor Thermal Noise


Motchenbacher, C.D. and J.A. Connelly. Low Noise Electronic System Design. New York: John Wiley & Sons, 1993.

See Also

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