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3.7 Numerical Analyses 287
To solve only for one
variable, specify the
variable as second
argument.
Display the simulation
result with BodePlot.
In[6]:= ACAnalysis[lowpasseqs, V$3, {f, 1., 1.*^6}]
Out[6]=
V$3 InterpolatingFunction1., 1. 10 6 ,
In[7]:= BodePlot[acsweep, {V$2[f]}, {f, 1., 1.*^6}]
Magnitude (dB)
0
-10
-20
-30
-40
-50
1.0E0 1.0E1 1.0E2 1.0E3 1.0E4 1.0E5 1.0E6
Frequency
Phase (deg)
0
-20
-40
-60
-80
1.0E0 1.0E1 1.0E2 1.0E3 1.0E4 1.0E5 1.0E6
Frequency
V$2[f]
Out[7]= Graphics
3.7.4 NoiseAnalysis
NoiseAnalysis[dae, invar, outvar, {f, fstart, fstop}]
computes the output noise and the equivalent input noise
for a linear DAEObject dae where the input signal is
specified by invar and the output by outvar
Command structure of NoiseAnalysis.
This functions allows for carrying out a numerical noise analysis. The output noise and the equivalent
input noise are computed from a linear DAEObject dae, where the parameter invar denotes the input
and the variable outvar denotes the output, respectively. Use GetParameters to get a valid list of
input symbols and GetVariables for a list of valid output symbols.
NoiseAnalysis returns the result according to the Analog Insydes numerical data format (see
Section 3.7.1) for the output noise (denoted by the symbol OutputNoise), the equivalent input
noise (denoted by the symbol InputNoise), the output variable outvar, and each noise source. The
computed values for the noise sources are given in A Hz and V Hz, input and output noise in
A Hz and V Hz, respectively.
The result of the numerical noise analysis can be displayed with Analog Insydes graphics functions
such as BodePlot (Section 3.9.1).
The DAEObject dae must be set up symbolically (use ElementValues −> Symbolic during equation
setup). Note that at least all sources (noise sources and the one small-signal input source invar)