Load Pull Simulation Using ADS教程.ppt

Andy HowardApplications Engineer28 May, 2002
Load Pull Simulation Using ADS
Outline
Overview
Specifying and generating desired load reflection coefficients
Assigning arbitrary reflection coefficients at the harmonic freqs.
Biasing the device and running a simulation
Calculating desired responses (delivered power, PAE, etc.)
Generating contour lines
Load Pull Simulation Using ADS
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Load pull simulation varies the load reflection coefficient presented to a device...
Vary load
reflection
coefficient
Load Pull Simulation Using ADS
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…to find the optimal value to maximize power or PAE, etc.
Load Pull Simulation Using ADS
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Specify the load reflection coefficients
Simulation set up is
complicated, but
region is sampled
more uniformly
Simulation set up
is trivial
Load Pull Simulation Using ADS
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Sweeping rho over a circular region
Specify circular region, via s11_rho and s11_center
variables
This is just a
static figure. It
does not get updated
nor correspond
to the values in the
equations.
Radius of circle
Center of circle
Load Pull Simulation Using ADS
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Use ReflectionCoefUtility data display to help set s11_center and s11_rho
The circle center and
radius are updated when
you move either or both
of the markers
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Two variables are swept to generate the points within the desired circle
These initialize the
swept variables
indexs11 is the reflection
coefficient
Will explain Start
and Stop equations
later
Load Pull Simulation Using ADS
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More on the swept variables
Variable “imag_indexs11” is
the y-axis value of simulated
reflection coefficient.
Variable “real_indexs11” is
the x-axis value. The
imag_indexs11 variable is
stepped uniformly, whereas
real_indexs11 is stepped
non-uniformly.
Each point is a data pair:
(real_indexs11, imag_indexs11)
m3 is at approximately:
(-, )
Load Pull Simulation Using ADS
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Sweep limits for “imag_indexs11”
Arrow points to s11_center
imag(s11_cen