7-2018

RF & Wireless
This text or elements area can be
used to define the characteristics
of each element. In this case, elements
1, 4, 13, and 16 refer to
an antenna pattern called “Corner.”
The “Edge” elements are
referring to a different antenna
pattern and then the remaining
elements in the center that are
not defined as a number in the
figure are reading in an antenna
pattern called “Center.”
Figure 7: Each link that is connected to an element can be defined
form as described in Figure 4,
but designers can now define
the characteristics of the RF link
that is connected to the patch in
order to gain further insight into
the performance of the array. In
addition, users can have a full
transceiver model for each element
of the array, as opposed
to the previous model that only
allowed control of the gain and
phase of each element.
As shown in Figure 6, the text
file is being used to configure
Phased Array F and enables the
designer to define the array geometry.
This is a text line that is
written in the data file (highlighted
in blue) that indicates
to the software that the array
should be configured as a 4 x 4
array with a distance of half a
lambda between each element.
Additionally, each link has been
defined that is connected to an
element shown in the text highlighted
in blue as “RF A”(Figure
7). This command line indicates
that there is an amplifier with
a gain of 0 and a compression
point of 100 dB (indicated by
blue highlight). This example
is just one of many capabilities
in the VSS file-based phasedarray
model and an illustration
of how to work with this text file
to configure the array.
In Figure 8, the designer is
accounting for coupling by using
different antenna patterns for the
corner, the edges, and the center
of the 16-element array. The
simulation results of this 4 x 4
array show that each element is
isotropic.
The red trace shows a 16-element
array and the same pattern
is applied to those 16 elements.
The blue trace is the net result
of the configuration file shown
previously where a corner pattern,
an edge pattern, and a center
pattern were applied accordingly
to the 16-element array
(left side of Figure 8).
Conclusion
Figure 8: The designer is accounting for coupling by using different antenna patterns and the
different variations of the results of a 4 x 4 array
This brief overview has demonstrated
several key simulation
capabilities within VSS for
designing phased arrays. Designers
can account for coupling,
and, using the phased-array data
model, delve further into how
the element looks. Users can
go even further into these types
of simulations and account for
impedance in multi-in-multiple-out
(MIMO) operation of
an array. ◄
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