how to perform an antenna-type analysis in VISION? This type of analysis is in fact a
mixed electric and electromagnetic type under the assumption of radiation in the far-field.
The amplitude and phase control of each patch is possible thanks to the joint use of a
particular source block and of the variable block. This allows a precise analysis of the
interactions between nonlinear memory blocks located before an antenna and for which the
mismatch conditions are taken into account.
For example, we will analyze the performances of an antenna model associated
with an HPA-B-HF model. The simulation presented here is based on an antenna array
of 4x4 patches, which introduces the concept of multi-block. This concept is general
and useful when dealing with a large system with several patches controlled by
several RF front-ends. The basic steps to perform this simulation are as
follows:
Drag and drop the ANTENNA block from the palette window in
Linear distributed section to the schematic window.
Figure: Antenna block
Double-click on the Antenna block to open the Parameters window.
Fill in the Model parameter file field with the absolute or relative path
of your extracted model in device modeler with the extension ".head". There is
an automatic detection of the number of inputs. For example here 16 inputs are
detected.
Figure: Antenna block parameters
Now we will set up the schematic to simulate a HPA-B-HF model. Drag and drop
the HPA block from the palette window in Non linear section
to the schematic window. Double-click on the HPA block to open the
Parameters window and fill in the Model parameter file field
with the absolute or relative path of your extracted model in device modeler
with the extension ".head".
Figure: HPA block
4. From this point, we will create a multi-block that allows the amplifier
block to be easily connected with the antenna. See Create a multiblock and add to Palette for more details. Right-click on the
amplifier block and select “Create a Multi-block”. Choose a name for the
multi-block, example: My_multiblock.
Figure: Edit multiblock name
5. My_Multiblock now appears in the palette in the Multi-block section. By
clicking on one port of this multi-block, we can adjust the cardinality of the
block. By cardinality, we mean here the number of parallel repetitions of the
multi-block. It is an efficient way to manage very large systems with which it
is not possible to make the connections manually. In this example, a cardinality
of 16 is necessary to control the 16 patches of the antenna.
Figure: Edit cardinality
Drag and drop the Freq block from the palette window in
Source section to the schematic window. Double-click on the
Freq block to open the Parameters window and set the value to
28e9 Hz. Connect the Freq block output [+] with the freq
[fc] of the ANTENNA block.
Figure: Frequency block
Drag and drop a second Freq block. Then create a multi-block
My_Freq and edit the new block. Double-click on the
Freq block to open the Parameters window and set the value to
28e9 Hz. Choose a cardinality of 16 and connect the My_Freq block
output [+] with the freq [fc] of the My_Multiblock
block.
Figure: Frequency multiblock
Drag and drop the Antenna CW source block from the palette window
in Source section to the schematic window. This source is
different from classical Antenna CW source source as this is a
multi-block directly usable for driven multi-block elements. Double-click on the
Antenna CW source block to open the Parameters window. The
parameters Amplitude and Phase must be fill by any variable or equation name.
The block load automatically the variable name and increment the
cardinality.
Figure: Antenna CW source
An equation block is used to define the therorical relationship between all the
patch's phases. The source power is kept constant. For this example we have
chose 2 variables : Phase_shiftX and Phase_shiftY. These 2 variables are the
phase difference between two consecutive patches following the Horizontal (X)
and vertical (Y) distribution of the antenna array.
Figure: Equation block and VAR block
Drag and drop the SIMCTRLR simulation controller block from the
palette window in Simulation controls section to the
schematic window. Double-click on the SIMCTRLR block to open
the Parameters window, change the simulation name to "sim0" and set CW
simulation for Simulation mode and Sweep analysis - nested
sweep for Analysis type.
Figure: Simulaition Controller
The design can now be simulated. In the menu bar of the workspace window, click
on Simulate>Run simulation or on the shortcut . The output console is displayed:.
Figure: Design to simulate
Figure: Console
The console window contains the simulation time, the simulation mode, the
repertory of the results, and also any warnings and errors encountered during
the simulation.
When closing the console window, simulation results appear in the application
tree in the folder named after the simulation. To see how to display antenna
simulation results, see Antenna simulation results.
. The output console is displayed:.
