Perform Transient simulation using IWF file and IQ probe
How to perform transient simulation using UWF file generated from Waveform Generator tool. The transient simulation in VISION allows to obtain the time domain response of a non-linear circuit excited by a modulated complex signal.
To begin this task, you will need:
- A licence of VISION System Architect. See Installation and licence setup.
- To have opened a schematic. See Create or select a schematic
-
Drag and drop the IQPROBE block from the palette window in
Template schematic section to the schematic editor
window.
Figure: IQPROBE template schematic 
-
Double-click on the AWG-IWF block to open the Parameters window.
Click on Waveform tab and set the path of the iwf file "signal16QAM.iwf"
. This file is in the folder "data_example" that is provided in the VISION
installation folder. The properties of the signal should be noted when
configuring the simulation: sampling rate and number of points.
Figure: Simulation mode 
-
Double-click on the EQN equation block in the schematic and check that
the parameters values corresponds to the signal's properties : "nb_sample" and
"symbol_rate".
Figure: Equation block 
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Double-click on the HPA block to open the Parameters window and
set the path to HPA model. The file can be found in the "data_example >
AWG-IWF_and_IQPROBE" folder: "HPA_U_HFBF.head".
Figure: HPA block 
-
Now we will set up the schematic to simulate a HPA-U-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 
-
Note that IQ_PROBE block can be found in the schematic and allow to
measure Power consumption (Pdc), input waveform (in), output waveform (out) and
signal's carrier frequency (fc). It is mandatory to measure input and output
waveform throught WMETER block with Incident & Reflected power
wave (A-B) option. This block will create a new dataset in the
simulation results identified by the name specified in the probe name (heren
"probe_iq"). Several IQ_PROBE blocks can be added in the schematic.
Figure: IQ_probe block 
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SIM_Controller block is configured to run an envelope transient
simulation with a nested sweep analysis. VAR block is used to sweep
signal input power and carrier frequency. Note that you can increase the
simulation speed by increasing the number of threads to be used, depending on
the performance of your machine. For this, use "Number of threads"
parameter. In the menu bar of the workspace window, click on the shortcut
to run the simulation.
Figure: Run the simulation 
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After the simulation, results are automatically displayed and stored in the imx
file available in the data explorer panel below the schematic tree. Drag
and drop the imx file (here, "sim_test.imx") in the data manager panel
available in the left. Depending on the probes placed in the schematic, several
datasets are available, sorting the results according to their type. Here,
probe_iq dataset is available, which organises the data in exactly
the same way as a real measurement of a circuit device using IQSTAR software.
The user has access to the same post-processing functions, such as ACPR and EVM.
Figure: Simulation results 