Antenna Array Workshop HFSS

Analysis of a Phased Array Antenna for
5G Applications
1 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

OUTLINE
• Goal: Design of a phased array antenna for 5G Applications (28GHz)
− Step1: Design of the single element antenna using the Antenna toolkit
− Step 2: Model the Unit Cell to approximate an infinite array
• Enforced field periodicity through Master/Slave boundary
• Assign “Floquet Port” to terminate waves propagating up the unite cell
• Use Optimetrics to run a parametric sweep for various scan angles
• Understand post processing of Floquet modes and plot far-field patterns
• Apply the Array Factor to the Element Pattern through the Antenna Array Setup toolkit
− Step 3: Model the desired array using Finite Array Domain Decomposition
• Apply beam steering to the array using theFinite Array Beam Angle Toolkit

Launching Electronics Desktop R19
• From windows Startup go to ANSYS ELECTROMAGNETICS 2018 > ANSYS Electronics Desktop 2018

Step1 : To Insert the HFSS Antenna Toolkit
• In the Menu bar go to View > ACT Extensions

• In the ACT Extensions Click on “Launch Wizards”
• Select HFSS Antenna Toolkit

Step1: Design of Square Patch Antenna with HFSS Antenna Toolkit
• Under Settings > Rectangular–Probe Fed

− Select Center Frequency [GHz] = 28
• Under Substrate Dimensions, expand “Material” > Click on Edit
− Select Roger RT/duroid 5880

continued…
• Under Substrate Dimensions change Substrate Height [cm] to 0.0787
• Click on Synthesis and the Finish
• Notice Patch Dimension Y [cm] 0.31

continued…
• A fully parametrized and ready to simulate design has been generated from the antenna toolkit
− In the Project Manager window Right Click on design “RectProbe_ATK (Driven Terminal)” and rename “SqPatchCoax”
− Click on “ SqPtachCox” and in the Properties windows change values to →

continued…
• In the modeler window expand Perfect E
− Select antenna and Ground (select antenna + CTRL select Ground)
− Right Click > Assign Boundary > Finite Conductivity
− Check (x) Use Material and Click on “vaccum”
− Select cooper from list

continued…
• Expand Boundaries under Project Manager and delete “antennaMetal”and “groundMetal”
• Click on “FiniteCond1” Right Click and rename to “Ant_GND_Metal”
• In the Menu bar under HFSS > Solution Type > unchecked Auto-Open Region
− Notice the “Radiation Boundary” in the model is now visible and listed under Boundaries in the Project
Manager window (AutoOpen1). In addition, a solid “Radiating Surface” is listed under vacuum in the 3D
modeler
The “Auto-Open Region” is unchecked because this solid would

be use later define the master/slave boundaries for the unit cell

continued…
• In the Modeler tree window under Solids expand PEC and delete “port_cap”
• Under Solids expand vacuum > ”RadiatingSurface” and click “Create Region”
• In the Properties window change “-Z Paddding Data” to zero (Flushes the bottom of the Waver Port to the Radiation
boundary (AutoOpen1))
• In the Project Manager expand Analysis > “ATK_Solution” > Delete “FF_Sweep”
• Click on “Sparam_Sweep” and under properties change Start/Stop/Count to 250/35/201

continued…
• Go to Menu bar, File > Save, “Antenna_Array_Flow”
• From the toolbars select Simulation > HPC Options > Edit (1)
− Check Automatic Settings and select 4 for Total Enabled Cores
• From the toolbars select Validate to check that there are no errors (2)
• From the toolbars hit Analyze All to launch Simulation
(1)
(2)

Step1: Design of Square Patch Antenna with HFSS
Antenna Toolkit continued…
• In the Project Manager Window expand Results. Double Click on the predefined results for Return Loss,
Radiation Pattern, 3D Polar Plot and Smith Chart

Step2 : Create the Unit Cell
• In the Project Manager window select design “SqPatchCoax,” Right Click > Copy, select project
“Antenna_Array_Flow” Right Click > Paste
• Right Click on “SqPatchCoax1” and rename to “SqPatch_UnitCell”
• In the Menu Bar go to HFSS > Solution Setup and switch to Driven Modal (the solution setup is changed
because a “floquet port” will be use to terminate the unit cell)
• Draw the Lump port:
− In Menu bar go to Modeler > Grid Plane > XZ
− In Menu bar go to Draw > Rectangle and Click F4 on keyboard to change the “Drawing Entry Mode to Dialog”
To revert back to “Point Entry Mode” Click F3 on keyboard
− Enter the variables bellow
• For Position (-coax_inner_rad,feedY,subH), Xsize (2*coax_inner_rad), Zsize (-subH)
• Hit OK

(1)
Step2 : Create the Unit Cell continued…
• Expand the Modeler Tree, CTRL select -> coax_pin, feed_pin, coax -> DELETE (1)
• In the Modeler tree under Sheets Expand Finite Conductivity -> Ground (2)
− Select “Subtract” boolean operation and DELETE (2)
− Under Unassgined Delete “NewObject_92FNEI”
• In the Modeler Tree under sheets select Unassigned > Rectangle 1
− Right Click Assign Excitation > Lumped Port
− Click Next
− Define Integration Line
• Snap to top (snap1) and bottom (snap2) of sheet Rectangle 1
− Click Next and Finish
Snap1
Snap2

• Infinite Array using Master / Slave Boundary
2
Slave The Master and Slave boundaries force a periodicity in the fields corresponding
to the periodicity of the array. It does this by mapping the fields from the
Master boundary to the corresponding Slave boundary. These fields are
identical to each other with the exception of a potential phase shift. This phase
shift is what will be used to enforce the progressive phase delay across the array
that steers the beam.
Master and Slave boundaries use UV coordinate systems to determine the field
mapping. Since Master/Slave pairs are defined on opposite sides of the unit cell,
1 the slave’s UV coordinate system should be a simple linear translation of the
Master master’s UV coordinate system. If done correctly, the distance between each
boundary’s UV coordinate system should correspond to the distance and
direction of the next adjacent element in the array.
UV coordinate systems are defined by selecting two points. The first point
corresponds to the coordinate system’s origin. The second point defines the U
axis’ direction.
The phase delay between Master / Slave boundary pairs is defined on the Slave
boundary’s Phase Delay Tab. It can be defined as a phase delay or in terms of
the array’s scan angle. If the array’s scan angle is chosen, HFSS will determine
the appropriate phase delay to properly steer the beam.
UV Co-ordinate
System

• In Modeler Tree under “Solids” expand vacuum > Radiating Surface and Click “Create Region”
− In the Property windows change values to 0 and just keep +Z padding
• In Project Manager window expand “Boundaries” and delete “AutoOpen1”

• Define Master/Slave Boundary
− Click F on keyboard to switch to Face selection mode
− Select face on the +Y axis
− Right Click, select Assign Boundary > Master
− Define U Vector Line

• Define Master Boundary 1
− Name: Master1
• U Vector: New Vector…
• Change the Cursor Movement Mode to 3D
• From HFSS’s Menu Bar select Modeler > Movement Mode > 3D
• Left click on the vertex in the upper, left corner of the face (1)
• Left click on the vertex in the upper, right corner of the face (2)
• Click Ok button
(2)
(1)

• Define Slave 1 Boundary
− Hit short key F and select top face
− Hit B on keyboard to select face behind. Right Click select “Assign Boundary”> “Slave”

• Slave Boundary Window
− Name: Slave1
• Master Boundary: Master1
• Click Next button
(2)
(1)

• Create Slave1 Boundary (Continued) Note: The phase delay between Master / Slave boundary
pairs defines the progressive phase shift applied across the
− Phase Delay Window array. This is used to simulate the array under different scan
• Phi: Phi_Scan conditions. In this workshop the phase delay is defined in
terms of the scan angle which is controlled through the
• Assign 0 deg to the variable Phi_Scan variables Phi_Scan and Theta_Scan.
• Theta: Theta_Scan
• Assign 0 deg to the variable Theta_Scan
− Click Finish button
• Verify the Master/Slave boundary setup
− In the Project Manager select the SQPatch_UnitCell > Boundaries > Slave1 branch
− Make sure the Master and Slave Boundaries are highlighted in the 3D Modeler and looks like the picture
2
Slave
1
Master

• Define Master 2 Boundary Note: This procedure defines a single Master / Slave
boundary pair. Two additional pairs need to be
− Click F on keyboard to switch to Face selection mode defined to complete the definition. The next few
− Select face on the +X axis pages will step through the creation of these
additional boundaries, but with far less explanation.
− Right Click, select Assign Boundary > Master
− Define U Vector Line
• Name: Master1
• Click Ok button
(1)
(2)

• Define Slave Boundary 2 2. Hit B on keyboard to select back face.
Right Click select “Assign Boundary”> “Slave”
1. Hit short key F and select top face
4. Define U Vector, remember 3D

movement mode (modeler >
movement mode > 3D)
3. Name boundary Slave 2 and select Master

Boundary = Master 2 and define U Vector (1)
(2)
Note: The Phase Delay Window is already filled in. When

the phase delay is determined by the array’s scan angle all
Master/Slave boundary phase delays are calculated based
off the scan angle.

• Unit Cell with Two pairs of Master/Slave Boundaries
2
Slave 2
1
Slave 1
1
Master 1 2
Master 2
Note: The UnitCell design should have2 pairs of Master / Slave boundaries totaling 4 boundaries all together. Each pair should be
defined on opposite sides of the unit cell. Each boundary pair should have UV coordinate systems defined on them in such a way that
the U-axes point in the same direction and the V-axes point in the same direction. The only difference being a linear translation of their
origins across the unit cell.
In addition, each slave boundary should use the Scan Angle method for defining the phase delay between the fields on the Master and
Slave boundaries. This scan angle should be controlled by two variables; Phi_Scan and Theta_Scan.

• Create Floquet Port Excitation
− Switch to Face selecting mode by hitting short key F on keyboard
− Left click the face on top of the UnitCell Object to select it
− In the 3D Modeler window, right-click and select Assign Excitations > Floquet Port…
− Floquet Port General Tab:
• A Direction: New Vector
• Left click on the bottom, left corner vertex of the UnitCell
• Left click on the bottom, right corner vertex of the Unit Cell
• B Direction: New Vector
• Left click on the bottom, left corner vertex of the UnitCell
• Left click on the top vertex of the Unit Cell
• Click Next> button

• Floquet Modes
− Floquet Port: Modes Setup Window
• Click Modes Calculator… button
• Number of Modes: 20
• Frequency: 28 GHz
• Scan Angles Phi:
• Start: 0 deg
• Stop: 90 deg
• Step Size: 10 deg
• Scan Angles Theta:
• Start: 0 deg
• Stop: 60 deg
• Step Size: 10 deg
• Click OK button
• Observe the attenuation values for the first 20 modes
• Change Number of Modes to 2
− Floquet Port: Post Processing Window
− Floquet Port: 3D Refinement Window
• Make sure all modes have their Affect Refinement Unchecked
• Click Finish button
Note: The modes calculator determined there are only 2 strong propagating modes with 0dB/length attenuation and 4
with 27dB/length of attenuation. Since the distance from the unit cell to the floquet port face is 0.357 cm, the total
attenuation is only (50.32 dB/cm * 0.357 cm = 17.9 dB). To attenuate these modes by > 50dB we need separate the
floquet port from the unit cell by a distance of roughly 1 cm

• To change the distance between floquet port and unit cell
− In the Modeler Tree under Solids expand Vacumm > Radiating
Surface and double click create region
− In the +Z padding type 1 cm
Note: The radiated waves from the array will be terminated in the Floquet Modes defined by the Floquet Port Setup. Each Floquet Mode
is a plane wave supported by the periodic structure. They also correspond to the different beams an array might support. They come in
two polarizations; Transverse Electric (TE) and Transverse Magnetic (TM). Assuming the Floquet Port is parallel to the XY plane, TE modes
are +/- Phi polarized waves and TM modes are Theta polarized wave. The dominant modes are the TE 00 and TM00 modes which
correspond to the phi and theta polarized components of the array’s main beam. All other mode indexes correspond to various grating
lobes.
The energy associated with any mode not defined in the Floquet Port will be short circuited back into the model so its important to
include all propagating mode. However, which modes propagate depends on the angle the array is scanned. The Mode’s Calculator was
added to make choosing the appropriate modes easier. It will search a scan volume defined by Theta and Phi angles and report the
modes with the smallest attenuation constant over that scan volume. Make sure any mode not included in the port experiences at least
50dB of attenuation as it propagates from the element to the port. That way it has little chance to affect the predicted performance. The
attenuation is calculated in dB/length so the total attenuation can be computed by multiplying the calculated attenuation by the unit cell
height (27.10dB/length)*1.8cm = 50dB of attenuation for mode 3, 4, 5, 6. All modes listed above mode 3 have 0dB/length of attenuation
so they must be included.
Its important to note that the height of the Unit Cell impacts how many modes need to be included in the Floquet Port Setup. Non-
propagating modes can be removed from the setup by choosing a height large enough to make sure they experience the recommended
attenuation for elimination.

• Test the unit cell for beam steering:
• Scan the main beam from boresight to 60 degrees:
− In the Project Manager Right Click on Optimetrics > Add > Parametric
− Under “Sweep Definitions” Click on Add
• Scan on Phi (Phi_Scan) from 0 to 90 degrees in step of 90 degrees and Click Add
• Scan on Theta (Theta_Scan) from 0 to 60 degrees in step of 15 degrees and Click Add
• Hit Ok

• The table tab shows the angle beam steered for “Theta_Scan” from 0 to 60 degrees for a “Phi_Scan” on the 0
and 90 degrees cut
• Under Options Check “Save Fields and Mesh”
• Under Options Check “Copy geometrically equivalent meshes” and “Solve with copied meshes only”
− Since there are not physical variations on the structure, only the scan angle, enabling this feature will reuse the mesh for each solution
Note: The active impedance of an array changes as the array is scanned in different directions. Since the scan angle is fixed through
the Theta_Scan and Phi_Scan variables used in the Slave Boundaries, the unit cell model needs to be simulated explicitly at different
scan angles to capture the element’s behavior for each of these conditions.
The easiest way to perform the analysis over the scan volume is to use the Optimetrics License to create a Parametric Sweep of the
Theta_Scan and Phi_Scan variables. The parametric sweep created here scans the array from boresight out to 60. This is determined
by the Definitions Tab which swept the Theta_Scan variable from 0deg to 60deg. The Phi_Scan is set for 0deg and 90deg, this
parametric sweep corresponding to the array scanning along the XZ plane and YZ plane.

• Define Distribution List
− From HFSS’s Menu Bar select Tools > Options > HPC and Analysis Options…
− Select Local and click Edit.. button
− Analysis Configuration Window
− Check Use Automatic settings
− Number of variation to distribute = 4 (Solves two variations in parallel)
• Configuration Name: Distributed Analysis
• Machine Details:
• Local machine
• Number of Cores: 4
• Click OK button
− Click Make Active button
− Click OK button
Note: Every Optimetrics License comes with 2 DSO (Distributed Solve Option) licenses allowing a user to
run 2 instances of a parametric sweep at the same time. This speeds up the analysis of the scan volume
sweep. The number of parametric instances run simultaneously and the number of cores each instance
uses is controlled by setting up an Analysis Configuration in the HPC and Analysis Options window.
This example assumes that the computer running the analysis has 4 cores and there are 4 DSO licenses
available.
If the computer running this sweep does not contain 4 cores or you do not have 4 DSO licenses you will
need to reduce the number of Tasks and Cores appropriately. If you have more cores and licenses available
you can further speed up the analysis by adding more tasks.

• From HFSS’s Project Manager, Right Click Design “SqPatch_UnitCell”
− Select Analyze All from the pop-up menu
• Note: Using the Analyze All From HFSS’s tool bar will analyze all setups defined in the Design (including “ATK_Solution” and
the “ParametricSetup1”)
− After analysis is complete save the project

• Select the menu item File > Save
• Review solution Data
− From the toolbars select tab Results > Solution Data
− Select the Profile tab to view solution information
− Under Design Variation Click on …
• Select other than the nominal design
• Notice the mesh is reused for every parametric sweep
− Click Close button

• Plot the “Active Element Impedance” over Scan Volume
− Select the menu item HFSS > Results > Create Modal Solution Data Report> Rectangular Plot
• Trace Tab
• Solution: ATK_Solution : Sparama_Sweep
• Domain: Sweep
• Category: S Parameter
• Quantity: S(1:1,1:1)
• Function: dB
• Families Tab
• Phi_Scan Value: All
• Theta_Scan Value: All
• Click New Report button
• Click Close button
Note: This plot shows the Return Loss vs.

Frequency for each scan angle solved
during the parametric sweep. Multiple
curves were created because the
Phi_Scan and Theta_Scan Values were set
to All (more than one value) on the
Families Tab. The plot shows that each
scan angle produces a unique impedance
that produces a worse return loss as the
frequency and scan angle increases.

• Create a Radiation Setup
− Select the menu item HFSS > Radiation > Insert Far Field Setup > Infinite Sphere
• Infinite Sphere Tab
• Name: Infinite Sphere 1 (default)
• Phi: (Start: 0, Stop: 3600, Step Size: 1)
• Theta: (Start: -180, Stop: 180, Step Size: 1)
Click the OK button
Note: The Infinite Sphere Tab of the Far Field Radiation
Sphere Setup determines what directions the far-field
pattern is calculated for. This setup will calculate the far-
field pattern for a hemisphere extending above the XY plane.
Theta is defined from -180 deg to +180 deg so the boresight
direction ends up in the middle of the plots we are about to
create.

• Create Far-Field Radiation Pattern
− Select the menu item HFSS > Results > Create Far-Field Report> Radiation Pattern
− Or from the toolbar Results > Far Field Report > Mag/Ang Polar
• Trace Tab
• Solution: ATK_Solution: LastAdaptive
• Geometry: Infinite Sphere 1
• Domain: Sweep
• Primary Sweep: Theta
• Category: Realized Gain
• Quantity: RealizedGainTotal
• Function: dB
• Families Tab
• Phi: 0
• Freq: 28GHz
• Phi_Scan: 0 deg
• Phi: 90
• Freq: 28GHz
• Phi_Scan: 90 deg
Note: These curves show HFSS’s calculation of the array’s radiation pattern for
different scan angles. They result from the infinite array having a uniform magnitude
excitation and a progressive phase shift needed to steer the main beam to the
requested scan angle. However, the far-field integration is only performed over the
− Change Report Name relatively small unit cell area producing the broad beam patterns displayed here.
• In Project Manager window select Realized Gain Plot1 These patterns do not represent the Embedded (Active) Element Pattern used to
• In Properties window: recreate the finite array’s pattern through Pattern Multiplication. The Embedded
• Name: Realized Gain Phi 0 Cut Element Pattern is independent of scan angle which these results clearly depend on.
• Display Type (Optional) : Rectangular Plot
• In Project Manager window select Realized Gain Plot2
• Repeat Steps above and Name: Realized Gain Phi 90 Cut

• The Far Field Patterns can be plotted as a 2D Polar Plot or as a Rectangular Plot

• Create Embedded Element Pattern Data Table
− Select the menu item HFSS > Results > Create Far-Field Report> Data Table
− Or from the tool bar Results > Far Field Report > Data Table
• Trace Tab
• Geometry: Infinite Sphere 1
• Domain: Theta,Phi
• Primary Sweep: Theta_Scan
• Function: dB
• Families Tab
• Theta: 0deg, 15deg, 30deg, 45deg, 60deg
• Note: You may need to change the values using the
button in the Edit … column of the variable.
• Phi: 0 deg
• Note: You may need to change the values using the
button in the Edit … column of the variable.
• Phi_Scan: 0 deg
• Freq: 10.8GHz
• Theta: 0deg, 15deg, 30deg, 45deg, 60deg
• Phi: 90 deg
• Freq: 10.8GHz

• Change Report Name
• In Project Manager window select Realized Gain Table 1 Note: Realized Gain is plotted here because its value is
• In Properties window: affected by the element’s mismatch. Since the impedance
• Name: “Embedded Element Pattern Phi_Scan 0” changes as a function of scan, this quantity is typically what
is used to represent the element’s pattern instead of Gain.
• In Project Manager window select Realized Gain Table 2
• In Properties window:
• Name: “Embedded Element Pattern Phi_Scan 90”
Note: The Embedded (Active) Element Pattern can be extracted from the radiation patterns just plotted by
taking the one point on each curve corresponding to the scan angle used to produce that curve. For instance,
the Embedded Element Pattern for the angle (theta, phi) = (15deg, 90deg) would correspond to the (theta, phi) =
(15deg, 90deg) point on the RealizedGainTotal curve associated with Theta_Scan = 15deg and Phi_Scan = 90deg.
All the other points on the curve would be discarded. The points that are part of the Embedded Element Pattern
are highlighted with blue boxes in the above data table.

• Create a new Coordinate System
• In the Menu Bar : Modeler > Coordinate System > Create > Relative CS > Offset
• Snap to the top of the patch
• In the modeler tree expand Double Click on New Coordinate System Relative CS1
• Under Name : Scan_CS
• Origin : 0cm, 0cm, subH
• X Axis: cos(Theta_Scan)*cos(Phi_Scan) ,cos(Theta_Scan)*sin(Phi_Scan) ,-sin(Theta_Scan)
• Y Axis: -cos(Theta_Scan)*sin(Phi_Scan) ,cos(Theta_Scan)*cos(Phi_Scan) ,0mm
• Hit OK
Note: Scan_CS is a relative coordinate system parameterized so the z-axis always points in the scan direction defined by
Theta_Scan and Phi_Scan. You can visibly verify this in the 3D Modeler by switching to the Scan_CS coordinate system,
changing the value for Theta_Scan to 60deg and observing where the z-axis points.

• Create New Radiation Infinite Sphere
− From HFSS’s Menu Bar select
HFSS > Radiation > Insert Far Field Setup > Infinite Sphere…
− Infinite Sphere Tab:
• Name: Infinity Sphere Phi_Scan 0
• Phi Start: 0 deg
• Phi Stop: 0 deg
• Phi Step: 10deg
• Theta Start: 0 deg
• Theta Stop: 0 deg
• Theta Step: 10 deg
− Coordinate System Tab:
• Select Use local coordinate system
• Choose from existing coordinate systems: Scan_CS
− Click OK button
− Repeat, From HFSS’s Menu Bar select
HFSS > Radiation > Insert Far Field Setup > Infinite Sphere…
− Infinite Sphere Tab:
• Name: Infinity Sphere Phi_Scan 90
• Phi Start: 90 deg
• Phi Stop: 90 deg Note: Setting up the infinite sphere using this coordinate
• Phi Step: 10deg system (Scan_CS) allows us to plot the Embedded
• Theta Start: 0 deg Element Pattern while keeping theta and phi at a
• Theta Stop: 0 deg constant 0deg.
• Theta Step: 10 deg
− Coordinate System Tab:
• Select Use local coordinate system
• Choose from existing coordinate systems: Scan_CS
− Click OK button
• Create Far-Field Radiation Pattern
− Select the menu item HFSS > Results > Create Far-Field Report> Radiation
Pattern
• Trace Tab
• Domain: Infinite Sphere Phi_Scan 0
• Primary Sweep: Theta_Scan
• Function: dB
• Families Tab
• Theta: All
• Phi: All
• Freq: 28 GHz
• Phi_Scan: 0 deg
• Domain: Infinite Sphere Phi_Scan 90
• Theta: All
• Phi: All
• Freq: 28 GHz
• Click Add Trace
− Change Report Name
• In Project Manager window select Realized Gain Plot 1
• In Properties window:
• Name: Embedded Element Pattern From Scan_CS

• File > SAVE
Note: This pattern can then be used to predict a finite array’s pattern through the method of pattern
multiplication.
𝐸𝐹𝑖𝑛𝑖𝑡𝑒 𝐴𝑟𝑟𝑎𝑦 = 𝐸𝐸𝑚𝑏𝑒𝑑𝑑𝑒𝑑 𝐸𝑙𝑒𝑚𝑒𝑛𝑡 ⋅ 𝐴𝑟𝑟𝑎𝑦𝐹𝑎𝑐𝑡𝑜𝑟
To fill in the rest of the pattern additional simulations would need to be performed at different scan angles.

• Apply array factor to Unit Cell for a 4 x 4 array pattern
using “Antenna Array Setup toolkit”
− In the Project Manager, right Click on Radiation >
Antenna Array Setup
− Select Regular Array Setup
− Input values for
• Distance Between Cells:
• In U Direction: subX
• In V Direction: subY
• Number of Cells:
• In U Direction: 4
• In V Direction: 4
• Scan Definition: Use settings from Slave Boundary

• In the Project Manager under Results double Click on Plots
− Embedded Element Pattern Phi_Scan 0
− Embedded Element Pattern Phi_Scan 0
− Embedded Element From Scan_CS

Step 3: Design of Finite Array Doman Decomposition Method (DDM)
• Copy/Paste Unit Cell Design
− In the Project Manager window, select: SqPatch_UnitCell (DrivenModal)
• Right-click and select the menu item: Edit > Copy
− In the Project Manager window, select: “Antenna_Array_Flow”
• Right-click and select the menu item: Edit > Paste
• Rename Design
− In the Project Manager window, select: SqPatch_Unitcell (DrivenModal)
• Right-click and select the menu item: Edit > Rename
− Rename design to: SqPatch_DDM
− In the Project Manager window, minimize the Unit Cell design and expand
the Finite Array design
Note: We don’t want to invalidate the solution of the unit cell simulation because we will
want to use the mesh from this solution to solve the finite array design. By copy/pasting
the unit cell design to create the finite array design, we are ensuring that the unit cell used
to build the finite array is geometrically-equivalent to the one used in the unit cell
simulation --- in other words, we can safely use the same mesh in both designs.

Step 3: Design of Finite Array Doman Decomposition
Method (DDM)
• Remove Floquet Port
− In the Project Manager window, expand the Excitations list
• Select FloquetPort1
• Edit > Delete
Note: When we solve the finite array, we are no longer using

Floquet analysis. The radiation boundary condition assigned to
the single unit cell will be used across all elements of the finite
array. This could be an ABC, PML or FE-BI.
• Add Radiation Boundary

− In the 3D Modeler window, right-click and select Select Faces
− In the 3D Modeler window, select the top face where the Floquet port was once
defined
− In the 3D Modeler window, right-click and select Assign Boundaries > Radiation
− Select OK

Step 3: Design of Finite Array DDM continued…
• In the Project Manager window expand Analysis and double Click on setup “ATK_Solution”
− Under General tab set “Maximum Number of Passes” to 1
− Under Options unchecked “Do Lambda Refinement”
− Under Advanced, check Import Mesh and Click on Setup Link
− Check Use This Project
− Select Source Design as “SqPatch_UnitCell”
− Source Solution ATK_Solution_Last Adaptive

• Map variable from source design
• In the Additional mesh refinement tab select “Ignore mesh
operation in target design”
• Click Ok on Setup Link
• On the Advance tab check Save Fields and Save radiated fields only
• Click OK for the setup
• Expand solution setup (ATK_Solution) and Disable Sweep
(Sparam_Sweep)

• Create Finite Array

• HFSS >> Model >> Create Array…
− General tab
• Check the box for Visible
• Name: Phased Array
• Define Lattice Vectors and Array Size
Boundary Size
For A Vector Master 1 4
For B Vector Master 2 4

Air buffer region
mimics DDM
− Select Apply
− Select Close
Note:
• Active elements: the geometry of the unit cell is there, ports are active
• Passive elements: the geometry of the unit cell is there, ports are perfectly terminated
• Padding elements: the geometry of the unit cell is removed (cell is filled with air), ports do not exist
In the finite array simulation, padding elements border the entire array. These are not visible to the user. When comparing
the finite array DDM results to an explicitly drawn array of the same configuration, one must remember to include the air
padding buffer around the model as shown below.

• Analysis Configuration
• High Performance Computing Configuration
− Finite Array Distributed Domain Method requires an HPC license. This method splits the problem into “domains” and solves the
different domains in parallel for a more efficient (less RAM, less time) solve. The HPC Analysis Configuration will allow us to
specify the number of cores and the number of tasks we would like to run. The number of tasks will correspond to the number
of domains to run in parallel. This method requires at least 3 tasks; one task will be the “head node” and the other two tasks
are domains.
− “Use Automatic Settings” option requires only total number of available cores. Number of domains is determined
automatically based on the size of the problem and available resources.
• Configuring HPC Settings

− From the Analysis Options Toolbar, select Local configuration
− Click the Edit Active Analysis Configuration button
− In the Analysis Configuration window, change the following:

• check Use Automatic Settings
• Cores: 4
• RAM Limit(%): 90
− Click the OK button to finish and close configuration window
Note: Additional machines can be added to the

configuration to further accelerate solutions.

• File >> Save
• Note: Before running the simulation disable
or delete the optometric setup.
• HFSS >> Validation Check
− Select Close
• HFSS >> Analyze All
Note: This warning message is ok! Remember we

started this simulation by importing a well-
converged mesh from the unit cell model and then
we limited number of adaptive passes to 1

• After the simulation is completed Right Click on Excitations > Edit Sources
− Notice only one element is excited
− You can choose to input the Magnitude and Progressive phase shift manually (1W for Magnitude and 0
degrees for Phase). In this workshop we choose the Toolkit to input these values through variables
− Hit Ok
• Go to HFSS > Toolkit > Finite Array Beam Angle
− Leave everything as zero for boresight radiation
− Click Calculate, Apply to Edit Sources and Done

• Right Click on Excitations > Edit Sources
− Notice the new equations brought in by the toolkit for Magnitude and Phase
• If you check the Properties window for the design you will see the values for these
variables

• Radiation Setup
− In the Project Manager Window, right-click on Radiation and select Insert Far Field Setup
>> Infinite Sphere…
• Name: Elevation
• Phi
• Start: 0deg
• Stop: 90deg
• Step: 90deg
• Theta
• Start: -180deg
• Stop: 180deg
• Step: 1deg
− Select OK
• Realized Gain dB
− In the Project Manager Window, right-click on Results and select Create Far Field Report
>> Radiation Pattern
− In the Context field, select Elevation from the Geometry drop-down menu
− Under Trace Tab:
• Quantity: Realzied GainTotal
• Function: dB
− Select New Report
− Select Close
− Click under Results on Realized Gain Plot 1
− In the Properties window change Name: “Realized Gain Plot Beam Steered”

• Radiation Setup
− In the Project Manager Window, right-click on Radiation and select Insert
Far Field Setup >> Infinite Sphere…
• Name: 3D
• Phi
• Start: 0deg
• Stop: 360deg
• Step: 1deg
• Theta
• Start: -180deg
• Stop: 180deg
• Step: 1deg
− Select OK
• Realized Gain dB
− In the Project Manager Window, right-click on Results and select Create
Far Field Report >> 3D Polar Plot
− In the Context field, select 3D from the Geometry drop-down menu
− Under Trace Tab:
• Quantity: Realzied GainTotal
• Function: dB
− Select New Report
− Select Close
− Click under Results on Realized Gain Plot 1
− In the Properties window change Name: “3D Realized Gain Beam
Steered”

• Beam Steering
• Click on design “SqPatch_DDM”
− In the Properties Window change variable ScanAngleTheta = 30deg
and ScanAnglePhi = 90
• In the Project Manager
− Under Results double Click on Realized Gain Plot Beam Steered and
3D Realized Gain Plot Beam Steered

Antenna Array Workshop HFSS

Uploaded by

Copyright:

Available Formats

Antenna Array Workshop HFSS

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Antenna Array Workshop HFSS

Uploaded by

Copyright:

Available Formats

What are the steps involved in designing a phased array antenna?

What are the steps involved in designing a phased array antenna?

What is the goal of modeling the unit cell?

What is the goal of modeling the unit cell?

Analysis of a Phased Array Antenna for

1 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

2 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

3 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

• In the Menu bar go to View > ACT Extensions

4 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

• Under Settings > Rectangular–Probe Fed

5 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

6 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

7 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

8 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

The “Auto-Open Region” is unchecked because this solid would

9 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

10 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

11 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

12 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

13 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

14 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

15 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

16 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

17 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

18 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

19 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

20 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

21 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

22 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

4. Define U Vector, remember 3D

3. Name boundary Slave 2 and select Master

Note: The Phase Delay Window is already filled in. When

23 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

24 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

25 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

26 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

27 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

28 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

29 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

30 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

− After analysis is complete save the project

31 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

Note: This plot shows the Return Loss vs.

32 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

33 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

34 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

35 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

36 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

37 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

38 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

40 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

• File > SAVE

41 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

42 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

43 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

44 © 2017 ANSYS, Inc. December 5, 2019 ANSYS Confidential

Note: When we solve the finite array, we are no longer using

• Add Radiation Boundary