Ansoft Corporation Four Station Square, Suite 200 Pittsburgh, PA 15219-1119 USA (412) 261-3200

1. Ansoft HFSS 3D Post Processor and Calculator Ansoft Corporation Four Station Square, Suite 200 Pittsburgh, PA 15219-1119 USA (412) 261-3200

2. Topics Covered • General Functions • 3D Post-Processor Interface • Mesh Plotting • Excitations • Driven Solutions • Eigenmode Solutions • Field Plotting • Quantities, Geometry, Settings, Animation • Plot Management • Near/Far Field Processing • Computing and Displaying Antenna and EMI patterns • The Field Calculator • Calculator Layout • Examples

3. HFSS 3D Post-Processor Interface Field Calculator Icon Direct access to Field Calculator Data Menu Controls Source Excitations Radiation Menu Compute far field or field at a specific distance (“near” or “EMI” fields), display antenna parameters Side Window Similar to other modules.Contains coordinate fields,snap options, and drawingcommand prompts duringgeometry creation. Plot Menu (shown open) Most commonly used menu in Fields Processor; plot fields, mesh, and pattern data, control animations, manage plots, etc. Geometry Menu Define additional geometry for post-processing (lines, cutplanes, face and object lists, etc.) Graphical Display Window (E-Field Magnitude Display shown) All rotate, pan, and zoom view manipulations are available!

4. Plotting the Mesh • Choose Plot/Meshto view the mesh used in the solution • At least one object must be Selected • Mesh plot options include: • Scale Factor: Change size of displayed triangles/tetrahedra • Transparency: Set degree that objects show through mesh • Wire Frame, Hidden Line,or Shaded options control the display type of the mesh • The Surface Only checkbox limits mesh plotting to the faces of selected objects

5. Post-Processor Excitations • Excitations are controlled via the Data/Edit Sources • All ports or other sources can be controlled • Arbitrary magnitude and phase combinations • Excitation takes into account symmetry planes used in model construction • Excitation defaults to 1 watt at {Source1}, assuming a “full” model geometry • Wattage is reduced by appropriate factor for symmetry • {Source1} could be Port1, Mode1; Gap Source 1, etc.... NOTE: If the Solution run is a FAST Sweep, the field excitation can also be tuned to different frequencies within the sweep range. Adaptive and Discrete Sweep solutions contain single-frequency field data only.

6. Post-Processor Eigenmode Excitation • For an Eigenmode solution, individual mode excitations can be viewed • Eigenmode excitations can not be viewed in combination • Field Values are Normalized to the peak data value • Since there is no actual ‘input’ into the model (voltage source, port, etc.) exciting the resonant field behavior, the field magnitudes are all scaled relative to a peak value of 1.0 • Symmetry is again taken into consideration in excitation scaling Mag E, First Eigenmode in Cylindrical Dielectric Resonator

7. Post-Processor Field Quantities • The 3D Post Processor can directly display the listed quantities • All units in MKS system, regardless of units used in geometry construction • e.g. E-field is in V/m, H-field in A/m, etc. • Non-complex Magnitude quantities and all Vector quantities can be Animated vs. Phase • Shows changing field on the display geometry as excitation phase is rotated • Most Quantities can be displayed on surfaces, along lines, and within 3D volumes • Other quantities not listed can be derived using the Field Calculator and displayed in the graphical window following calculation

8. Post-Processor Plot Geometry • All field plots are generated on Geometry • The geometry list will include all objects built in the 3D modeler • Surfaces of all 3D solids and 2D sheets • Volumes of all 3D solids • Other default geometry for plotting are included • Principle Plane cutplanes (XY, XZ, YZ)* • Volume -all- (entire modeled volume) • Animation Surfaces for multi-surface frame lists • The user can create additional geometry for plotting using the Geometry menu • Cutplanes and face lists create surfaces • Line creates lines for integration, plotting *NOTE: The principle plotting planes (XY, XZ, and YZ) will recognize changes to the local coordinate system while in the post-processor.

9. Plotting Fields • To plot fields select Plot/Fields • Select a Plot Quantity in the left column • Select a Geometryon which to plot in the center column • (Optional) Select a Volume (domain) limit for plotting in the right column • For a single phase snapshot, enter desired phase and press OK (n/a for Cmplxquantities) • For Phase Animation, check the box and press OK • A plot settings dialog will launch with different entries depending upon the Quantityand Geometry selected (see next slide) NOTE that the above Plot Quantities can all be classified as containing either scalar or vector data

10. Plot Settings Dialogs: Stills Scalar SurfaceandVolume plots differ only in ability to fill in color maps Requesting a plot of a scalar value along a line results in a 2D graph, rather than a colormap plot in the graphcial display window

11. Plot Settings Dialogs: Animation • Selecting any AnimSurf entry in the On Geometry column results in a series of snapshots at different planar or object surface faces in the model • The appropriate variable will be given in the top field; user sets start, stop and step limits • Selecting the Phase Animation button results in display of multiple field plots (each at a different excitation phase) on the same geometry. • The variable is Phase; user sets limits • Checking the Store Framesbutton saves the snapshots as a separately viewable plots • Stored Frame Lists contain full plots that can be viewed from alternate angles, zooms, etc, and are maintained in memory until manually deleted (see Plot Management, next slide). • Leaving Store Frames unchecked creates a screen animation, which cannot be viewed from different orientations after creation, and is auto-matically deleted after the display is dismissed. Dialog for “AnimSurf XY” selection (Variable is Z position of XY planes) Dialog for Phase Animation

12. Plot Management • All 3D Field Plots are maintained in local memory, and can be managed during your post-processing session • Plots can be Saved and Opened in later sessions • Field views (scalar colormaps or vector plots) are saved as 3D Plots, while Graphs (plots of scalar quantities along lines) are saved as 2D Plots • Modifyallows you to re-select the settings for any currently open plot • Visibility allows you to show or hide any currently open plot. • Plots which are hidden are still in memory • Delete allows you to remove any currently open (visible or hidden) plot from memory. • To see the same plot again, you will have to re-create the plot using the Field pick in the Plotmenu • The Animationmenu pick allows management of various frame lists created using Store Frames • It can also be used to assemble user animations from any available individual plots!

13. Antenna and EMI Processing: Computing Fields • Projects with some form of open exterior boundary condition (either radiation or PML) can have fields calculated external to the modeled space. • Fields are computed using the Radiation menu, selecting Compute...Far Field or Near Field • Far Field is the field at a radius of infinity from the model’s global origin • Near Fieldpermits a user-entered radius • Fields are computed over user-specified angular ranges in phi and theta • Once computed, the fields are saved and may be plotted • If a plot of a near/far field cut outside of the computed range is desired, the fields will need to be re-computed first

14. Antenna and EMI Processing: Displaying Computed Fields • Computed fields are plotted using the Plot menu, Far Fieldor Near Field • Plot dialog permits plotting of antenna gain, directivity, axial ratio, polarization ratio, rE component fields, and rE total fields • Plots may be polar 2D, Cartesian 2D or polar 3D. • Displayed patterns can be saved as 2D Plots under the Plot...Save menu selection • The field computation and plotting does take symmetry planes into account

15. Antenna and EMI Processing: Displaying Computed Parameters • Computed Near and Far Field results can also be displayed in tabular format, showing the peak E-field magnitudes and locations • Far Field parameters include Antenna Parameters such as • Beam Area • Directivity • Radiated Power • Accepted Power • Efficiency • Maximum U (radiation power density)

16. The HFSS Field Calculator • Allows manipulation of modeled fields in the entire problem region • Permits direct access to , , and Poynting Vector with all real, imaginary, and vector components • Includes Scalar, Vector, Complex, Integration, and Differentiation functions • Results can be Output to Post-Processor Graphical Display window for color maps, vector plots, or 2D Graphs • Results can also be exported to external data files • Contains a large registry stack with standard RPN-type stack manipulation features • Push, Pop, Exchange, Rotate... • Is Unique to Ansoft HFSS!!

17. Accessing the Field Calculator • The Field Calculator is accessed using either the tool icon or the Data/Calculator menu pick • Once open, the calculator is a separate window from the 3D Post-Processor, and can be moved off of the Post-Processor background, minimized, etc.

18. Field Calculator Stack • The calculator stack builds from the top down • The top entry is the most recently added, with subsequently older entries flowing downward • Stack manipulation buttons are located immediately beneath the stack display • Push duplicates the top entry • Pop deletes the top entry • RlDn and Rlup ‘rolls’ the stack contents up or down • Exch swaps the two top entries • Clearempties the stack • Undoreverses the last operation NOTE: Most calculators using RPN and stack operation roll subsequent entries so that the bottom of the display is the latest value entered. The Ansoft Field Calculator uses the opposite convention. Therefore, to subtract 3 from 5, the stack might resemble: Scl: 3 Scl: 5 before the subtraction is performed, NOT the reverse as one might initially expect.

19. Field Calculator Data Types • Field Calculator stack entries are all classified by data type • Available data types are: • Complex Vector • Complex Scalar • Complex • Vector • Scalar • Volume • Surface • Line • The type of each stack entry is indicated with an abbreviation to the left of the stack entry • In some cases, certain mathematical operations require specific data types in specific positions in the stack

20. Field Calculator Layout • Field Calculator Functions are organized in columns, by classification • Input column functions create inputs[E-field, H-field, Poynting data, Geometry, Numerical values (scalar, complex, and vector), etc.] • General column functions work on most stack contents • Scalar column functions operate only on scalar quantities • Vector column functions operate only on vector quantities • Output column functions produce output from the calculator[graphs, color or vector displays, output files, integral evaluations, etc.]