© 2011 ANSYS, Inc. February 24, 20121
ElectromagneticsR14 Update
Greg Pitner
© 2011 ANSYS, Inc. February 24, 20122
HFSSVersion 14
© 2011 ANSYS, Inc. February 24, 20123
HFSS Overview• Advanced Integrated Solver Technologies
– Finite Arrays with Domain Decomposition– Hybrid solving: FEBI, IE Regions
• Physical Optics Solver in HFSS‐IE• Transient Finite Elements improvements• Huray surface roughness model• Usability Enhancement
– Radiated fields…..– Network installation improvements– 3D modeler improvements
• CAD Integration in Workbench– Improved Multiphysics flow
© 2011 ANSYS, Inc. February 24, 20124
Finite Arrays with Domain DecompositionEfficient solution for repeating geometries (array) with domain decomposition technique (DDM)
© 2011 ANSYS, Inc. February 24, 20125
A Review: Domain Decomposition
Distributed memory parallel solver technique
Distributes mesh sub‐domains to network of processors
Significantly increases simulation capacity
Highly scalable to large numbers of processors
Automatic generation of domains by mesh partitioning
• User friendly• Load balance
Hybrid iterative & direct solver• Multi‐frontal direct solver for each sub‐
domain• Sub‐domains exchange information
iteratively via Robin’s transmission conditions (RTC)
Distributes mesh sub-domainsto networked processors and memory
© 2011 ANSYS, Inc. February 24, 20126
Finite ArraysSolve large finite array designsEfficient setup and solutionDefine unit cell and array dimensions• Efficient geometry creation and representation
Efficient Domain Decomposition solution
• Leverages repeating nature of array geometries
• Only mesh unit cell• Virtually repeat mesh throughout array
Post‐process full S‐parameter• Couplings included• Edge effects included3D field visualizationFar field patterns for full array
Memory efficient Enabled with the HFSS HPC
product
© 2011 ANSYS, Inc. February 24, 20127
Finite Arrays by Domain Decomposition• Each element in array treated as solution domain
• One compute engine can solve multiple elements/domains in series
Distributes element sub-domainsto networked processors and memory
© 2011 ANSYS, Inc. February 24, 20128
Example: Skewed Waveguide Array
• 16X16 (256 elements and excitations)
• Skewed Rectangular Waveguide (WR90) Array– 1.3M Matrix Size
• Using 8 cores– 3 hrs. solution time– 0.4GB Memory total
• Using 16 cores– 2 hrs. solution time– 0.8GB Memory total
• Additional Cores– Faster solution time– More memory.
Unit cell shown with wireframe view of virtual array
© 2011 ANSYS, Inc. February 24, 20129
Skewed Waveguide Array
• Patterns from 8X8 Array– Dashed is
idealized infinite array analysis
– Solid from finite array analysis
• Two simulations use identical mesh
• Note edge effects due to finite array size
© 2011 ANSYS, Inc. February 24, 201210
Efficient: 8X8 Array Patch Array
Direct solver with 12 cores
•5:05:14•60.8 GB RAM
Finite Array with 12 cores
•00:44:53•1.8 GB
© 2011 ANSYS, Inc. February 24, 201211
Hybrid Finite Element‐Integral Equation Method
Finite Elements vs. Integral Equations
• Integral Equation Based Method– HFSS‐IE– Efficient solution technique for
open radiation and scattering– Surface only mesh and current
solution
Airbox not needed to model free space radiation
Airbox required to model free space radiation
• Finite Element Based Method– HFSS
– Efficient handle complex materialand geometries
– Volume based mesh and field solutions
This Finite Element-Boundary Integral hybrid method leverages the advantages of both methods to achieve the most accurate and robust solution for radiating and scattering problems
Conformal radiation volume with Integral Equations
© 2011 ANSYS, Inc. February 24, 201212
HFSS Hybrid Solving• Hybrid Solving introduced in HFSS 13 with FEBI– A highly accurate solution for open boundary problems
• Accurate: Solves directly for equivalent surface currents on boundary conditions • Efficient: Conformal arbitrary shape BC to reduce FEM solution domain• Reflectionless: can be placed closed to radiating surface. • Does not have to be continuous: provides possibility of physically separate FEM volumes
© 2011 ANSYS, Inc. February 24, 201213
HFSS Hybrid Solving – IE Regions
• Parallelized– IE regions
solved in parallel.
– Analogous to FEM domains
• Rigorous– Multiple
reflection
• Automated
© 2011 ANSYS, Inc. February 24, 201214
IE Dielectric Regions• Solve “large homogeneous blocks of dielectric” with a “boundary condition”– Replace enclosed arbitrary dielectrics– Solve with multiple open or enclosed IE regions– Conducting IE regions may be inside dielectric IE regions
FEM
Conducting IE
Enclosed IE
Ground Penetrating RadarAntenna
Air
Surface
Soil
Mine
Different solution domains may be solved in parallel with DDM
© 2011 ANSYS, Inc. February 24, 201215
HFSS‐IE POAsymptotic solver for extremely large
problems• In HFSS‐IE• Solves electrically huge problems• Currents are approximated in illuminated regions– Set to zero in shadow regions
• No ray tracing or multiple “bounces”
Target applications:• Large reflector antennas• RCS of large objects such as satellites
Option in solution setup for HFSS‐IE.Sourced by incident wave excitations• Plane waves or linked HFSS designs as a source
© 2011 ANSYS, Inc. February 24, 201216
PO Solver in HFSS-IE 14
• PO assumes the fields on all illuminated surface are the incident fields
• Effects of the scatterers are included by assuming the incident fields are scattered at each point on the body as if it were reflected from an infinite tangent plane at that point; J~2(n x Hinc ) for PEC.
• For non-illuminated surfaces the J are set to zero.
Where: JPO = 2(n x Hinc )
PEC
© 2011 ANSYS, Inc. February 24, 201217
PO Examples
Notice the shadowing of the gun barrel on the tank and the tank on the ground.
© 2011 ANSYS, Inc. February 24, 201218
HFSS‐IE PO ‐ Example
Offset reflector 50 λ0 in diameter fed by a horn HFSS far field link
Simulated with 8 coresIE: 48.3min and 11.9GBPO: 23S and 286MBNote > 120x speedup
© 2011 ANSYS, Inc. February 24, 201219
Huray Surface Roughness Model
• Realistic loss model for rough conductor surfaces
© 2011 ANSYS, Inc. February 24, 201220
Save Radiated Field Data Only• Reduces the amount of data stored on hard drive for large antenna problems• Setting in Solution Setup, Advanced Tab: discrete and fast sweeps
~10X Reduction
© 2011 ANSYS, Inc. February 24, 201221
Import List Entry for Edit Sources
Easy input for magnitude and phase from source list• Can include parametric variables
© 2011 ANSYS, Inc. February 24, 201222
Interpolating Sweep Passivity
• Interpolating sweep algorithm can check for passivity during the sweep and solve at any interpolated points found to be nonpassive
© 2011 ANSYS, Inc. February 24, 201223
Show Nets
“Show Nets” identifies 3D conducting paths between terminals
© 2011 ANSYS, Inc. February 24, 201224
DesignerVersion 7
© 2011 ANSYS, Inc. February 24, 201225
Designer Overview• Parameterized padstacks• Automated causal material• Multi‐frequency point adapting• Integrated 2D/3D views• Huray surface roughness models• Lumped Port De‐embedding• Trapezoidal trace cross‐sections• Automated Virtuoso HFSS Design• Passivity enforced interpolation• HFSS Solves from within Cadence• User‐defined outputs• IBIS AMI enhancements
© 2011 ANSYS, Inc. February 24, 201226
• Set up project within 2D layout environment of Designer– Layers, vias, PCB‐oriented geometry primitives– Easy port creation
• Simulate with the 3D HFSS engine
HFSS Solver‐on‐Demand in Designer
© 2011 ANSYS, Inc. February 24, 201227
Parameterized Padstacks
Enables parametric investigation of via geometry, or optimization.
Applied to global padstack definition. Therefore, project variables are used:
© 2011 ANSYS, Inc. February 24, 201228
Parameterized Differential Vias
© 2011 ANSYS, Inc. February 24, 201229
Layout Editor Enhancements
ParameterizableEtch Factor
Parameterizable Surface Roughness
Automatic Causal Djordjevic Sarkar Dielectric Models
© 2011 ANSYS, Inc. February 24, 201230
HFSS Setup & Solve Within Cadence
• Create and Solvemodels with HFSS from within Cadence Allegro, APD, & SiP
HFSS Solution Progress
© 2011 ANSYS, Inc. February 24, 201231
• Also…
DDR2/3 Timing Specifications
Information source: JEDEC specification JESD79-3
© 2011 ANSYS, Inc. February 24, 201232
User‐Defined Outputs
• UDO’s are a way of calling Python scripts from within the Designer GUI— Python is an intuitive and
powerful scripting language with a large scientific and engineering user base
• Perform custom analyses on simulation waveforms— A Python script can be
written to arbitrarily post‐process waveforms
© 2011 ANSYS, Inc. February 24, 201233
Creating a UDO‐based Report
• Once a UDO is set up, its results can be accessed like an ordinary output
© 2011 ANSYS, Inc. February 24, 201234
DDR3 Calculations With UDO
• Voltage and timing margins can be printed in Data Table format within the Designer GUI
© 2011 ANSYS, Inc. February 24, 201235
Macro‐Modeling with Network Data Explorer
Touchstone Models from Arbitrary Source can be converted to Multiple Model Types with Causality and Passivity Enforcement!
Advanced features
New!
© 2011 ANSYS, Inc. February 24, 201236
High Speed Serial Design with IBIS‐AMI
• Automated IBIS‐AMI Importing– IBIS‐AMI Specification Testing
• Pass/Fail• Advanced
© 2011 ANSYS, Inc. February 24, 201237
User Defined Transmit Jitter for HSS Design
PDF vs. timedefined in a text file
No jitter
Contents of text file userdefined.txt
© 2011 ANSYS, Inc. February 24, 201238
SIwaveVersion 6
© 2011 ANSYS, Inc. February 24, 201239
Signal Net Analyzer• Ideal and non‐ideal lumped parameters (i.e Zo)• Nexxim and HSPICE RLC simulations
Via to Via Coupling• Differential pair accuracy improvements
Solver Support for Arbitrary Antipad Cutouts• Improvement in via modeling accuracy
SYZ Solver Improvements• Guaranteed passive/causal SYZ solutions
FWS Improvements for Large Port Count Devices• Faster convergence and reduced RAM when using “Iterated
Fitting of Passivity” for large port count devices
Improved “Push Excitation” Accuracy & Robustness• SIwave now forces required interpolation from Designer 7.0.
Improved Surface Roughness • Added Huray surface roughness model
PI Advisor Improvements• Genetic Algorithm supports weighting of constraints• Genetic Algorithm supports new constraints
– Maximum Total Capacitor Area– Maximum Number of Capacitor Types
Improved SYZ Storage Architecture• 6x reduction in disk space for SYZ parameters
Solver
Memory and High Speed Serial Improvements
64 bit GUI for Windows
Table Impedance Calculator• Flight time plots• Transient Simulations with Nexxim or HSPICE
PKG & PCB Automation• Graphical selection & merging
Pin Grouping Automation• Multi‐part select with group per part/net definitions
Improved Validation Checker• Detection of pins belonging to multiple pin groups
Automated DCIR Reports
Equipotential Pads for DCIR Solver
Temperature Profile Plotting from Icepak
Improved Surface Roughness• Addition of Huray model in GUI
PI Advisor Improvements• Allowance of weighting constraints in GUI• Additional constraints added
– Maximum Total Capacitor Area– Maximum Number of Capacitor Types
Improved ODB++ Support
Support for X2Y Low Inductance Capacitors
GUI
© 2011 ANSYS, Inc. February 24, 201240
Via Enhancements
Improved handling of complex via antipad geometry Capture of direct via‐to‐via coupling
© 2011 ANSYS, Inc. February 24, 201241
Huray Surface Roughness
© 2011 ANSYS, Inc. February 24, 201242
DDR3 Solutions: Signal Net Analyzer
• Displays Z0, length, time delay, and reference layer• All possible paths (from each pin to every other pin on net) are displayed
– Sorted in descending order of path distance• User can click on an individual path in the table
– Variation in Z0 is graphically displayed– Path is highlighted in SIwave’s main layout window
• Ideal reference layer mode (default)– Traces on top & bottom metal layers are assumed to be microstrips– Interior traces are assumed to be striplines
• Non‐ideal reference layer mode– Reference layer is explicitly calculated for each trace segment– Some traces may be floating (no suitable reference layer available)
© 2011 ANSYS, Inc. February 24, 201243
Automated DCIR Reporting• Automatically generate a formatted report for DC IR drop simulations
© 2011 ANSYS, Inc. February 24, 201244
Equipotential Pads for DCIR
Power Density Plot: Without Pad Power Density Plot: With Pad
Current Density Plot: Without Pad Current Density Plot: With Pad
© 2011 ANSYS, Inc. February 24, 201245
Q3DVersion 11
© 2011 ANSYS, Inc. February 24, 201246
Q3D Extractor Overview
Major Applications• 64 Bit Windows GUI• Magnetic Materials • Terminal Setup Improvements for AC RL Solver• Touch Panel Expression Caching for CG and RL• Selectable Frequency Export for Lumped SPICE Passives• DCRL Speed Up• CG Convergence improvements• HPC Improvements– Network Installs– Fixed Variables
• Greatly improves post processing speed for projects with large numbers of variables– i.e. Via Wizard
• 3D Modeling Enhancements• WB Integration Improvements for DSO & Optimetrics
© 2011 ANSYS, Inc. February 24, 201247
Touch Screen Accuracy Improvements
• Added the ability to converge on off diagonal terms with Touch Panel displays
© 2011 ANSYS, Inc. February 24, 201248
Magnetic Materials
Q3D AC 10 s Maxwell 3D 50 minQ3D DC 6min 30 sSweep 2 s
Total < 7 min 50 minPeak RAM 0.6 GB 5 GB
Simulation Time
Electroplated Nickel has 5Bulk Nickel has 600
© 2011 ANSYS, Inc. February 24, 201249
3D Modeler Enhancements
View customization.
• Z-stretch.• 64‐bit user interface