Introduction to High Frequency Structure

Simulator

Pengcheng Jia

Background Introduced from 90s Simulation tool for complex 3 D

geometries Using Finite Element Method Adaptive Mesh generation & refinement 2 Main Vendors—Agilent & Ansoft Merger from May 1 Transfer to Ansoft HFSS after Nov. 1,

2001

Requirement & Resources HFSS consume tremendous memory if

fine result is needed 300M+ Memory and 400M+ processor

is recommended Floating License Key within ECEWIN2K

subnet Remote access to new Scully which

has 1 G RAMBUS400 Memory and 1.7G P4 processor

Agilent HFSS

Ansoft HFSS

Features(1) Computes s-parameters and full-wave Computes s-parameters and full-wave

fields for arbitrarily-shaped 3D passive fields for arbitrarily-shaped 3D passive structuresstructures

Powerful drawing capabilities to simplify Powerful drawing capabilities to simplify design entrydesign entry

Field solving engine with accuracy-driven Field solving engine with accuracy-driven adaptive solutionsadaptive solutions

Powerful post-processor for unprecedented Powerful post-processor for unprecedented insight into electrical performanceinsight into electrical performance

Features(2) Advanced materialsAdvanced materials Model Library-including spiral Model Library-including spiral

inductorsinductors Model half, quarter, or octet symmetry Model half, quarter, or octet symmetry Calculate far-field patternsCalculate far-field patterns Wideband fast frequency sweepWideband fast frequency sweep Create parameterized cross section Create parameterized cross section

models- 2D modelsmodels- 2D models

Applications Antennas Microwave transitions Waveguide components RF filters Three-dimensional discontinuities Passive circuit elements

Procedure to simulate

1. Open or Make new project2. Draw objects3. Assign material property4. Define boundary conditions5. Solve6. Display result

New project

Project Preferences

Drawing basics

Drawing Lines & 2 D objects

Drawing 3 D objects

Object Library

Editing Objects

Materials

Metal & Resistor

Boundaries

Boundary Conditions

Add A Boundary

Display Boundary

Calibrating Ports

Solve

Frequency & Meshing

Displaying Results

S Matrix

Plot Field

Result Comparison r=8.5; Hsub=625 um; W=150um; G=75 um

@10G Theoretical

HFSS

L=100 um

0.04 nH 0.05 nH

L=300 um

0.12 nH 0.13 nH

L=600 um

0.24 nH 0.24 nH

L=800 um

0.33 nH 0.31 nH

00

0

L

L

Z jZ Tan LZ Z

Z jZ Tan L

---Theoretical Equation

Finite Element Method

Tetrahedron

Impedance Concept Zpi, Zpv & Zvi Microstrips use Zpi impedance

Slot-type (CPW) use Zpv impedance

TEM waves use Zvi impedance

*

2 1; ;

2

PZpi P ExHds I Hdl

I I

*

2

V VZpv

P

Zvi Zpi Zpv

Projects with HFSS Microstrip Line to Waveguide Transition

EM Field of the transition

Waveguide Combiner System

Slotline Antenna

Bonding Wire Discontinuity

Packaging for CPW Lines

Field Plot

Useful links http://www.ansoft.com http://dutettq.et.tudelft.nl/~hfss/welcome.ht

ml http://wwwinfo.cern.ch/ce/ae/Maxwell/index.

html

Documents for HP HFSS is in “Scully” c:/Otherprg/hfss/doc

References HP High-Frequency Structure

Simulator User’s Reference HP High-Frequency Structure

Simulator Tutorial