Learning Forum

[prince.mathew]

Hello everyone,

I’m currently working on a project where I need to simulate the radiated emissions of a PCB using Ansys HFSS, and I would really appreciate some guidance on the correct workflow and best practices.

Background

• I have designed my PCB using KiCAD PCB Designer
• The board includes both passive components (R, L, C) and active components (ICs, drivers, etc.)
• My goal is to analyze radiated emissions (EMI/EMC) from the PCB

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What I Want to Achieve

1. Import my PCB layout and geometry (traces, vias, stack-up) from KiCAD into HFSS
2. Include component footprints and relevant electrical characteristics
3. Properly define:
   • Excitations (ports, sources for active components)
   • Material properties
   • Radiation boundary / air region
4. Perform radiated emissions simulation (far-field / near-field)
5. Evaluate EMI behavior from both:
   • Passive structures (traces, planes, vias)
   • Active sources (switching ICs, signal drivers)

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Current Challenges

I’m currently stuck in the following areas:

• KiCAD → HFSS workflow

  • What is the best export format? (STEP, IDF, IPC-2581, ODB++, etc.)
  • How to preserve PCB stack-up and copper layers correctly?

• Component Modeling

  • How to treat passive vs active components in HFSS?
  • Should I:
    • Use lumped elements?
    • Replace ICs with equivalent sources?
    • Import full 3D models?

• Excitation Setup

  • How to define realistic excitation for EMI simulation?
  • Especially for digital/high-speed switching signals

• Simulation Setup

  • Best practices for:
    • Radiation boundary setup
    • Mesh refinement for EMI problems
    • Frequency range selection

• Tools & Workflow

  • Should I be using:
    • HFSS 3D Layout instead of HFSS 3D
    • SIwave or Electronics Desktop workflow
    • Any specific Ansys PCB import tools?

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What I’m Looking For

I would really appreciate:

• A step-by-step workflow for going from KiCAD → HFSS
• Recommendations on which Ansys tool/module is most suitable (HFSS vs HFSS 3D Layout vs SIwave)
• Best practices for EMI/radiated emissions simulations of PCBs
• Any tutorials, examples, or documentation relevant to this use case

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Additional Context

I’m relatively new to HFSS and EMC simulations, so even high-level guidance on the correct approach and toolchain would be extremely helpful.

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Thank you in advance for your time and support!
I’m looking forward to your suggestions and insights.