EMI Simulation in Multi-Radio Embedded Device

Project Description

We are looking for a freelancer with strong RF and simulation experience to analyze and optimize antenna coexistence and electromagnetic interference (EMI) shielding in a multi-radio embedded system.

The system includes 2.4 GHz Wi-Fi, GNSS, and LTE antennas integrated into a compact PCB within a plastic enclosure. The primary goal is to evaluate the isolation, mutual coupling, and radiated noise between the antenna elements and identify shielding strategies or layout improvements to improve overall performance.

Scope:

No physical prototyping required — simulation and design recommendations only.
The board size and antenna types are predefined; simulation model will be provided to the selected freelancer.

Objectives

• Evaluate mutual coupling (S12/S21) between antenna pairs
• Simulate radiation patterns when multiple antennas are active
• Analyze near-field and far-field EMI from onboard DC-DC converters and digital lines
• Suggest shielding strategies (e.g., ground fencing, absorber placement, component relocation)
• Recommend layout or placement changes to improve isolation
• Identify potential detuning risks under simultaneous TX conditions

Deliverables

• Annotated simulation project files (HFSS, CST, or equivalent)
• Graphs showing:
  • S11, S12, S21 vs frequency (1–3 GHz)
  • Isolation matrix between all antennas
  • 3D near-field EMI plot and far-field radiation pattern overlays
• 2–3 page report detailing:
  • Interference challenges
  • Suggested shielding improvements or layout changes
  • Trade-offs considered
  • Estimated benefit (in dB isolation or efficiency)

Suggested Tools

• CST Microwave Studio or ANSYS HFSS (preferred)
• Altair FEKO, EMPro, or COMSOL Multiphysics (if equipped for EMI/near-field analysis)
• Optional: MATLAB.

Ideal Candidate

• RF/microwave simulation expert with experience in multi-antenna systems
• Prior work with EMI/EMC simulations and system-level RF integration
• Familiarity with PCB layout issues in small embedded platforms
• Ability to document findings clearly with graphs and annotated visuals

Timeline

Duration: ~3 weeks
Week 1: Initial evaluation + mutual coupling analysis
Week 2–3: EMI analysis + shielding recommendations + report

How to Apply

Please include in your application:

• Your preferred EM simulation tool
• Sample EMI or coexistence study you’ve completed
• Any suggestions for evaluating coexistence performance or shielding
• Estimated total price and timeline