presentation - broadband patch antennahibp.ecse.rpi.edu/~connor/education/antennas/ericsson.pdf ·...
TRANSCRIPT
Rev B EMW/FX/BE Daniel Byström2003-11-20 1
Broadband Patch Antenna
Daniel ByströmDesign by: Andreas Wikström
Ericsson Microwave Systems ABFX/BE Antenna and Microwave Design
Rev B EMW/FX/BE Daniel Byström2003-11-20 2
Contents
• Introduction• Prerequisites• Patch Design• Simulation Difficulties• Verification of the Design• Results
Rev B EMW/FX/BE Daniel Byström2003-11-20 3
Introduction
• Broadband antenna elements• Balanced feed• Simulated without balun
Rev B EMW/FX/BE Daniel Byström2003-11-20 4
Prerequisites
• 1 octave bandwidth• Frequency 1-2 GHz• Infinite array• Element spacing λ/2= 75*75mm (2GHz)• Stacked patch antenna• Balanced feed• Ideal 180° hybrid
Rev B EMW/FX/BE Daniel Byström2003-11-20 5
Basic Patch Design
• Dielectric puck• Balanced coaxial feed• Probe inductance compensation
Duroid
Roacell
Teflon
Jordplan Port 1 Port 2
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Modeling in Ansoft HFSS
• Perf_conductor• Master-/Slave-boundaries• Radiation boundary• PML-layer
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Ideal 180° Hybrid
)(5.0 2112,221111 ,antenna,antennaantenna,antenna,total SSSSS −−+=
• Hybrid calculated with MatLab
180°-hybrid Antenna
1
2
2
4
1
3
Unbalanced port
Termination
Rev B EMW/FX/BE Daniel Byström2003-11-20 8
Simulation Results
E-plane scanning H-plane scanning
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Difficulties
• Problems with radiation boundary for scanned examples• Results are very convergence sensitive when using an
ideal 180°-hybrid
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Array Simulator Principle
The reflections off the walls of the waveguide are used to make the element behave as though in an array.
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Array Simulator Model
• ½+1+½ elements are used• Only gives information about one scan-
angle for every frequency
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Comparing an Array Simulator and an Infinite Array
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Port Adaption
The measured and simulated ports have different impedances
• Coaxial port on patch is 84 Ω• Measured port is 50 Ω
Solution: simulate measured port
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Measured Results Compared to the Simulation
• Excellent match between measured and simulated results!