Transcript Antenna Modeling software Ken Konechy W6HHC Antenna Modeling software • • • • • teaches you more about antennas how to design better antennas how to predict antenna performance how to “tune”

Antenna Modeling
software
Ken Konechy W6HHC
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Antenna Modeling
software
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teaches you more about antennas
how to design better antennas
how to predict antenna performance
how to “tune” for performance
lets you try “what if….”
Ken Konechy W6HHC
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“What is Antenna Modeling?”
• it is NOT making tiny models
• it is a computer program to predict and
analyze antenna performance
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“What is Antenna Modeling SW?”
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Allows you to describe an antenna
Allows you to describe your antenna height
Allows you to choose construction materials
Allows you to describe your ground conditions
Allows you to analyze gain
Allows you analyze impedance / SWR
Allows you to predict “band-width”
Allows you to plot directivity & front-to-back
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Example of an
Antenna Modeling Program
EZNEC Software Describing a 40M Inverted-Vee
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Another Example of an
Antenna Modeling Program
NEC-Win Describing a 10M 2-El Beam
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Example of an
Antenna Modeling Program
Select Material for a 10M Dipole
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Example of an
Antenna Modeling Program
• NO GROUND – “free space conditions”
• PERFECT GROUND – “ The perfect world is simulated”
• SOMMERFELD GROUND – “Choose many real conditions”
• REAL GROUND – “Complex, allows nearby cliffs, hills, etc.”
Select “ground conditions” for a 10M Dipole
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Example of an
Antenna Modeling Program
Select “Sommerfeld ground conditions”
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Example of an
Antenna Modeling Program
Gain plots for a 6-EL 20M Beam
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Example of an
Antenna Modeling Program
Predicting SWR for a 10M Dipole at 20ft
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Let us Explore a 10M Dipole
Gain plots for 10M Dipole over different grounds
Height = 20 ft
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Let us Explore a 10M Dipole
Gain plots for 10M Dipole at different heights
Over Sandy ground
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Let us Explore a 10M Dipole
Gain plots for 10M Dipole at 5 degree Elev
10.7 dB of the gain is lost at 5 degrees!!!!!!
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Let us Explore a 2-EL 10M Beam
Gain plots for 10M Beam at different heights
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Explore Antenna Model for 30M Dipole
“Shortened” 30M Dipole Design
(Four sections of Aluminum tubing)
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Antenna Model for 30M Dipole
I wanted mast for 30M Dipole only 10-ft high
(Horizontal dipole is a “cloud-warmer”)
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Antenna Model for 30M Dipole
Horiz Shortened-Dipole
Vert Shortened-Dipole
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Antenna Model for 30M Dipole
Finished Construction of 30M Shortened-Dipole
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Antenna Model for 1.2 GHz “Panel”
Six Loops of wire are positioned over a
Mesh Reflector for basic Panel Antenna
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Antenna Model for 1.2 GHz “Panel”
Two sets of Six-Loop Arrays provide 3 dB
More Gain for a Total of 17 dBd
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Antenna Model for 1.2 GHz “Panel”
Large 6-loop panel array by
HA5IW mounted up on the Tower
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Antenna Modeling – “a lesson learned”
• While preparing a TechTalk on Panel Antenna,
I corresponded with G8GML about gain
• In G8GML’s article in CQ-TV, he field tested
the 6-loop design over mesh at 16 dBd gain
• My NEC-Win model showed 14 dBd ??
• G8GML kindly explained “ground reflection” at
a test site can add to measured gain
• So in real world…“Your mileage may vary!”
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Different Antenna Modeling SW
• NEC2 – was designed by Lawrence Livermore Labs
• EZNEC - uses NEC2 “core” software with Windows GUI
- by Roy Lewallen, W7EL
- www.eznec.com
• NEC-Win – uses NEC2 “core” SW with GUI
- by L. B. Cebik, W4RNL (SK)
- NO LONGER SOLD
• MINI-NEC – simplified NEC2 to run on slow PCs
- fairly obsolete, inaccurate
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Antenna Modeling
software
The End
Any Questions??
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