Family Tree of Antennas David Conn VE3KL

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Family Tree of AntennasDavid Conn VE3KL

• Acknowledgements

• Doug Leach VE3XK
• Bert Barry VE3QAA
• QCWA Members
• The Inventors
• References given in slides
• ARRL Antenna book

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Why Make a Family Tree

• To understand the overall (complex) picture
• To enable us to select a good antenna
• To organize and compare existing designs

Antenna Types
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Antenna Types 16

• Resonant Wires Dipole, Yagi, Quad, Vertical,
  Moxon Square .
• Long wires (non-resonant) Zepp/G5RV
• Resistively Loaded Beverage, Pennant,
  Rhombic
• Small Loops/Wires Resonant Loading Circuits

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Antenna Types 16

• 5. Phased Arrays Yagi, Collinear, Sterba
  Curtain, Rhombic, Four Element Rectangular Array,
  Many Others
• Lens Antennas for UHF/Microwaves Parabolic
  Dish, Helix

Family Tree
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Radiation Waves Circuits
Transmission Lines
Ground/Ionosphere
Receiving Antennas SNR
Transmitting Antennas Power
Amateur Radio Antennas (index)
Simulation/Smith Chart
Microwave

UHF/VHF
MF
HF
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Transmitting Antennas

• Performance measured by Gain Directivity
• Low Loss Transmitter Matching
• SWR of 21 loses half the power
• Ground/Ionosphere dominates
• Polarization (Vertical for MF Transmitters)

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Receiving AntennasSNR

• Performance measured by RDF (dB)
• RDF (Receiving Directivity Factor) defined as
  peak response in desired direction to average
  response in all directions
• Ground/Ionosphere extremely important
• Consider Polarization VHF weak signal (DX) uses
  Horizontal Polarization

Antenna Examples
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MF AntennasNeed good S/Nnot Gain for Receive

• Inverted L, T
• Beverage Antenna the best?
• Terminated loops (Pennant, Flag)
• Vertical Phased Arrays
• Vertical GP antennas
• K9AY Loop
• 4 Square Vertical
• Green indicates Receive Only Antenna

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Inverted L,T,Vertical,K9AY Antennas
http//www.antennex.com/preview/archive3/ltv.htm
http//www.aytechnologies.com/TechData/LoopInstall
.htm
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MF Receiving Antenna Performance
RDF, dB
Vertical phased array B/S
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2 Broadside Beverages 1.75 W
Good
Beverage 1.0 W
8.64
Small 4X4 Square
Dipole
Flag/Pennant
K9AY
80 m high
Vertical Omni
Beverage 0.5 W
Bad
5.0
Cost
Low Dipole
http//www.w8ji.com/antennas.htm
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Classic Dipole type 1 .. Elevation Plot
35 feet
Ground
RDF 8.3 dB Good
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Classic Dipole type 1 .. Azimuth Plot
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Classic Vertical Ground Plane type 1
RDF 5 dB
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Two Element QuadAzimuth type 1
RDF 12.84 dBhigh
31 feet high to top
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End Fed Zepp Antenna type 2
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MF PennantReceive only type 3

• Ground independent
• Very Low Gain (-35 dB)
• RDF 7.39 dBOK
• Cardoid pattern
• F/B 25 dB
• Small..20 feet each arm
• Terminated loop class

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Small Magnetic Loop Antenna type 4Very High
Voltages
http//www. g3ycc.karoo.net/loop.htm
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Microwave Antenna Array type 5 6Space
Diversity
Transmitter
Receivers
Wanted Rays
Unwanted Rays
Arrays
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Arrays Antennas

• Driven arrays Collinear, Sterba and Bobtail
  Curtains, two dimensional arrays, three
  dimensional (lens) arrays, Log Periodic
• End fire or broadside or any beam shape
• Parasitic arrays Yagi

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Linear Arrays (Driven)Directivity increases with
Length
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Four Element Rectangle.. Easy to Visualize
ARRL Antenna Book
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Collinear Arrays
http//www.tpub.com/neets/book10/42i.htm
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Bobtail Curtain Driven ArrayMaximum Gain 4.5
dBiLow Angle Radiation
ARRL Antenna Book
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Log Periodic Antenna Arraylooks like a tapered
Yagi but each element is driven

• Very Broad Band
• Dimensions repeat logarithmically
• QST Sept. 2002

ARRL Antenna Book
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VHF/UHF/Microwave Antennas

• Yagi, Quagi, Quads .stacked versions
• Cycloid Dipole
• Circular Polarization..Repeaters
• Helix and Helix Arrays
• Vertical, Jpole
• Corner Reflectors, Parabolas, Lenses
• Circuit board patch antenna arrays

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The J Pole Antenna type 1

• Easy to Build
• No ground plane needed
• Many designs available

http//www.cebik.com/jp2.html
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Cycloid DipoleCircular PolarizationRepeaters
type 1
http//www.wa7x.com/cycloid_info.html
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Summary

• Tree must include antenna design as well as the
  physical description
• Tree must include ground effects, basics of the
  ionosphere
• Tree must link to the most important well proven
  designs
• Tree must help amateurs at all levels to select
  an appropriate antenna

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Many Thanks Especially to the Organizers
http//www.dxlc.com/solar/