1 Family Tree of Antennas David Conn VE3KL Acknowledgements Acknowledgements Doug Leach VE3XK Doug...

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Family Tree of AntennasFamily Tree of AntennasDavid ConnDavid Conn VE3KL VE3KL

• AcknowledgementsAcknowledgements • Doug Leach VE3XKDoug Leach VE3XK• Bert Barry VE3QAABert Barry VE3QAA• QCWA MembersQCWA Members• The InventorsThe Inventors• References given in References given in

slidesslides• ARRL Antenna bookARRL Antenna book

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Why Make a Family TreeWhy Make a Family Tree

• To understand the overall (complex) To understand the overall (complex) picturepicture

• To enable us to select a good antennaTo enable us to select a good antenna

• To organize and compare existing To organize and compare existing designsdesigns Antenna Types

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Antenna Types 1…6Antenna Types 1…6

1.1. Resonant Wires: Dipole, Yagi, Quad, Resonant Wires: Dipole, Yagi, Quad, Vertical, Moxon Square ……. Vertical, Moxon Square …….

2.2. Long wires (non-resonant): Zepp/G5RV…Long wires (non-resonant): Zepp/G5RV…

3.3. Resistively Loaded: Beverage, Pennant, Resistively Loaded: Beverage, Pennant, Rhombic …Rhombic …

4.4. Small Loops/Wires: Resonant Loading Small Loops/Wires: Resonant Loading CircuitsCircuits

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Antenna Types 1…6Antenna Types 1…6

5.5. Phased Arrays: Yagi, Collinear, Sterba Phased Arrays: Yagi, Collinear, Sterba Curtain, Rhombic, Four Element Curtain, Rhombic, Four Element Rectangular Array, Many Others …Rectangular Array, Many Others …

6.6. Lens Antennas for UHF/Microwaves: Lens Antennas for UHF/Microwaves: Parabolic Dish, HelixParabolic Dish, Helix … …

Family Tree

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Amateur Radio

Antennas(index)

RadiationWavesCircuits

Ground/IonosphereTransmission Lines

Simulation/Smith Chart

Receiving AntennasSNR

HFUHF/VHFMF

Microwave

Transmitting AntennasPower

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Transmitting AntennasTransmitting Antennas

• Performance measured by Gain & Performance measured by Gain & Directivity Directivity

• Low Loss: Transmitter MatchingLow Loss: Transmitter Matching

• SWR of 2:1 loses half the powerSWR of 2:1 loses half the power

• Ground/Ionosphere… dominates Ground/Ionosphere… dominates

• Polarization (Vertical for MF Transmitters)Polarization (Vertical for MF Transmitters)

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Receiving Antennas…SNRReceiving Antennas…SNR

• Performance measured by RDF (dB)Performance measured by RDF (dB)

• RDF (Receiving Directivity Factor) defined RDF (Receiving Directivity Factor) defined as peak response in desired direction to as peak response in desired direction to average response in all directions average response in all directions

• Ground/Ionosphere… extremely importantGround/Ionosphere… extremely important

• Consider Polarization: VHF weak signal Consider Polarization: VHF weak signal (DX) uses Horizontal Polarization(DX) uses Horizontal Polarization

Antenna ExamplesAntenna Examples

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MF AntennasMF AntennasNeed good S/N…not Gain for ReceiveNeed good S/N…not Gain for Receive

• Inverted L, TInverted L, T• Beverage Antenna… the best?Beverage Antenna… the best?• Terminated loops (Pennant, Flag)Terminated loops (Pennant, Flag)• Vertical Phased ArraysVertical Phased Arrays• Vertical GP antennasVertical GP antennas• K9AY LoopK9AY Loop• 4 Square Vertical4 Square Vertical

Green indicates Receive Only AntennaGreen indicates Receive Only Antenna

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Inverted L,T,Vertical,K9AY AntennasInverted L,T,Vertical,K9AY Antennashttp://www.antennex.com/preview/archive3/ltv.htmhttp://www.antennex.com/preview/archive3/ltv.htm

http://www.aytechnologies.com/TechData/LoopInstall.htmhttp://www.aytechnologies.com/TechData/LoopInstall.htm

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MF Receiving Antenna PerformanceMF Receiving Antenna Performance

RDF, dB

Cost

Good

Bad

8.64

Beverage 1.0 W

Vertical Omni

2 Broadside Beverages 1.75 W

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Flag/Pennant

5.0

Small 4X4 Square

80 m high

Beverage 0.5 W

Vertical phased array B/S

Low Dipole

K9AYDipole

http://www.w8ji.com/antennas.htm

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Classic Dipole: type 1 .. Elevation Classic Dipole: type 1 .. Elevation PlotPlot

35 feet

RDF = 8.3 dB Good

Ground

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Classic Dipole: type 1 .. Azimuth PlotClassic Dipole: type 1 .. Azimuth Plot

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Classic Vertical Ground Plane: type 1Classic Vertical Ground Plane: type 1

RDF =5 dB

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Two Element Quad…Azimuth: type 1Two Element Quad…Azimuth: type 1

31 feet high to

top

RDF = 12.84 dB…high

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End Fed Zepp Antenna: type 2End Fed Zepp Antenna: type 2

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MF Pennant…Receive only: type 3MF Pennant…Receive only: type 3

• Ground independentGround independent• Very Low Gain (-35 Very Low Gain (-35

dB)dB)• RDF = 7.39 dB…OKRDF = 7.39 dB…OK• Cardoid patternCardoid pattern• F/B 25 dBF/B 25 dB• Small..20 feet each Small..20 feet each

armarm• Terminated loop classTerminated loop class

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Small Magnetic Loop Antenna: type 4Small Magnetic Loop Antenna: type 4Very High VoltagesVery High Voltages

g3ycc.karoo.net/loop.htm

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Microwave Antenna Array: type 5 & 6Microwave Antenna Array: type 5 & 6Space DiversitySpace Diversity

Transmitter ReceiversWanted Rays

Unwanted Rays

Arrays

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Arrays Arrays

►Driven arraysDriven arrays: Collinear, Sterba and : Collinear, Sterba and Bobtail Curtains, two dimensional Bobtail Curtains, two dimensional arrays, three dimensional (lens) arrays, three dimensional (lens) arrays, Log Periodicarrays, Log Periodic

End fire or broadside or End fire or broadside or anyany beam shape beam shape

►Parasitic arraysParasitic arrays: Yagi: Yagi

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Linear Arrays (Driven)Linear Arrays (Driven)Directivity increases with LengthDirectivity increases with Length

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Four Element Rectangle.. Easy to Four Element Rectangle.. Easy to VisualizeVisualize

ARRL Antenna Book

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Collinear ArraysCollinear Arrays

http://www.tpub.com/neets/book10/42i.htm

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Bobtail Curtain Driven ArrayBobtail Curtain Driven ArrayMaximum Gain 4.5 dBiMaximum Gain 4.5 dBiLow Angle RadiationLow Angle Radiation

ARRL Antenna Book

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Log Periodic Antenna Array…looks like a Log Periodic Antenna Array…looks like a tapered Yagi but each element is driventapered Yagi but each element is driven

► Very Broad BandVery Broad Band► Dimensions repeat Dimensions repeat

logarithmicallylogarithmically► QST Sept. 2002QST Sept. 2002

ARRL Antenna BookARRL Antenna Book

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VHF/UHF/Microwave AntennasVHF/UHF/Microwave Antennas

• Yagi, Quagi, Quads ….stacked versionsYagi, Quagi, Quads ….stacked versions• Cycloid Dipole…Cycloid Dipole…

Circular Polarization..RepeatersCircular Polarization..Repeaters• Helix and Helix ArraysHelix and Helix Arrays• Vertical, JpoleVertical, Jpole• Corner Reflectors, Parabolas, LensesCorner Reflectors, Parabolas, Lenses• Circuit board patch antenna arraysCircuit board patch antenna arrays

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The J Pole Antenna: type 1The J Pole Antenna: type 1

• Easy to BuildEasy to Build• No ground plane No ground plane

neededneeded• Many designs Many designs

availableavailable

http://www.cebik.com/jp2.html

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Cycloid DipoleCycloid DipoleCircular Polarization…Repeaters: type 1Circular Polarization…Repeaters: type 1

http://www.wa7x.com/cycloid_info.html

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SummarySummary

• Tree must include antenna design as well as Tree must include antenna design as well as the physical description the physical description

• Tree must include: ground effects, basics of Tree must include: ground effects, basics of the ionospherethe ionosphere

• Tree must link to the most important well Tree must link to the most important well proven designsproven designs

• Tree must help amateurs at all levels to Tree must help amateurs at all levels to select an appropriate antennaselect an appropriate antenna

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Many Thanks: Especially to the Many Thanks: Especially to the OrganizersOrganizers

http://www.dxlc.com/solar/