1 family tree of antennas david conn ve3kl acknowledgements acknowledgements doug leach ve3xk doug...
TRANSCRIPT
1
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
2
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
3
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
4
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
5
Amateur Radio
Antennas(index)
RadiationWavesCircuits
Ground/IonosphereTransmission Lines
Simulation/Smith Chart
Receiving AntennasSNR
HFUHF/VHFMF
Microwave
Transmitting AntennasPower
6
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)
7
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
8
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
9
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
10
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
13
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
11
Classic Dipole: type 1 .. Elevation Classic Dipole: type 1 .. Elevation PlotPlot
35 feet
RDF = 8.3 dB Good
Ground
12
Classic Dipole: type 1 .. Azimuth PlotClassic Dipole: type 1 .. Azimuth Plot
13
Classic Vertical Ground Plane: type 1Classic Vertical Ground Plane: type 1
RDF =5 dB
14
Two Element Quad…Azimuth: type 1Two Element Quad…Azimuth: type 1
31 feet high to
top
RDF = 12.84 dB…high
15
End Fed Zepp Antenna: type 2End Fed Zepp Antenna: type 2
16
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
17
Small Magnetic Loop Antenna: type 4Small Magnetic Loop Antenna: type 4Very High VoltagesVery High Voltages
g3ycc.karoo.net/loop.htm
18
Microwave Antenna Array: type 5 & 6Microwave Antenna Array: type 5 & 6Space DiversitySpace Diversity
Transmitter ReceiversWanted Rays
Unwanted Rays
Arrays
19
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
20
Linear Arrays (Driven)Linear Arrays (Driven)Directivity increases with LengthDirectivity increases with Length
21
Four Element Rectangle.. Easy to Four Element Rectangle.. Easy to VisualizeVisualize
ARRL Antenna Book
22
Collinear ArraysCollinear Arrays
http://www.tpub.com/neets/book10/42i.htm
23
Bobtail Curtain Driven ArrayBobtail Curtain Driven ArrayMaximum Gain 4.5 dBiMaximum Gain 4.5 dBiLow Angle RadiationLow Angle Radiation
ARRL Antenna Book
24
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
25
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
26
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
27
Cycloid DipoleCycloid DipoleCircular Polarization…Repeaters: type 1Circular Polarization…Repeaters: type 1
http://www.wa7x.com/cycloid_info.html
28
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
29
Many Thanks: Especially to the Many Thanks: Especially to the OrganizersOrganizers
http://www.dxlc.com/solar/