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Antennas -- in 50 Minutes or Less!. Cynthia Furse Department of Electrical and Computer Engineering Utah State University furse@ece.usu.edu. Introduction to Antennas. Antenna Parameters Types of Antennas Where to find out more. Antenna Parameters. Radiation Pattern Directivity Gain
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Antennas -- in 50 Minutes or Less! Cynthia Furse Department of Electrical and Computer Engineering Utah State University furse@ece.usu.edu
Introduction to Antennas • Antenna Parameters • Types of Antennas • Where to find out more
Antenna Parameters • Radiation Pattern • Directivity • Gain • Planes ( E or H, Elevation or Azimuth) • Lobes (HPBW, FSLBW, etc.) • Input Impedance • Link Budget
Common Types of Antennas • Wire Antennas • Dipoles, Monopoles, Monopoles above Gnd • Patch, Printed circuit board antennas • Slots, apertures • Dishes, Reflector Antennas • Arrays
Dipole Antenna From:http://www.qth.com/antenna/dipole.gif,plot.gif
Folded Dipole From:http://www.qth.com/antenna/fdipole.gif
Monopole Antenna From: http://www.letstalk.com//Images/mits-ah-129.GIF
Monopole Antenna From:http://www.letstalk.com//Images/5-a.gif
The University of Utah mm-resolution Head Model Furse, Lazzi, Gandhi, “FDTD Computation of Power Deposition in the Head for Cellular Telephones,” Proc. 1996 IEEE APS Symposium
Applications: Cellular Telephones SAR Distribution in Adult - 835 MHz - Simplified Phone Model - l /4 antenna Pandit,McDermott,Lazzi,Furse,Gandhi, “Electrical Energy Absorption in the Human Head,” presented at IEEE Visualization ‘96, S.F., CA 1996
SAR Distributions - 835 MHz (adult, 10 year old, 5 year old) 10 year old Adult 5 year old From: Gandhi, Lazzi, Furse, IEEE Trans. MTT 44(10) 1996
V-Antenna v.gif From:http://www.qth.com/antenna/v.gif
Loop Antenna From:http://www.downeastmicrowave.com/graphics/kbloop.gif
Pagers From: http://www.letstalk.com//Images/13-a.gif
Discone Antenna From: http://www.northcountryradio.com/discfig.htm
Reflector (Dish) Antenna From: http://www.dssdirectv.com/chanmas1.jpg
Arecibo Observatory -- Puerto Rico From: http://www.naic.edu/about/photos/aoviews/tescop.jpg
Arecibo Observatory From:http://www.naic.edu/about/photos/aoviews/wideao.jpg
Arecibo Observatory From: http://www.naic.edu/about/photos/aoviews/tescop4.jpg
Horn Antennas From: http://www.tmo.hp.com/tmo/datasheets/Images/img-HP11966J-1lg.gif
Conical Horn Antenna From: http://www.afcsat.com/CH14_MOT2.jpg
GPS Antennas From:http://www.lowe.co.uk/gpsant.jpg
GPS Antenna SEN 67157549 SENSOR SYSTEMS L1 From:http://gracie.grdl.noaa.gov/GRD/GPS/Projects/ANTCAL/Models/Images/SENS67157549.s.jpg
GPS Antenna with Choke Ring SEN 67157549+cr SENSOR SYSTEMS L1 WITH CHOKE RING From:http://gracie.grdl.noaa.gov/GRD/GPS/Projects/ANTCAL/Models/Images/SENS671575+cr.s.jpg
GPS Antenna LEI AT302 From:http://gracie.grdl.noaa.gov/GRD/GPS/Projects/ANTCAL/Models/LEI_AT302.shtml
Antenna Arrays Two Elements -- Pattern adds constructively or destructively From: http://server5550.itd.nrl.navy.mil/projects/HAARP/images/ant/pat1.gif
Antenna Arrays More Elements: Higher Directivity Sidelobes From: http://server5550.itd.nrl.navy.mil/projects/HAARP/images/ant/pat2.gif
Scanning Antenna Array Changing the phases on the element feeds can make a scanning array. From:http://server5550.itd.nrl.navy.mil/projects/HAARP/images/ant/pat3.gif
Arrays From:http://www.qth.com/antenna/tiny2rl.gif
Yagi-Uda Arrays From: http://cust.iamerica.net/dwhowell/yagimax.jpg
Satellite Antenna Array From:http://www.qth.com/antenna/hfsatrl.gif
HAARP Observatory HAARP (High frequency Active Auroral Research Program) is to be a major Arctic facility for upper atmospheric and solar-terrestrial research. HAARP is being built on a DoD-owned site near Gakona, Alaska. From:http://server5550.itd.nrl.navy.mil/projects/HAARP/images/ohd.jpg
HAARP Antenna Array The HF antenna system to be used for Active Ionospheric Research at the HAARP site will assist other facility instruments in the study the overhead ionosphere. As a result, it too has been designed to optimize or restrict the transmission pattern to lie within a narrow overhead region. To achieve this desirable antenna pattern, the HAARP system uses an "array" of individual antenna elements. The HAARP antenna array is similar or identical to many other types of directive antenna types in use for both military and civilian applications including air traffic control radar systems, long range surveillance systems, steerable communication systems and navigation systems. From:http://server5550.itd.nrl.navy.mil/projects/HAARP/images/twr/pan2.jpg
HAARP -- Feed Sytem From:http://server5550.itd.nrl.navy.mil/projects/ HAARP/images/ant/tpile.jpg
HAARP -- Matching Networks From: http://server5550.itd.nrl.navy.mil/projects/HAARP/images/ant/amu.jpg
Corner Reflector Antenna From: http://www.northcountryradio.com/crfigs.htm
Anything Radiates …Fan-tenna From:http://www.qth.com/antenna/fanfull.gif
The Bottom Line • ANYTHING radiates. Sometimes you want it to, and sometimes you don’t. • To choose an antenna for your design, prepare a LINK BUDGET to determine the necessary gain and directivity of your antenna. • Don’t forget MATCHING NETWORKS to prevent reflection between your antenna and your circuit.
Antenna References on the Web General: http://www.ee.surrey.ac.uk/Personal/D.Jefferies/antennas.html GPS Antennas Lowe Industries :http://www.lowe.co.uk/antrev2.htmlhttp://www.lowe.co.uk/antrev2.html Antenna Calibration: http://gracie.grdl.noaa.gov/GRD/GPS/Projects/ANTCAL/index.shtml Ham: North Country Radio: http://www.northcountryradio.com/techtips.htm Antenna Elmer: http://www.qth.com/antenna/antenna.htm HAARP Observatory: http://server5550.itd.nrl.navy.mil/projects/HAARP/ant3.html Arecibo Obervatory: http://www.naic.edu/aboutao.htm