Antennas -- in 50 Minutes or Less!

1
Antennas -- in 50 Minutes or Less!

• Cynthia Furse
• Department of Electrical and Computer Engineering
• Utah State University
• furse_at_ece.usu.edu

2
Introduction to Antennas

• Antenna Parameters
• Types of Antennas
• Where to find out more

3
Antenna Parameters

• Radiation Pattern
• Directivity
• Gain
• Planes ( E or H, Elevation or Azimuth)
• Lobes (HPBW, FSLBW, etc.)
• Input Impedance
• Link Budget

4
(No Transcript)
5
Common Types of Antennas

• Wire Antennas
• Dipoles, Monopoles, Monopoles above Gnd
• Patch, Printed circuit board antennas
• Slots, apertures
• Dishes, Reflector Antennas
• Arrays

6
Dipole Antenna
Fromhttp//www.qth.com/antenna/dipole.gif,plot.gi
f
7
Folded Dipole
Fromhttp//www.qth.com/antenna/fdipole.gif
8
Monopole Antenna
From http//www.letstalk.com//Images/mits-ah-129.
GIF
9
Monopole Antenna
Fromhttp//www.letstalk.com//Images/5-a.gif
10
Monopole Antenna above Ground Dipole Antenna
11
V-Antenna
v.gif
Fromhttp//www.qth.com/antenna/v.gif
12
Loop Antenna
Fromhttp//www.downeastmicrowave.com/graphics/kbl
oop.gif
13
Pagers
From http//www.letstalk.com//Images/13-a.gif
14
Discone Antenna
From http//www.northcountryradio.com/discfig.htm
15
Reflector (Dish) Antenna
From http//www.dssdirectv.com/chanmas1.jpg
16
Arecibo Observatory -- Puerto Rico
From http//www.naic.edu/about/photos/aoviews/tes
cop.jpg
17
Arecibo Observatory
Fromhttp//www.naic.edu/about/photos/aoviews/wide
ao.jpg
18
Arecibo Observatory
From http//www.naic.edu/about/photos/aoviews/tes
cop4.jpg
19
Horn Antennas
From http//www.tmo.hp.com/tmo/datasheets/Images/
img-HP11966J-1lg.gif
20
Conical Horn Antenna
From http//www.afcsat.com/CH14_MOT2.jpg
21
GPS Antennas
Fromhttp//www.lowe.co.uk/gpsant.jpg
22
GPS Antenna
SEN 67157549 SENSOR SYSTEMS L1
Fromhttp//gracie.grdl.noaa.gov/GRD/GPS/Projects/
ANTCAL/Models/Images/SENS67157549.s.jpg
23
GPS Antenna with Choke Ring
SEN 67157549cr SENSOR
SYSTEMS L1 WITH CHOKE RING
Fromhttp//gracie.grdl.noaa.gov/GRD/GPS/Projects/
ANTCAL/Models/Images/SENS671575cr.s.jpg
24
GPS Antenna
LEI AT302
Fromhttp//gracie.grdl.noaa.gov/GRD/GPS/Projects/
ANTCAL/Models/LEI_AT302.shtml
25
Antenna Arrays
Two Elements -- Pattern adds constructively or
destructively
From http//server5550.itd.nrl.navy.mil/projects/
HAARP/images/ant/pat1.gif
26
Antenna Arrays
More Elements Higher Directivity Sidelobes
From http//server5550.itd.nrl.navy.mil/projects/
HAARP/images/ant/pat2.gif
27
Scanning Antenna Array
Changing the phases on the element feeds can make
a scanning array.
Fromhttp//server5550.itd.nrl.navy.mil/projects/H
AARP/images/ant/pat3.gif
28
Arrays
Fromhttp//www.qth.com/antenna/tiny2rl.gif
29
Yagi-Uda Arrays
From http//cust.iamerica.net/dwhowell/yagimax.jp
g
30
Satellite Antenna Array
Fromhttp//www.qth.com/antenna/hfsatrl.gif
31
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.
Fromhttp//server5550.itd.nrl.navy.mil/projects/H
AARP/images/ohd.jpg
32
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.
Fromhttp//server5550.itd.nrl.navy.mil/projects/H
AARP/images/twr/pan2.jpg
33
HAARP -- Feed Sytem
Fromhttp//server5550.itd.nrl.navy.mil/projects/
HAARP/images/ant/tpile.jpg
34
HAARP -- Matching Networks
From http//server5550.itd.nrl.navy.mil/projects/
HAARP/images/ant/amu.jpg
35
Corner Reflector Antenna
From http//www.northcountryradio.com/crfigs.htm
36
Anything Radiates Fan-tenna
Fromhttp//www.qth.com/antenna/fanfull.gif
37
The Bottom Line

• ANYTHING radiates. Sometimes you want it to, and
  sometimes you dont.
• To choose an antenna for your design, prepare a
  LINK BUDGET to determine the necessary gain and
  directivity of your antenna.
• Dont forget MATCHING NETWORKS to prevent
  reflection between your antenna and your circuit.

38
Antenna References on the Web
General http//www.ee.surrey.ac.uk/Personal/D.Jef
feries/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/P
rojects/ANTCAL/index.shtml Ham North Country
Radio http//www.northcountryradio.com/techtips.h
tm Antenna Elmer http//www.qth.com/antenna/anten
na.htm HAARP Observatory http//server5550.itd.n
rl.navy.mil/projects/HAARP/ant3.html Arecibo
Obervatory http//www.naic.edu/aboutao.htm