20 m hz radio telescope with in phased dipole antenna
1. Using Radio Antennae To Study
Solar Activity
Bhupendra Subedi
Mentor: Vayujeet Gokhale
2. How old is the concept?
âąâŻ Karl Jansky first discovered radio
waves in 1931.
âąâŻ In his 1932 report mentioned that
extraterrestrial sources cause radio
interference
âąâŻ Called the father of radio astronomy
http://www.nrao.edu/whatisra/images/jansky4.jpg
âąâŻ Grote Reber, an American engineer,
in late 1930âs built the first-bowl
shaped radio telescope.
âąâŻ After years of failure, his radio
telescope collected and measured
radio waves given off by objects in
space.
http://http://www.nrao.edu/whatisra/images/grote1.gif
3. Seeing with Radio Telescope
âąâŻ Normally we see âąâŻ Radio Telescope help
when: electromagnetic us see when:
radiation interacts with electromagnetic
cells in our eyes radiation interacts with
our detectors
4. Radio Spectrum and Projects
http://www.radio-astronomy.org/pdf/sara-beginner-
booklet.pdf
5. SID Radio (12-35 KHz)
measures the amplitude fluctuation of radio signals from Radio
transmitters after they have reflected from the ionosphere
6. SID Monitor
http://www.qsl.net/dl4yhf/speclab1.jpg
Power dB
Perceival Andrews, How TO Build Your Own Radio Telescope
8. Fast Facts about IBT
âąâŻ This is a 12,000 MHz radio telescope that can
detect frequencies in the range of 12,200 to
12,700 MHz.
âąâŻ It can detect the sun.
âąâŻ It can detect blackbody radiation such as trees,
buildings, people, when viewed against blank sky.
âąâŻ It is an outdoor instrument.
9. 20 MHz Radio Jove Telescope With In-Phased Dipole
Antenna
âąâŻ The Radio Jove Program
is a simple astronomy
project that can monitor
http://www.enterprisemission.com/
Solar and Jupiter Bursts.
images/jupiter.jpg
âąv=f*λ
âą For 20.1 MHz,
λ = v / fv/f"3*" 10 ^8 " m/s" )/(20.1
â 10 ^6 = 14.925 m
So, length of the dipole
antenna = 14.925/2 = 7.4625
m.
http://thewatchers.adorraeli.com/wp-content/uploads/2011/11/
hxrt_flter_fd_20111129_180351.png
10. The Dipole Antenna
3.76m
E:DirDocumentRefJupiter.pdf Page 79
âąâŻ The more dipoles there are in the
array, the wider the section of the sky
is that signals can be gathered from.
NASA Radio Jove Project
âąâŻThe combined length of the dipole is half the wavelength of the wave a radio
astronomer is trying to observe
So, length of the dipole antenna = λ /2 = 14.925/2 = 7.4625 m.
And each limb of the dipole = 7.4625/2 = 3.76 m
11.
12. An example of a Jove graph
Antenna Temperature
Universal Time
Antenna Temperature: represents the brightness of the radiation source
& is proportional to power per unit area emitted by the source
13. some sample graphs of solar,
galactic activities
Antenna Temp Deg. K * 1000
Universal Time
14. July 7, 2012 Truman State
X class solar flare,
Type 2
15. July 7,2012 Truman State
Type 3 flare
followed by
type 5 flare
S.M White Solar Radio Burst
and Space Weather
By S.M White, Solar Radio Burst
17. Further Research
1. Write a computer code for Itty Bitty
Telescope, there does not seem to be one
existing
2. Monitor Jupiter Bursts
3. Correct the Sudden Ionospheric Disturbance
Amplifier and make it functional to study effects
of SID on radio signals from Radio transmitters.
4. Study other areas of Radio Frequency
Spectrum
18. References
1.⯠Andrews,Percival.:2011 How to Build Your Own Radio Telescope
2.⯠"What is it? What can it do?." National Radio Astronomy Observatory
nPag. Web. 24 Aug 2012.http://www.aoc.nrao.edu/epo/teachers/ittybitty/
3.⯠Theiman, Dr. James. "The Radio Jove Project." National Aeronautics and
Space Administration n. pag. Radio Jove. Wev. 24 Aug 2012.
http://radiojove.gsfc.nasa.gov/
4.⯠White, Stephen M. "Solar Radio Bursts and Space Weatherâ
5.⯠Verschuur, Gerrit L. The Invisible Universe Revealed. 2. New York:
Springer-Verlag New York Inc., 1987. Print.
6.⯠Burke, Bernard, and Francis Graham-Smith. An Introduction to Radio
Astronomy. 2. Cambridge: Cambridge University Press, 1997. Print.
7.⯠"Space Weather Monitors Stanford Solar Center." The SID Monitor.
Stanford SOLAR Center, n.d. Web. 24 Aug 2012. <http://solar-
center.stanford.edu/SID/sidmonitor/>.
Thank You