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1. Antenna Design Documentation
Transmission Media & Antenna System
ECE123/B12

2. ANTENNA
• These are seen in different applications like
radio broadcasting, broadcast television, cell
phones, satellites and even Bluetooth enabled
devices are devices that uses radio.
• Antennas is a kind of an electronic devices
that are used to transmit and receive radio
signals that are used to send information.
• These converts the radio frequency gotten
into an electromagnetic field.

3. PARABOLIC REFLECTOR
ANTENNA
• consists of a parabolic reflector
illuminated by a small feed
antenna
• typically have a very high gain (30-
40 dB is common) and a low cross
polarization.
• have reasonable bandwidth, with
the fractional bandwidth being at
least 5% on commercially available
models, and it can be very
wideband in the case of huge dishes

4. Driven Element
• In a transmitting antenna, it is driven or excited by
the RF current from the transmitter, and is the
source of the radio waves.
• In a receiving antenna, it collects the incoming
radio waves for reception, and converts them to tiny
oscillating electric currents, which are applied to
the receiver.
• . The parasitic elements act as resonators and
couple electromagnetically with the driven element,
and serve to modify the radiation pattern of the
antenna, directing the radio waves in one direction,
increasing the gain of the antenna.

5. Parasitic Element
• In electrical networks, a parasitic element is a circuit
element that is possessed by an electrical
component but which it is not desirable for it to have for
its intended purpose.
• Parasitic elements are unavoidable.
• All conductors possess resistance and inductance and
the principles of duality ensure that where there is
inductance, there will also be capacitance.

6. Corner Reflector
• It consists of two flat rectangular
reflecting screens joint at an angle,
usually 90deg, with a mounted
dipole driven element in front of it.
Corner reflectors have
moderate gain of 10-
15 dB, high front-to-back ratio of
20-30 dB, and wide bandwidth.
• They radiate linearly
polarized radio waves and can be
mounted for either horizontal or
vertical polarization.

7. Simulation
• For this design project both parabolic and corner
reflector was simulated for comparison with its
gain.
• The antenna designed was an antenna for DTV
GMA that has a frequency of 551 MHz and the
element is AWG 10.
• There are a total of 4 situations simulated first, a
director of 0.1λ and 0.2 λ for both the parabolic and
corner antenna.

8. Figure 6. Parabolic 0.1λ 3D Figure 7. Parabolic 0.1λ 2D

9. Figure 8. Parabolic 0.1λ
(other parameters)

10. Figure 9. Parabolic 0.2λ 3D Figure 10. Parabolic 0.2λ 2D

11. Figure 11. Parabolic 0.2λ
(other parameters)

12. Figure 12. Corner 0.1λ 3D Figure 13. Corner 0.1λ 2D

13. Figure 14. Corner 0.1λ
(other parameters)

14. Figure 15. Corner 0.2 λ 3D Figure 16. Corner 0.2 λ 2D

15. Figure 17. Corner 0.2 λ
(other parameters)

25. Solution
• Theoretical: Cylindrical with
Parabolic Cross Section
• Distance of Reflector to driven dipole:
0.1λ ; 0.2 λ
• Width of Reflector:
105%
=0.2853 m

26. • Length of the Driven Dipole:
• Length of director:
.95%
= 0.256
• Length of Reflector:
= 0.218
• Radius of AWG 10:
= 0.026 mm

27. • Theoretical: Corner Reflector 90 degrees
; = 0.081

28. VARIATIONS
Cylindrical with Parabolic Cross Section
Table 1. Cylindrical with Parabolic Cross Section
Variation Distance from
the driven
element
Maximum Gain
0.02λ 7.15dBi
0.04λ
7.93dBi
0.06λ
7.86dBi
0.08λ
7.43dBi
0.1λ
7.67dBi
0.12λ
8.11dBi
0.14λ
8.49dBi
0.16λ
8.74dBi
0.18λ
8.87dBi
0.2λ
8.87dBi

29. Corner 90 degrees
Table 2. Corner Reflector 90 degrees’ variations
Distance from the
driven element
Maximum Gain
0.02λ 7.47dBi
0.04λ 7.99dBi
0.06λ
7.78dBi
0.08λ
7.42dBi
0.1λ
7.81dBi
0.12λ
8.26dBi
0.14λ
8.59dBi
0.16λ
8.72dBi
0.18λ
8.67dBi
0.2λ
8.46dBi

30. FABRICATED
ANTENNA
• The fabricated prototype was based on the design
of a Cylindrical Reflector that has a parabolic cross
section and with a feed 0.1λ away from the
reflector.
• For the design requirements of 5 elements the
fabricated antenna has 6 because in the actual 5
elements for a cylindrical that has a parabolic
cross section is not possible.

31. Figure 12. Prototype (front) Figure 13. Prototype (top)

32. Figure 14. Prototype (side) Figure 15. Prototype (testing)

33. Conclusion
• The total gain of the chosen antenna in simulation was
7.79 dBi which is slightly higher than the gain of the
simulated Corner Reflector with angle of 90 degrees
which is 7.5 dBi.
• As observed from the simulations the cylindrical with a
distance of 0.2λ has the largest gain compared to the 0.1
λ for cylindrical and both 0.1 and 0.2 λ for the corner
reflector having a total gain of 7.81 dBi but still the
chosen design to be fabricated was the cylindrical with
0.1λ distance due to the Spillover Efficiency

34. References
• [1] “Parabolic Antenna”, radartutorial.eu, 2016.
[Online]. Available:
http://www.radartutorial.eu/06.antennas/Parabolic%20A
ntenna.en.html
• [2] “Parabolic Antenna”, idc-online.com, [Online].
Available:
http://www.idc-online.com/technical_references/pdfs/elec
tronic_engineering/Parabolic_Antenna.pdf