The document discusses horn antennas, which consist of a flaring metal shape like a horn. Horn antennas were first constructed in 1897 and became widely used in the 1960s as feed horns for satellite dishes and radio telescopes. They work by converting electric power to radio waves and vice versa, providing a gradual impedance transition between a waveguide and free space to efficiently radiate waves. Common types include rectangular, sectoral, pyramidal, and conical horns. Horn antennas are used for applications like radar guns and satellite communications due to properties like high directivity, gain, and bandwidth.

1. T.C
Suleyman Demirel University
College of Engineering
Electronic And Communications Eng. Department
Horn Antenna Representation of
Antenna Theory
By MSc. Students
Khaled Saeed Al Badri
Mohammed Mahdi
A COURSE OFFERED BY: Dr. Evren Ekmekçi

2. What is Horn Antenna:
A horn antenna horn is an antenna that consists of a flaring metal shaped
like a Horn.
By Khalid Saeed And Mohammed Mahdi SDU

3. Horn Antenna
- The first horn antennas constructed by Indian radio researcher in 1897. [3]
- In World War 2 the development stimulated horn research to design feed
horns for radar antennas.[1]
-In 1962 horn antenna has become widely used as a feed horn for
microwave antennas such as satellite dishes and radio telescopes.[3]
50 ft. Holmdel horn antennaThe 64 meter radio telescope
By Khalid Saeed And Mohammed Mahdi SDU

4. How Horn Antenna Work
-Horn Antenna converts the electric power into radio waves and
vise versa. It is usually used with a radio transmitter or radio
receiver.
- It provides a gradual transition structure to match
the impedance of a tube to the impedance of free space, enabling
the waves from the tube to radiate efficiently into
space.
By Khalid Saeed And Mohammed Mahdi SDU

5. Range Of Frequencies:
Horns operates at UHF and Microwave frequencies, above 300 MHz..
By Khalid Saeed And Mohammed Mahdi SDU

6. Waveguide:
Waveguides are rectangular or circular shaped tubes. They are used for
energy and information transfer in electromagnetic systems. Electromagnetic
waves travel along waveguides by means of multiple reflections from the
metallic walls. Generally metallic waveguides have one conductor and
operate at frequencies above 1 GHz.
By Khalid Saeed And Mohammed Mahdi SDU

7. Waveguide:
Metallic waveguides is important components of many technologies with
practical applications such as radar antenna feeds, circuitry, waveguide slot
antenna arrays, horn antennas, microwave filters and other various
other circuit component.
By Khalid Saeed And Mohammed Mahdi SDU

8. Horn Antenna Types:
1. Rectangular feed-horns:
- Sectoral E-plane horns
- Sectoral H-plane horns
- Pyramidal feed-horns
2. Conical feed-horns.
By Khalid Saeed And Mohammed Mahdi SDU

9. Sectoral E-plane horns
In E-plane sectoral horn the opening is flared in the direction of
the E-field.
By Khalid Saeed And Mohammed Mahdi SDU

10. The Radiation Pattern Sectoral E-plane horns
The E-plane pattern is much narrower than the H-plane because
of the flaring and larger dimensions of the horn in that direction
By Khalid Saeed And Mohammed Mahdi SDU

11. H-Plane Sectoral Horn:
In H-plane sectoral horn the opening is flared in the direction of
the H-field, while keeping the other constant.
By Khalid Saeed And Mohammed Mahdi SDU

12. Radiation Pattern of H-Plane Sectoral Horn:
The H-plane pattern is much narrower than the E-plane because
of the flaring and larger dimensions of the horn in that direction
By Khalid Saeed And Mohammed Mahdi SDU

13. Pyramidal Horn:
The most widely used horn is the one which is flared in both directions
and its radiation characteristics are essentially a combination of the E-
and H-plane sectoral horns.
By Khalid Saeed And Mohammed Mahdi SDU

14. Radiation Pattern of Pyramidal Horn:
the pattern of a pyramidal horn is very narrow in both principal
planes and in fact, in all planes.
By Khalid Saeed And Mohammed Mahdi SDU

15. Conical Horn.
Conical feed-horns are fed with a metallic circular waveguide in
mono-mode operation
By Khalid Saeed And Mohammed Mahdi SDU

16. Gain
Horns have very little loss, so the directivity of a horn is roughly equal
to its gain.
The gain G of a pyramidal horn antenna is:
For conical horns, the gain is:
A is the area of the aperture.
d is the aperture diameter of a conical horn
λ is the wavelength,
eA is a dimensionless parameter between 0 and 1 called the aperture efficiency.
By Khalid Saeed And Mohammed Mahdi SDU

17. Why we use Horn Antennas?
- They can operate over wide ranges of frequencies.
- Very wide bandwidth, for example allowing it to operate from
1GHz to 20GHz, 20:1.
- High Directivity.
- High gain.
-Support for wide applications.
By Khalid Saeed And Mohammed Mahdi SDU

18. Applications of Horn Antenna:
- They are used as feeders (called feed horn) for larger antenna
structures such as parabolic antennas, as directive antennas for
such devices as radar guns, automatic doors openers,
microwave radiometer.
- A common element of phase array.
- Satellite and microwave communications.
- Used in the calibration, other high gain antenna.
-Used for making electromagnetic interference measurement.
By Khalid Saeed And Mohammed Mahdi SDU

19. References:
1. Antenna theory analysis and desgin by Balanis.
2. Design and Performance Analysis of 10 GHz Horn Antenna By
ARPN Journal of Science and Technology.
3. http://en.wikipedia.org/wiki/Horn_antenna.
4. Antenna theory by Stutzman.
By Khalid Saeed And Mohammed Mahdi SDU