Electrically, Marconi antenna operates as a Hertz antenna. Physically It is only a one-quarter wavelength (1/4 l) long.

1. HERTZ & MARCONI
ANTENNA
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2. HERTZ & MARCONI
CONTENT
Hertz Antenna
 History
 Construction
 Introduction
 Radiation Pattern
 Gain, Directivity &
Polarization
 Application
Marconi Antenna
 History &
Introduction
 Radiation Pattern
 Design and antenna
modeling
 Application
 Comparison Between Hertz and Marconi
 Reference
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3. HERTZ & MARCONI
HERTZ ANTENNA
HISTORY
 Professor Heinrich Hertz made the first radio
transmission in 1886 in his
laboratory of
Karlsrhule University.
 first antenna, he
invented has the shape shown
in the figure:
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Fig. Hertz Antenna

4. HERTZ & MARCONI
CONSTRUCTION
 dipole can be any length,
but it most commonly is
just under 1/2 wavelength
long
 dipole has an input
impedance that is purely
resistive and lies between
30 and 80 ohm
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Fig. Construction

5. HERTZ & MARCONI
INTRODUCTION
 dipole antenna, with ½ wavelength
 very small, compared to its wavelength that is
about one-hundredths of the wavelength at its
operating frequency
 radiation pattern of hertz antenna is not truly
isotropic
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6. HERTZ & MARCONI
RADIATION PATTERN
 fat doughnut with the dipole piercing its central
hole
 Gain is stronger in the direction of maximum
radiation
 radiation from an isotropic radiator is in the
same direction
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7. HERTZ & MARCONI
RADIATION PATTERN
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Fig. Radiation Pattern

8. HERTZ & MARCONI
GAIN DIRECTIVITY & POLARIZATION:
 Gain of the Hertz Antenna is 2.1dBs
 Directivity a Gain
(i.e. the directivity increases as the gain increases)
 can also be vertically polarized.
 antenna is placed perpendicular, or vertically with
respect to the Earth’s surface
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9. HERTZ & MARCONI
APPLICATIONS:
 normally used for small applications and
was used in set top TV antennas
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10. HERTZ & MARCONI
MARCONI ANTENNA
HISTORY AND INTRODUCTION
 Invented by: Guglielmo Marconi in 1885 in
Bologna
 most common vertical
antenna is known as Marconi
antenna
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Fig. Marconi Antenna

11. HERTZ & MARCONI
RADIATION PATTERN
 radiation resistance is equal to 36.5 Ω
11Fig. Radiation Pattern Of Marconi Antenna

12. HERTZ & MARCONI
DESIGN AND ANTENNA MODELING
 vertical wire with a length of 1/4 of the working
wavelength
 length of the wire in meters is calculated as
L = ( 71,25 / Frequency MHz)
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13. HERTZ & MARCONI
APPLICATION
 used in the radio broadcasting transmitters of
high power
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14. HERTZ & MARCONI
COMPARISON BETWEEN HERZ AND
MARCONI
 Electrically,
Marconi antenna operates as a Hertz
antenna.
 Physically
It is only a one-quarter wavelength (1/4 l)
long.
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15. HERTZ & MARCONI
REFERENCE
 www.rfcec.com_RFCEC_Section-3 - Fundamentals of RF
Communication-Electronics_07 - ANTENNA_Antenna - Description
of Antenna 03 Marconi (Vertical) (By Larry E. Gugle K4RFE)
 https://www.scribd.com/doc/54010193/Hertz-
Discone-Antenna-Report
Visited Date : August 2, 2016
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16. HERTZ & MARCONI
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