Dipole Antenna: Design, Working, and Types

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Dipole Antenna Design, Working, and Types
The antenna comes in various shapes, materials,
and elements. A Dipole antenna is one of the
most popular kinds of antennas used in different
devices and tools. It is also called a
doublet. In this blog, we will discuss a dipole
antenna, its design, types, benefits and
disadvantages, and many other things related to a
dipole antenna. What is Dipole Antenna? A
doublet dipole or a Military coaxial dipole
antenna is a kind of Radio Frequency antenna
including 2 conductive elements like wire or
rods. It generates a radiation pattern similar
to an elementary electric dipole.
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Dipole antennas are widely used for communication
and other purposes. It is one of the simplest
types of antennas used for transmitting and
receiving antennas. Dipole Antenna Design The
name dipole is 2 poles and this antenna includes
2 same conductive elements like metal wires or
rods. The length of a metal wire in this dipole
antenna is about half of the maximum wavelength
in free space. Feeders at the radiating
and center sections of a dipole antenna are on
one side. The conductive element in the log
periodic antenna is divided in the center into 2
sections via an insulator. This portion is called
an antenna section. This section is connected to
a feeder or coaxial cable in the center of an
antenna. Wavelength is the distance between the
highest or lowest points. In addition, the
radiating element length can be calculated by
several factors like feed impedance and center
operating frequency. The length of a dipole is a
vital parameter. Dipole Antenna Transmitter A
dipole antenna produces radio waves at the
transmitter section. A high voltage is provided
to the antenna at the preferred frequency.
Voltage in the antenna elements and current flow
will produce magnetic and electric waves. A
transmitter is an important element created with
a conductor. This conductor includes electric
current when the intensity of the current changes
with time and converts into RF radiation that
travels in space. Dipole antenna Receiver In the
receiver portion of the antenna, the
electromagnetic waves flowing will produce a
little voltage. This will further make the
antenna a source of signal for the input of the
receiver. Antennas receiver does the reverse
operation of the transmitter. It receives RF
radiation and converts them into electric
currents with the help of an electric circuit
that is attached to the antenna.
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The working system of a Dipole antenna To use a
dipole antenna, you need to apply an RF voltage
source to the center of 2 sections. This voltage
source will produce electromagnetic and radio
wave signals to be radiated outside a dipole
antenna. The voltage is minimum and the electric
current is maximum in the center of the antenna.
On the contrary, the voltage is maximum and the
current is minimum at the ends of the
antenna. In short, the dipole antenna converts
the signals from RF electromagnetic and emits
them at the transmitting end and converts RF
electromagnetic signals into electrical signals
at the end of the receiver. Types of Dipole
Antenna Now, we will discuss the different kinds
of dipole antennas to understand this concept
better. Read below to know the different kinds of
a dipole antenna in the below section Folded
Dipole Antenna The folded dipole antenna is one
of the most popular types. It has 2
dipole antennas that are connected separately to
make a thin wire loop. This kind of antenna is
folded backwards and contains 2 half-wave dipoles
where one is constant and the other is divided
at the center part. These dipole antennas are
folded together in parallel at both ends of an
antenna. Short Dipole Antenna As the name says,
this short dipole antenna has a small length in
comparison to half a wavelength. It is a kind of
simple wire antenna in which there are two ends.
One end is open circulated while the other end is
fed with an AC source. Usually, the frequency
range of a short dipole antenna starts from 3 KHz
and ends at 30MHz. This kind of antenna is used
in various low-frequency-based receivers. In a
short dipole antenna, the antennas length is
shorter than the wavelength. The voltage source
is connected at one end, and the lines are
connected to the other end.
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• Half-wave Dipole Antenna
• The half-wave dipole antenna is a popular kind of
  antenna wherein the total
• length is equal to the half-wavelength at the
  frequency of operation. This antenna is also
  called a doublet or half-wavelength dipole or
  Hertz antenna.
• There are 2-quarter wavelength conductors with
  the feed point at the center. This symmetrical
  antenna has 2 ends connected from equal potential
  to the center point.
• The frequency range of a half-wave dipole antenna
  starts from 3 KHz and ends at
• 300 GHz. Many radio receivers use half-wave
  dipole antennas for clear transmissions.
• FM Dipole Antenna
• FM dipole antenna is a cost-effective antenna
  that is very easy to make. Because
• of affordable cost, these antennas are used
  widely in roof space in internal FM antenna. The
  most common task of FM dipole antennas is
  offering better
• reception of VHF FM broadcasting. They are used
  in FM broadcasting and their
• frequency range starts from 88 MHz and goes up to
  108 MHZ.
• Fan Dipole Antenna
• The fan dipole antenna is also known as a
  parallel or fanned dipole antenna. It is
• a kind of multi-band antenna and is easy to
  design. Fan dipole antenna contains many small
  dipole antennas with a similar coaxial feed line.
  When the signal is transmitted, the resonating
  element is observed through the radio.
• You can arrange the mechanical design of a fan
  dipole antenna in an inverted V shape
  horizontally. Some arrangements can be made with
  the help of adjacent spread wires in various
  directions. In this antenna, some elements
  interfere with each other because of tight
  arrangement.

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• Even though the antenna has gaps,
  these gaps do not affect its performance
  of the antenna.
• To get the smooth working of the antenna, you
  must use a dipole antenna at the resonant
  frequency.
• It is easy to design and install a dipole antenna
  in various configurations such as drooping and
  inverted V.
• This antenna will receive the signal from all
  directions.
• The antenna gives a radiation pattern of a donut
  shape.
• One can reduce a dipole antenna with the help of
  a loading coil.
• Disadvantages of Dipole Antenna
• A dipole antenna has some drawbacks such as
• Low frequencies might not work in this antenna
  because of a long wavelength.
• The antenna will not perform well if the
  efficiency goes below 27 MHz frequencies when
  the length of the antenna reduces.
• Folded type antenna is a complicated kind of
  antenna. You will need professional guidance to
  use a folded-type antenna.
• Outdoor antennas are very bulky. It is difficult
  to install these bulky antennas from one place
  to another.
• Transporting outdoor antennas is difficult
  because of their heavy weight.
• A dipole antenna is not efficient as a typical
  antenna.
• An indoor dipole antenna is very small in the
  size.
• Where is a dipole antenna used?
• A dipole antenna is used for different
  applications such as

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• UHF and VHF antennas are used in different areas
  such as public communication, coastal areas and
  land mobile communication.
• Final words
• This is all about a dipole antenna, its designs,
  working, benefits, and disadvantages. A dipole
  antenna is a very popular type of antenna that
  can be used for TV broadcasting and radio
  transmission. A Dipole antenna is an
• affordable antenna used in various areas for
  gaining solid signals.