How Does an Antenna Work?

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How Does an Antenna Work?
Antenna is used widely in the telecommunication
field, military operations, and other
applications. It gets an electromagnetic wave and
converts it into electric signals. Some antennas
receive electric signals and radiate them as
electromagnetic waves. A simple radio antenna is
a long straight rod. Many indoor TV antennas
take the form of a dipole that is divided into 2
pieces and folded horizontally. Numerous outdoor
TV antennas have more than one dipole with a
central supporting rod. The different types of
antenna designs include parabolic satellite
dishes and circular loops of wire. Generally,
the waves emitting at the antenna from a
transmitter are the same in any shape of the
antenna. Different patterns of dipoles help to
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• concentrate the signals for easy detection. This
  effect can be increased by adding many
  unconnected dummy dipoles called reflectors and
  directors. These dipoles bounce the signals over
  the actual receiving dipoles. This is similar to
  boosting the signals and picking weaker signals
  better than a simple antenna. We will further
  discuss the working of different kinds of
  antennas and the science behind their working. We
  will also discuss the various types of antennas
  and their different properties.
• Important Features of Antennas
• An Antenna contains many important features such
  as
• Gain
• The gain of an antenna is a technical measurement
  and the amount at which the signals are boosted.
  Television will pick up a poor signal without an
  antenna plugged in. Metal cases and other
  components pick up some kinds of signals by
  default. You need to add a proper directional
  antenna to gain better signals.
• The gain of an antenna is often measured in
  decibels (DB). You will receive a better
  reception with a bigger gain. Outdoor antennas
  work more effectively than outdoor antennas.
• Directionality
• Dipole is very directional and picks up incoming
  radio waves traveling at right angles to them.
  The telescopic antenna on an FM radio is less
  directional when the signals are strong. If the
  telescopic antenna is pointed straight upward,
  it will capture good signals from any direction.
• AM antenna in the radio is very directional.
  While using AM, you will need to swivel the
  radio until it picks up strong signals. Highly
  directional

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• antennas give ample benefits such as reduction in
  interference from unwanted sources or signals.
• Bandwidth
• The bandwidth of an antenna refers to the
  frequency range on which it works perfectly.
  Broader bandwidth gives a greater range of radio
  waves. Broad bandwidth will be more helpful in
  the case of television but not in other cases
  like satellite communications, telephones, or
  cell phones.
• Different Kinds of Antennas
• An antenna is a tool used for receiving and
  transmitting signals. It comes in various
  shapes, sizes, and features according to the
  needs of the customers. We will now discuss the
  different types of antennas and how they work.
• 1. Dipole Antenna
• Dipole antennas normally contain 2 similar
  conductive elements like rods or metal wires.
  This kind of antenna includes odd and even modes.
  It contains a center-fed driven element to
  transmit and receive radio frequency energy. It
  is the simplest type of antenna containing a
  straight electric conductor made of metals like
  copper thereby making 2 poles.
• The metal wire length is half of the highest
  wavelength in free space at the frequency
  operation. The conductive materials in the center
  of an antenna are divided through an insulator
  known as an antenna section. The RF voltage
  source is normally given to the middle of the
  Dipole Antenna. Voltage and current are then
  supplied via the 2 conductive elements to
  produce radio or electromagnetic signals. These
  signals are later radiated outside the dipole
  antenna. In the center of a dipole

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• antenna, the voltage is minimum and current is
  maximum whereas the current is minimum and
  voltage is maximum at the two ends of an
  antenna.
• Grid Parabolic Antenna
• Grid antenna is a kind of parabolic antenna. It
  normally contains a reflector made from a grill
  of parallel wires or bars targeted in one
  direction that acts as a polarizing filter and a
  reflector. These antennas normally reflect
  linearly polarized radio waves with an electric
  field parallel to the grill elements. The
  spacing of the grid elements is frequently
  dependent and inversely proportional to the
  frequency.
• Grid parabolic antenna has the highest weight
  ratio and strength. It is a very efficient
  antenna in which gain figures approach the
  theoretical maximum for the curved surface area.
  This antenna contains a full Parabolic reflector
  for a smooth digital communication system.
• Yagi Antenna
• The Yagi antenna was discovered by 2 Japanese
  scientists Shintaro Uda and Hidetsugu Yagi. It
  is a kind of directional antenna and is generally
  used in point-to-point communication. Yagi
  antenna radiates signals in one fixed direction.
  It includes a long transmission line with a
  single driven element containing two rods
  connected on any one side of the transmission
  lines.
• This antenna contains a single reflector on one
  side of the transmission line and several
  parasite elements that act as directors. In Yagi
  antennas, the reflector is kept behind the
  driven element and is longer than the driven
  element. On the other hand, the director is kept
  on the front of

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the driven element and is shorter than the driven
element. Normally, Yagi antennas have one
reflector and multiple directors. 4. Satellite
dish antenna Dish Antenna are popular these days.
They contain 2 major components namely parabolic
shaped reflector and a low noise block down
convertor. Parabolic dish gets electromagnetic
signals from the satellite and focuses them on
LNBF. Final words This is all about a High Gain
Antenna with its working pattern, design and
features. The working of every kind of antenna is
almost similar with slight changes. These
antennas are used in multiple applications from
satellite communication to telephone lines. Many
antenna manufacturers and dealers sell the
different kinds of antennas online at affordable
rates.