A system used for transferring the data
between persons and equipments is called communication system. The
system usually consists of individual Communication networks,
relay stations, transmission system, terminal equipment,
interconnection cable and inter-operations performing as an integrated
whole.
Antenna plays
a crucial role in this communication system, which is used to transmit
and receive the data. The classification of the antenna is based on the
specifications like frequency, polarization, radiation, etc.
The antenna that is operated at
microwave frequency is knows as microwave antenna. There are different
types of microwave antennas over a wide range of applications including
home- communication based applications.
Classification of microwave antennas:
- Micro strip patch antenna
- Horn antenna
- Parabolic antenna
- Plasma antenna
- MIMO antenna
All the above types of antennas, their importance and applications are briefly discussed below.
1. Micro Strip Patch Antenna
Micro strip patch antenna
These antennas are also known as patch
antennas. A micro strip patch antenna consists of a radiating patch that
is bonded to a dielectric substrate on one side and has a ground plane
on the other side.
The patch is generally composed of
conducting materials like copper or gold. The operational frequency of
these antennas range between 100 MHz and 100 GHz. Due to the advantages
like less weight, low volume and low fabrication cost, these antennas
can be manufactured in large quantities.
The micro strip patch antennas are
well-known for their performance and extent of usage. The usage of micro
strip antennas in the wide range could take over the usage of
conventional antennas in applications.
There are several applications that use
the micro-strip patch antennas, such as global positing satellites,
cellular phones, personal communication system and paging devices.
2. Horn Antenna
The Horn antenna or Microwave Horn is an
antenna consisting of a waveguide whose end walls are flared outside to
form a megaphone like structure, as shown in the below figure. These
horns are widely used as antennas at ultra-high frequencies and
microwave frequencies that are well above 300 MHz.
Horn antenna
These are used to measure the gain of
other antennas as calibrating antennas and directive antennas for
devices like automatic door openers and microwave-radio meters.
The advantages of the horn antenna
include moderate directivity, low-standing wave ratio and broad
bandwidth. The gain of horn antenna ranges upto 25 db.These are
extensively used at microwave frequency when the power gain needed is
moderate.
3. Parabolic antenna
A parabola antenna is an antenna that
uses a parabolic reflector, a curved surface with cross sectional shape
of a parabola to direct the radio waves. The shape of the antenna is in
the form of a dish; therefore, it is popularly known as dish antenna or
parabolic dish. High directivity is the main advantage of the parabolic
antenna.
Parabolic antenna
These antennas find their applications
as high gain antennas for point-to-point communication and also as radio
telescopes. In addition to this, the parabolic antennas are also used
as radar antennas because in radars there is a need for transmitting a
narrow beam of radio waves to local objects like ships, airplanes, etc.
4. Plasma Antenna
Plasma antenna
A plasma antenna is a type of radio
antenna in which the plasma is used as a development element instead of
the metal elements that are used in traditional antenna. It uses ionized
gas as a conducting material because this gas ionizes when transmission
or reception takes place.
The Plasma antenna can be used for both
transmission and reception of the radio signals as they are capable of
operating upto 90GHz frequency range.
The plasma antenna has high frequency
cutoff .It can transmit and receive high and low-frequency signals while
not interacting with the high frequency signals. The applications of
the plasma antenna are high speed digital communications, electronic
intelligence, RFID, 4G and radar systems.
5. MIMO antenna
In
radio, multiple inputs and multiple outputs or MIMO are used, and
therefore, the multiple antennas are used at both the transmitter and
receiver ends to improve communication’s performance. It is one of the
smart antenna technologies.
MIMO antenna
The multiple antennas in MIMO can be
exploited in two ways: one is for the creation of highly effective
antenna directivity, and the other is for transmitting the parallel data
streams to increase the capacity of the system. The applications of the
MIMO antennas are mesh networks and RFID systems.
The above described various micro wave antennas are essential devices in wireless communication systems
and also in satellite, radio and radar communications. We hope that you
are satisfied with the above content. Please write your suggestions,
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