Importance of Microwave Antennas in Communication System

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:

1. Micro strip patch antenna
2. Horn antenna
3. Parabolic antenna
4. Plasma antenna
5. MIMO antenna

All the above types of antennas, their importance and applications are briefly discussed below.

1. 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.

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.

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

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.

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, ideas and comments about this article in the comments section given below.

Photo Credits

• Micro strip patch antenna by amitsingh
• Plasma antenna by twistedphysics
• Horn antenna by radio-electronics
• MIMO antenna by electronicdesign