Milešovka_(837_m),_satelity_s_výhledem_do_krajiny

A microwave antenna is a physical transmission device used to broadcast

microwave Microwave is a form of electromagnetic radiation with wavelengths ranging from about one meter to one millimeter corresponding to frequencies between 300 MHz and 300 GHz respectively. Different sources define different frequency ran ...

transmissions between two or more locations. In addition to broadcasting, antennas are also used in

radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, w ...

radio astronomy Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming f ...

and

electronic warfare Electronic warfare (EW) is any action involving the use of the electromagnetic spectrum (EM spectrum) or directed energy to control the spectrum, attack an enemy, or impede enemy assaults. The purpose of electronic warfare is to deny the opponen ...

Microwave frequency bands

Uses

* One-way (e.g.

television broadcasting A television network or television broadcaster is a telecommunications network for distribution of television program content, where a central operation provides programming to many television stations or pay television providers. Until the mid-1 ...

) and two-way telecommunication using

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...

s * Terrestrial microwave relay links in telecommunications networks including backbone or backhaul carriers in

cellular network A cellular network or mobile network is a communication network where the link to and from end nodes is wireless. The network is distributed over land areas called "cells", each served by at least one fixed-location transceiver (typically thre ...

s linking

BTS BTS (), also known as the Bangtan Boys, is a South Korean boy band formed in 2010 and debuting in 2013 under Big Hit Entertainment. The septet—consisting of members Jin, Suga, J-Hope, RM, Jimin, V, and Jungkook—co-writes and co-produ ...

BSC A Bachelor of Science (BS, BSc, SB, or ScB; from the Latin ') is a bachelor's degree awarded for programs that generally last three to five years. The first university to admit a student to the degree of Bachelor of Science was the University ...

and BSC- MSC. *

Radar Radar is a detection system that uses radio waves to determine the distance (''ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, w ...

Radio astronomy Radio astronomy is a subfield of astronomy that studies celestial objects at radio frequencies. The first detection of radio waves from an astronomical object was in 1933, when Karl Jansky at Bell Telephone Laboratories reported radiation coming f ...

Communications intelligence Signals intelligence (SIGINT) is list of intelligence gathering disciplines, intelligence-gathering by interception of ''Signal, signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from ele ...

Electronic warfare Electronic warfare (EW) is any action involving the use of the electromagnetic spectrum (EM spectrum) or directed energy to control the spectrum, attack an enemy, or impede enemy assaults. The purpose of electronic warfare is to deny the opponen ...

Antenna types

Reflector antennas

parabolic antenna A parabolic antenna is an antenna that uses a parabolic reflector, a curved surface with the cross-sectional shape of a parabola, to direct the radio waves. The most common form is shaped like a dish and is popularly called a dish antenna or pa ...

is an

antenna Antenna ( antennas or antennae) may refer to: Science and engineering * Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves * Antennae Galaxies, the name of two collid ...

that uses a

parabolic reflector A parabolic (or paraboloid or paraboloidal) reflector (or dish or mirror) is a reflective surface used to collect or project energy such as light, sound, or radio waves. Its shape is part of a circular paraboloid, that is, the surface generated ...

, a curved surface with the cross-sectional shape of a

parabola In mathematics, a parabola is a plane curve which is mirror-symmetrical and is approximately U-shaped. It fits several superficially different mathematical descriptions, which can all be proved to define exactly the same curves. One descript ...

, to direct the radio waves. These devices range anywhere from 6" to more than 12' diameter depending on application and use.

Horn antennas

horn antenna A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct radio waves in a beam. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz. They are us ...

or microwave horn is an antenna that consists of a flaring metal

waveguide A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting the transmission of energy to one direction. Without the physical constraint of a waveguide, wave intensities de ...

shaped like a

horn Horn most often refers to: *Horn (acoustic), a conical or bell shaped aperture used to guide sound ** Horn (instrument), collective name for tube-shaped wind musical instruments *Horn (anatomy), a pointed, bony projection on the head of various ...

to direct radio waves in a beam. Horns are widely used as antennas at UHF and

frequencies, above 300 MHz.

Lens antennas

lens antenna A lens antenna is a microwave antenna that uses a shaped piece of microwave-transparent material to bend and focus the radio waves by refraction, as an optical lens does for light. Typically it consists of a small feed antenna such as a patch a ...

uses a lens to direct or collect microwave radiation.

Array antennas

array antenna An antenna array (or array antenna) is a set of multiple connected antennas which work together as a single antenna, to transmit or receive radio waves. The individual antennas (called ''elements'') are usually connected to a single receiver ...

is a high gain antenna consisting of an array of smaller antenna elements.

Leaky wave antenna

A leaky wave antenna uses a leaking transmission line to obtain radiation.

References

{{Reflist Telecommunications equipment Radio frequency antenna types