The atmospheric attenuation of microwaves in dry air with a precipitable water vapor level of 0.001 mm. The downward spikes in the graph corresponds to frequencies at which microwaves are absorbed more strongly, such as by oxygen molecules.
A 1 Gbit/s point-to-point millimeter-wave link installed in the UAE
A parabolic satellite antenna for Erdfunkstelle Raisting, based in Raisting, Bavaria, Germany
A point-to-point wireless unit with a built-in antenna at Huntington Beach, California
C-band horn-reflector antennas on the roof of a telephone switching center in Seattle, Washington, part of the U.S. AT&T Long Lines microwave relay network
Dozens of microwave dishes on the Heinrich-Hertz-Turm in Hamburg, Germany
Communications tower on Frazier Mountain, Southern California with microwave relay dishes
Danish military radio relay node
Production truck used for remote broadcasts by television news has a microwave dish on a retractible telescoping mast to transmit live video back to the studio.
Antennas of 1931 experimental 1.7 GHz microwave relay link across the English Channel. The receiving antenna (background, right) was located behind the transmitting antenna to avoid interference.
US Army Signal Corps portable microwave relay station, 1945. Microwave relay systems were first developed in World War II for secure military communication.
Richtfunkstelle Berlin-Frohnau
Microwave spying

Other examples of point-to-point communications links are leased lines and microwave radio relay.

- Point-to-point (telecommunications)

Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna.

- Microwave transmission
The atmospheric attenuation of microwaves in dry air with a precipitable water vapor level of 0.001 mm. The downward spikes in the graph corresponds to frequencies at which microwaves are absorbed more strongly, such as by oxygen molecules.

3 related topics with Alpha

Overall

Earth station at the satellite communication facility in Raisting, Bavaria, Germany

Telecommunications

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Transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems.

Transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems.

Earth station at the satellite communication facility in Raisting, Bavaria, Germany
Visualization from the Opte Project of the various routes through a portion of the Internet
A replica of one of Chappe's semaphore towers
Optical fiber provides cheaper bandwidth for long-distance communication.
Digital television standards and their adoption worldwide
here
The OSI reference model

20th- and 21st-century technologies for long-distance communication usually involve electrical and electromagnetic technologies, such as telegraph, telephone, television and teleprinter, networks, radio, microwave transmission, optical fiber, and communications satellites.

Telecommunication over fixed lines is called point-to-point communication because it is between one transmitter and one receiver.

Erdfunkstelle, a large parabolic satellite communications antenna in Raisting, Bavaria, Germany, the biggest facility for satellite communication in the world. It has a Cassegrain type feed.

Parabolic antenna

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Antenna that uses a parabolic reflector, a curved surface with the cross-sectional shape of a parabola, to direct the radio waves to the receiver in its focal point.

Antenna that uses a parabolic reflector, a curved surface with the cross-sectional shape of a parabola, to direct the radio waves to the receiver in its focal point.

Erdfunkstelle, a large parabolic satellite communications antenna in Raisting, Bavaria, Germany, the biggest facility for satellite communication in the world. It has a Cassegrain type feed.
Parabolic antennas are based on the geometrical property of the paraboloid that the paths FP1Q1, FP2Q2, FP3Q3 are all the same length. So a spherical wavefront emitted by a feed antenna at the dish's focus F will be reflected into an outgoing plane wave L travelling parallel to the dish's axis VF.
Wire grid-type parabolic antenna used for MMDS data link at a frequency of 2.5-2.7 GHz. It is fed by a vertical dipole under the small aluminum reflector on the boom. It radiates vertically polarized microwaves.
Main types of parabolic antenna feeds.
Array of multiple feed horns on a German airport surveillance radar antenna to control the elevation angle of the beam
Effect of the feed antenna radiation pattern (small pumpkin-shaped surface) on spillover. Left: With a low gain feed antenna, significant parts of its radiation fall outside the dish. Right: With a higher gain feed, almost all its radiation is emitted within the angle of the dish.
Radiation pattern of a German parabolic antenna. The main lobe (top) is only a few degrees wide. The sidelobes are all at least 20 dB below (1/100 the power density of) the main lobe, and most are 30 dB below. (If this pattern was drawn with linear power levels instead of logarithmic dB levels, all lobes other than the main lobe would be much too small to see.)
The angle theta is normal to the aperture.

Parabolic antennas are used as high-gain antennas for point-to-point communications, in applications such as microwave relay links that carry telephone and television signals between nearby cities, wireless WAN/LAN links for data communications, satellite communications and spacecraft communication antennas.

Wireless icon

Wireless network

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Computer network that uses wireless data connections between network nodes.

Computer network that uses wireless data connections between network nodes.

Wireless icon
Computers are very often connected to networks using wireless links, e.g. WLANs
Wireless LANs are often used for connecting to local resources and to the Internet
Example of frequency reuse factor or pattern 1/4
In a hidden node problem Station A can communicate with Station B. Station C can also communicate with Station B. However, Stations A and C cannot communicate with each other, but their signals can interfere at B.
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Understanding of SISO, SIMO, MISO and MIMO. Using multiple antennas and transmitting in different frequency channels can reduce fading, and can greatly increase the system capacity.

Fixed wireless technology implements point-to-point links between computers or networks at two distant locations, often using dedicated microwave or modulated laser light beams over line of sight paths.

The wireless connections between access points are usually point to point microwave links using parabolic dishes on the 2.4 GHz and 5.8 GHz band, rather than omnidirectional antennas used with smaller networks.