The W band of the

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 ra ...

part of the

electromagnetic spectrum The electromagnetic spectrum is the range of frequencies (the spectrum) of electromagnetic radiation and their respective wavelengths and photon energies. The electromagnetic spectrum covers electromagnetic waves with frequencies ranging fro ...

ranges from 75 to 110

GHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

, wavelength ≈2.7–4 mm. It sits above the U.S.

IEEE The Institute of Electrical and Electronics Engineers (IEEE) is a 501(c)(3) professional association for electronic engineering and electrical engineering (and associated disciplines) with its corporate office in New York City and its operati ...

-designated V band (40–75 GHz) in frequency, and overlaps the NATO designated M band (60–100 GHz). The W band is used for satellite communications, millimeter-wave

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, Marine radar, ships, spacecraft, guided missiles, motor v ...

research, military radar targeting and tracking applications, and some non-military applications.

Radar

A number of passive millimeter-wave cameras for concealed weapons detection operate at 94 GHz. A frequency around 77 GHz is used for automotive cruise control radar. The atmospheric radio window at 94 GHz is used for imaging millimeter-wave radar applications in astronomy, defense, and security applications.

Heat ray

Less-than-lethal weaponry exists that uses millimeter waves to heat a thin layer of human skin to an intolerable temperature so as to make the targeted person move away. A two-second burst of the 95 GHz focused beam heats the skin to a temperature of 130 °F (54 °C) at a depth of 1/64 of an inch (0.4 mm). The

United States Air Force The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Si ...

and

Marines Marines, or naval infantry, are typically a military force trained to operate in littoral zones in support of naval operations. Historically, tasks undertaken by marines have included helping maintain discipline and order aboard the ship (refl ...

are currently using this type of

Active Denial System The Active Denial System (ADS) is a non-lethal directed-energy weapon developed by the U.S. military, designed for area denial, perimeter security and crowd control. Informally, the weapon is also called the heat ray since it works by heating th ...

Communications

In terms of communications capability, W band offers high data rate throughput when used at high altitudes and in space. (The 71–76 GHz81–86 GHz segment of the W band is allocated by the

International Telecommunication Union The International Telecommunication Union is a specialized agency of the United Nations responsible for many matters related to information and communication technologies. It was established on 17 May 1865 as the International Telegraph Unio ...

to satellite services.) Because of increasing spectrum and orbit congestion at lower frequencies, W-band satellite allocations are of increasing interest to commercial satellite operators, although no commercial project has yet been implemented in these bands.

References

External links

A cloud radar at 94 GHz
{{EMSpectrum Microwave bands

Radar

Heat ray

Communications

References

Further reading

External links