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43-498: There is no standard definition of Ka-band. IEEE Standard letter designations for Radar Bands define the nominal frequency range for Ka band in the range 27–40  gigahertz (GHz) in Tables 1 and 2 of IEEE Standard 521 i.e. wavelengths from slightly over one centimeter down to 7.5 millimeters. The ITU however approves Ka-band satellite networks in the 17.3-31 GHz frequency range, with most Ka-band satellite networks having uplinks in

86-565: A certain knowledge area, which provide specialized publications, conferences, business networking and other services. In September 2008, the IEEE History Committee founded the IEEE Global History Network , which now redirects to Engineering and Technology History Wiki . The IEEE Foundation is a charitable foundation established in 1973 to support and promote technology education, innovation, and excellence. It

129-475: A closed room, then deleted immediately upon search completion. Privacy advocates are concerned. "We're getting closer and closer to a required strip-search to board an airplane," said Barry Steinhardt of the American Civil Liberties Union. To address this issue, upgrades have eliminated the need for an officer in a separate viewing area. The new software generates a generic image of a human. There

172-429: A few kilometers. Thus, they are useful for densely packed communications networks such as personal area networks that improve spectrum utilization through frequency reuse . Millimeter waves show "optical" propagation characteristics and can be reflected and focused by small metal surfaces and dielectric lenses around 5 to 30 cm (2 inches to 1 foot) diameter. Because their wavelengths are often much smaller than

215-757: A small beam width , further increasing frequency reuse potential. Millimeter waves are used for military fire-control radar , airport security scanners , short range wireless networks , and scientific research. In a major new application of millimeter waves, certain frequency ranges near the bottom of the band are being used in the newest generation of cell phone networks, 5G networks. The design of millimeter-wave circuit and subsystems (such as antennas, power amplifiers, mixers and oscillators) also presents severe challenges to engineers due to semiconductor and process limitations, model limitations and poor Q factors of passive devices. Millimeter waves propagate solely by line-of-sight paths. They are not refracted by

258-424: A small 100 MHz range has been reserved for space-borne radios, limiting this reserved range to a transmission rate of under a few gigabits per second. The band is essentially undeveloped and available for use in a broad range of new products and services, including high-speed, point-to-point wireless local area networks and broadband Internet access . WirelessHD is another recent technology that operates near

301-478: Is also used for remote sensing of clouds by radar, by both ground-based or satellite systems such as INCUS . In satellite communications, the K a band allows higher bandwidth communication. It was first used in the experimental ACTS Gigabit Satellite Network , and is currently used for high-throughput satellite Internet access in geostationary orbit (GEO) by the Inmarsat I-5 system, Kacific K-1 satellite,

344-649: Is an American 501(c)(3) professional association for electrical engineering , electronics engineering , and other related disciplines. The IEEE has a corporate office in New York City and an operations center in Piscataway, New Jersey . The IEEE was formed in 1963 as an amalgamation of the American Institute of Electrical Engineers and the Institute of Radio Engineers . The IEEE traces its founding to 1884 and

387-437: Is called millimeter waves , sometimes abbreviated MMW or mmWave . Millimeter-length electromagnetic waves were first investigated by Jagadish Chandra Bose , who generated waves of frequency up to 60   GHz during experiments in 1894–1896. Compared to lower bands, radio waves in this band have high atmospheric attenuation : they are absorbed by the gases in the atmosphere. Absorption increases with frequency until at

430-851: Is commonly used by cosmic microwave background experiments . 5th generation mobile networks will also partially overlap with the K a band (28, 38, and 60 GHz). ELF 3 Hz/100 Mm 30 Hz/10 Mm SLF 30 Hz/10 Mm 300 Hz/1 Mm ULF 300 Hz/1 Mm 3 kHz/100 km VLF 3 kHz/100 km 30 kHz/10 km LF 30 kHz/10 km 300 kHz/1 km MF 300 kHz/1 km 3 MHz/100 m HF 3 MHz/100 m 30 MHz/10 m VHF 30 MHz/10 m 300 MHz/1 m UHF 300 MHz/1 m 3 GHz/100 mm SHF 3 GHz/100 mm 30 GHz/10 mm EHF 30 GHz/10 mm 300 GHz/1 mm THF 300 GHz/1 mm 3 THz/0.1 mm IEEE The Institute of Electrical and Electronics Engineers ( IEEE )

473-677: Is incorporated separately from the IEEE, although it has a close relationship to it. Members of the Board of Directors of the foundation are required to be active members of IEEE, and one third of them must be current or former members of the IEEE Board of Directors. Initially, the role of the IEEE Foundation was to accept and administer donations for the IEEE Awards program, but donations increased beyond what

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516-412: Is no anatomical differentiation between male and female on the image, and if an object is detected, the software only presents a yellow box in the area. If the device does not detect anything of interest, no image is presented. Passengers can decline scanning and be screened via a metal detector and patted down. According to Farran Technologies, a manufacturer of one model of the millimeter wave scanner,

559-454: Is particularly associated with the range of 40–70 GHz . This type of treatment may be called millimeter wave therapy or extremely high frequency therapy . This treatment is associated with eastern European nations (e.g., former USSR nations). The Russian Journal Millimeter waves in biology and medicine studies the scientific basis and clinical applications of millimeter wave therapy. Traffic police use speed-detecting radar guns in

602-511: Is the International Telecommunication Union designation for the band of radio frequencies in the electromagnetic spectrum from 30 to 300 gigahertz (GHz). It lies between the super high frequency band and the far infrared band, the lower part of which is the terahertz band . Radio waves in this band have wavelengths from ten to one millimeter, so it is also called the millimeter band and radiation in this band

645-542: Is used commonly in flat terrain. The 71–76, 81–86 and 92–95 GHz bands are also used for point-to-point high-bandwidth communication links. These higher frequencies do not suffer from oxygen absorption, but require a transmitting license in the US from the Federal Communications Commission (FCC). There are plans for 10 Gbit/s links using these frequencies as well. In the case of the 92–95 GHz band,

688-399: Is used in communications satellite uplinks in either the 27.5 GHz or 31 GHz bands, and in high-resolution, close-range targeting radars aboard military airplanes. Some frequencies in this radio band are used for vehicle speed detection by law enforcement. The Kepler Mission used this frequency range to downlink the scientific data collected by the space telescope.This frequency

731-504: The 2022 Russian invasion of Ukraine and requesting the IEEE Spectrum to acknowledge "that they have unwittingly published a piece furthering misinformation and Russian propaganda." A few days later a note from the editors was added on April 6 with an apology "for not providing adequate context at the time of publication", though the editors did not revise the original article. Extremely high frequency Extremely high frequency

774-603: The Advanced Microwave Sounding Unit (AMSU) on one NASA satellite (Aqua) and four NOAA (15–18) satellites and the special sensor microwave/imager (SSMI/S) on Department of Defense satellite F-16 make use of this frequency range. In the United States, the band 36.0–40.0 GHz is used for licensed high-speed microwave data links, and the 60 GHz band can be used for unlicensed short range (1.7 km) data links with data throughputs up to 2.5 Gbit /s. It

817-587: The American Institute of Electrical Engineers . In 1912, the rival Institute of Radio Engineers was formed. Although the AIEE was initially larger, the IRE attracted more students and was larger by the mid-1950s. The AIEE and IRE merged in 1963. The IEEE is headquartered in New York City , but most business is done at the IEEE Operations Center in Piscataway, New Jersey , opened in 1975. The Australian Section of

860-728: The SES-17 satellite in GEO (launched in October 2021; in position and fully operational in June 2022) and the O3b mPOWER constellation in MEO (first two satellites launched December 2022, nine more 2023-2024, and starting service in Q3 2023). The K a band is more susceptible to rain attenuation than is the K u band , which in turn is more susceptible than the C band . The frequency

903-568: The ionosphere nor do they travel along the Earth as ground waves as lower frequency radio waves do. At typical power densities they are blocked by building walls and suffer significant attenuation passing through foliage. Absorption by atmospheric gases is a significant factor throughout the band and increases with frequency. However, this absorption is maximum at a few specific absorption lines , mainly those of oxygen at 60 GHz and water vapor at 24 GHz and 184 GHz. At frequencies in

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946-484: The upper atmosphere by measuring radiation emitted from oxygen molecules that is a function of temperature and pressure. The International Telecommunication Union non-exclusive passive frequency allocation at 57–59.3 GHz is used for atmospheric monitoring in meteorological and climate sensing applications and is important for these purposes due to the properties of oxygen absorption and emission in Earth's atmosphere. Currently operational U.S. satellite sensors such as

989-595: The "severe legal implications" of U.S. government sanctions against Huawei. As members of its standard-setting body, Huawei employees could continue to exercise their voting rights, attend standards development meetings, submit proposals and comment in public discussions on new standards. The ban sparked outrage among Chinese scientists on social media. Some professors in China decided to cancel their memberships. On June 3, 2019, IEEE lifted restrictions on Huawei's editorial and peer review activities after receiving clearance from

1032-418: The "windows" between these absorption peaks, millimeter waves have much less atmospheric attenuation and greater range, so many applications use these frequencies. Millimeter wavelengths are the same order of size as raindrops , so precipitation causes additional attenuation due to scattering ( rain fade ) as well as absorption. The high free space loss and atmospheric absorption limit useful propagation to

1075-415: The 27.5-31 GHz and downlinks in the 17.7-21.2 GHz range. The band is called K a , short for "K-above" because it is the upper part of the original (now obsolete) NATO K band , which was split into three bands because of the presence of the atmospheric water vapor resonance peak at 22.24 GHz (1.35 cm), which made the center unusable for long range transmission. The 30/20 GHz band

1118-450: The 60 GHz range. Highly directional, "pencil-beam" signal characteristics permit different systems to operate close to one another without causing interference. Potential applications include radar systems with very high resolution. The Wi-Fi standards IEEE 802.11ad and IEEE 802.11ay operate in the 60 GHz ( V band ) spectrum to achieve data transfer rates as high as 7 Gbit/s and at least 20 Gbit/s , respectively. Uses of

1161-544: The IEEE existed between 1972 and 1985, after which it split into state- and territory-based sections. As of 2023 , IEEE has over 460,000 members in 190 countries, with more than 66 percent from outside the United States. IEEE claims to produce over 30% of the world's literature in the electrical, electronics, and computer engineering fields, publishing approximately 200 peer-reviewed journals and magazines. IEEE publishes more than 1,700 conference proceedings every year. The published content in these journals as well as

1204-582: The United States government. On February 26, 2022, the chair of the IEEE Ukraine Section, Ievgen Pichkalov, publicly appealed to the IEEE members to "freeze [IEEE] activities and membership in Russia" and requested "public reaction and strict disapproval of Russia's aggression" from the IEEE and IEEE Region 8. On March 17, 2022, an article in the form of Q&A interview with IEEE Russia (Siberia) senior member Roman Gorbunov titled "A Russian Perspective on

1247-769: The ViaSat 1, 2, and 3 satellites among others; in low Earth orbit (LEO) by the SpaceX Starlink system and the Iridium Next satellite series; it is also used in medium Earth orbit (MEO) by the SES O3b system; and the James Webb Space Telescope . Planned future satellite projects using the K a -band include Amazon 's Project Kuiper satellite internet constellation in LEO, SES 's multi-orbit satellite internet system of

1290-608: The War in Ukraine" was published in IEEE Spectrum to demonstrate "the plurality of views among IEEE members" and the "views that are at odds with international reporting on the war in Ukraine". On March 30, 2022, activist Anna Rohrbach created an open letter to the IEEE in an attempt to have them directly address the article, stating that the article used "common narratives in Russian propaganda" on

1333-580: The beam to feel an intense burning pain, as if their skin is going to catch fire. The military version had an output power of 100 kilowatts (kW), and a smaller law enforcement version, called Silent Guardian that was developed by Raytheon later, had an output power of 30 kW. Clothing and other organic materials are transparent to millimeter waves of certain frequencies, so a recent application has been scanners to detect weapons and other dangerous objects carried under clothing, for applications such as airport security. Privacy advocates are concerned about

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1376-567: The content from several hundred annual conferences sponsored by the IEEE are available in the IEEE Electronic Library (IEL) available through IEEE Xplore platform, for subscription-based access and individual publication purchases. In addition to journals and conference proceedings, the IEEE also publishes tutorials and standards that are produced by its standardization committees. The organization also has its own IEEE paper format. IEEE has 39 technical societies, each focused on

1419-507: The equipment that manipulates them, the techniques of geometric optics can be used. Diffraction is less than at lower frequencies, although millimeter waves can be diffracted by building edges. At millimeter wavelengths, surfaces appear rougher so diffuse reflection increases. Multipath propagation , particularly reflection from indoor walls and surfaces, causes serious fading. Doppler shift of frequency can be significant even at pedestrian speeds. In portable devices, shadowing due to

1462-535: The human body is a problem. Since the waves penetrate clothing and their small wavelength allows them to reflect from small metal objects they are used in millimeter wave scanners for airport security scanning. This band is commonly used in radio astronomy and remote sensing . Ground-based radio astronomy is limited to high altitude sites such as Kitt Peak and Atacama Large Millimeter Array ( ALMA ) due to atmospheric absorption issues. Satellite-based remote sensing near 60 GHz can determine temperature in

1505-444: The millimeter wave bands include point-to-point communications, intersatellite links , and point-to-multipoint communications . In 2013 it was speculated that there were plans to use millimeter waves in future 5G mobile phones. In addition, use of millimeter wave bands for vehicular communication is also emerging as an attractive solution to support (semi-)autonomous vehicular communications. Shorter wavelengths in this band permit

1548-517: The net result is greater frequency reuse , and higher density of users. The high usable channel capacity in this band might allow it to serve some applications that would otherwise use fiber-optic communication or very short links such as for the interconnect of circuit boards. Millimeter wave radar is used in short-range fire-control radar in tanks and aircraft, and automated guns ( CIWS ) on naval ships to shoot down incoming missiles. The small wavelength of millimeter waves allows them to track

1591-403: The stream of outgoing bullets as well as the target, allowing the computer fire control system to change the aim to bring them together. With Raytheon the U.S. Air Force has developed a nonlethal antipersonnel weapon system called Active Denial System (ADS) which emits a beam of millimeter radio waves with a wavelength of 3 mm (frequency of 95 GHz). The weapon causes a person in

1634-541: The technology exists to extend the search area to as far as 50 meters beyond the scanning area which would allow security workers to scan a large number of people without their awareness that they are being scanned. Recent studies at the University of Leuven have proven that millimeter waves can also be used as a non-nuclear thickness gauge in various industries. Millimeter waves provide a clean and contact-free way of detecting variations in thickness. Practical applications for

1677-519: The technology focus on plastics extrusion , paper manufacturing , glass production and mineral wool production . Low intensity (usually 10 mW/cm or less) electromagnetic radiation of extremely high frequency may be used in human medicine for the treatment of diseases . For example, "A brief, low-intensity MMW exposure can change cell growth and proliferation rates, activity of enzymes , state of cell genetic apparatus, function of excitable membranes and peripheral receptors." This treatment

1720-410: The top end of the band the waves are attenuated to zero within a few meters. Absorption by humidity in the atmosphere is significant except in desert environments, and attenuation by rain ( rain fade ) is a serious problem even over short distances. However the short propagation range allows smaller frequency reuse distances than lower frequencies. The short wavelength allows modest size antennas to have

1763-400: The use of smaller antennas to achieve the same high directivity and high gain as larger ones in lower bands. The immediate consequence of this high directivity, coupled with the high free space loss at these frequencies, is the possibility of a more efficient use of frequencies for point-to-multipoint applications. Since a greater number of highly directive antennas can be placed in a given area,

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1806-423: The use of this technology because, in some cases, it allows screeners to see airport passengers as if without clothing. The TSA has deployed millimeter wave scanners to many major airports. Prior to a software upgrade the technology did not mask any part of the bodies of the people who were being scanned. However, passengers' faces were deliberately masked by the system. The photos were screened by technicians in

1849-553: Was necessary for this purpose, and the scope was broadened. In addition to soliciting and administering unrestricted funds, the foundation also administers donor-designated funds supporting particular educational, humanitarian, historical preservation, and peer recognition programs of the IEEE. As of the end of 2014, the foundation's total assets were nearly $ 45 million, split equally between unrestricted and donor-designated funds. In May 2019, IEEE restricted Huawei employees from peer reviewing papers or handling papers as editors due to

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