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Iridium
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Iridium is a mobile-satellite service (MSS) system that was first licensed by the FCC in 1995, and began commercial service in 1998.
Iridium utilizes an FDMA/TDMA Time Division Duplex (TDD) access technology, so that the same frequency band is used for both the user uplink and downlink transmissions, on a time-shared basis. It shares a portion of its spectrum (1617.775-1618.725 MHz) with Globalstar, which has mobile uplinks to its own MSS system in the 1610-1618.725 MHz band.
Each Iridium user uplink/downlink channel has a bandwidth of 31.5 kHz and is separated in frequency by 41.67 kHz to allow for Doppler shift. A single Iridium TDMA frame is 90 ms long, which begins with 22.48 ms guard time, followed by four user uplink and four user donwlink time slots (8.28 ms burst time each, separated by small guard times).
A good discussion of the Iridium system architecture, constellation design, and multi-access scheme can be found in chapter 2 of the thesis by Abdul Jabbar (link below).
In February 2013, Iridium was granted authority by the FCC to provide aeronautical mobile-satellite (route) service (AMS(R)S) in the 1618.725-1626.5 MHz portion of its spectrum, limited to oceanic, polar, and remote regions. According to the FCC, "for purposes of this authorization, we consider oceanic regions to be those beyond 12 nautical miles from the baselines of the coastal states." Authorization for remote areas of other territories is contingent upon completing the agreement-seeking process under 5.367 of the ITU Radio Regulations.
At the end of 2012, Iridium reported approximately 368,000 subscribers. The company plans to launch a new generation of satellites, Iridium Next, beginning in 2015.
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Frequency Bands |
| Band | Use | Service | Table |
| 1617.775 - 1626.5 MHz | Iridium (user terminal uplinks and downlinks) | Mobile-satellite | N |
| 1618.725 - 1626.5 MHz | Iridium AMS(R)S | ARMR | N |
| 19.1 - 19.6 GHz | Iridium satellite gateway downlinks | Fixed-satellite | N |
| 22.55 - 23.55 GHz | Iridium inter-satellite links | Inter-satellite | N |
| 29.1 - 29.3 GHz | Iridium gateway uplinks | Fixed-satellite | N |
External Links:
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DISH Network
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DISH network uses the 12.2-12.7 GHz band for its direct broadcast satellite TV service. This is the band received by customers who subscribe to the DISH Network service. The satellites also transmit relatively narrowband (300 kHz-1 MHz) telemetry, tracking, and control (TT&C) signals in this band, primarily in the lower and upper few MHz of the band.
DISH uses 17.3-17.8 GHz for feeder links (uploading the TV signals from the ground to the satellites), from earth stations located in Cheyenne, WY, and Gilbert, AZ. It also sends relatively narrowband (36 kHz-800 kHz) telemetry, tracking, and control signals to the satellites from these earth stations, primarily in the lower and upper few MHz of the band.
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Frequency Bands |
| Band | Use | Service | Table |
| 12.2 - 12.7 GHz | DISH Network direct broadcast TV service & affiliated TT&C signals | BS | N |
| 17.3 - 17.8 GHz | DISH Network feeder links and TT&C signals | Fixed-satellite | N |
External Links:
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Satellite Digital Audio Radio Service (SDARS) (Sirius & XM)
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Sirius and XM, which are now one company, use this band to transmit digital radio from their satellites and also from ground-based transmitters (terrstrial repeaters) that fill in coverage gaps due to building and terrain blockage of the satellite signals.
According to the FCC (FCC 10-82), "The Commission's rules define SDARS - commonly known as "satellite radio" – as "[a] radiocommunication service in which audio programming is digitally transmitted by one or more space stations directly to fixed, mobile, and/or portable stations, and which may involve complementary repeating terrestrial transmitters, telemetry, tracking and control facilities." Thus, SDARS is primarily a satellite-delivered service in which programming is sent directly from satellites to subscriber receivers either at a fixed location or in motion. Because a direct line of sight is generally required in order to receive an acceptable satellite signal, ground-based terrestrial repeaters are used in many areas to re-transmit the same signals provided by satellites directly to subscribers in order to maintain adequate signal power. These areas include "urban canyons" between tall buildings, heavily foliaged areas, tunnels, and other places where obstructions could limit satellite visibility or cause multipath interference from reflected signals.
"Licenses to provide SDARS within the United States were awarded by auction in early April, 1997. The two winners of the auction – XM and Sirius – were each assigned 12.5 megahertz of spectrum for their exclusive use on a primary basis. XM and Sirius launched their satellites and began commercial operations in 2001 and 2002, respectively. As of March 31, 2010, Sirius XM reported it had 18,944,199 subscribers in the conterminous United States.
"On August 5, 2008, the Commission approved the merger of XM and Sirius, which have subsequently combined to form a merged entity called "Sirius XM." In the merger proceeding, the Commission found that significant engineering differences in the XM and Sirius infrastructures make integration of the two systems difficult in the short term. In addition, the Commission noted that XM and Sirius had each invested significantly in their existing infrastructure, with the expectation of operating this infrastructure for years to come. Thus, despite the merger of the two companies, the XM and Sirius satellite and repeater infrastructures will operate as separate, legacy systems, at least in the near term.
"Sirius XM offers hundreds of channels of music, entertainment, news, and sports programming on the Sirius and XM satellite radio networks, as well as weather and data information services for maritime, aeronautical, and other purposes. SDARS radio receivers are used in cars, trucks, boats, aircraft, and homes – and are available for portable use..."
Acccording to SiriusXM, their satellite signals cover the 48 contiguous states, and 200 miles "off shore."
Historical Information on SDARS
The following is historical information on SDARS from Benn Kobb's 2001 book Wireless Spectrum Finder. That book is now (c) SpectrumWiki.com:
*****
The principal worldwide band for audio broadcasting direct to the public from satellites (Broadcasting-Satellite Service (Sound) or BSS) is the so-called L-band, 1452—1492 MHz.
That band falls within aeronautical test telemetry spectrum in the U.S. (see 1435—1525 MHz).
As an alternative, the International Telecommunication Union (ITU) allocated the S-band, 2310—2360 MHz, for domestic satellite audio broadcasting in the U.S. Other nations, especially Canada, criticized this action as detrimental to the realization of a uniform worldwide service in the L-band.
The ITU also allocated 2520—2670 MHz for BSS national and regional systems for community reception. (India and Mexico also are authorized to use the S-band for BSS.)
Against ferocious opposition from conventional broadcasters, the FCC eventually allocated 2320—2345 MHz to satellite Digital Audio Radio Services (SDARS or DARS). “Satellite DARS will provide continuous radio service of compact disc quality for all listeners and will offer an increased choice of over-the-air audio programming,” the FCC said.
No other significant terrestrial U.S. users are in the S-band, but adjacent countries operate terrestrial fixed point-to-point, fixed point-to-multipoint, and aeronautical mobile telemetry systems in the band. Satellite DARS operators must take precautions to avoid interference with the systems of other nations.
Sirius and XM
There are two SDARS licensees : Sirius Satellite Radio (2320—2332.5 MHz), formerly Satellite CD Radio and XM Satellite Radio (2332.5—2345 MHz), formerly American Mobile Radio.
These companies won their licenses by bidding $83 million and $89 million, respectively, at an April 1997 auction. The FCC concluded that only enough spectrum existed in the S-band for two SDARS licensees of 12.5 MHz each. The FCC requires that SDARS receivers be capable of picking up broadcasts from both of the licensees.
The licensees must deploy hundreds of terrestrial repeaters, ground transmitters that relay broadcasts from satellites. Most of the gap-fillers will be in urban areas where obstructions inhibit satellite reception.
Sirius will use three satellites in inclined elliptical orbits will offer a service directed mainly to vehicle radios. Sirius-1 and Sirius-2 had been launched at this writing. The major investors in Sirius include Ford and Loral.
XM will use two geostationary satellites (officially designated “Rock” and “Roll”) that are directed both to vehicle and portable radios. XM’s major investors include GM and its DirecTV business; Clear Channel Communications; and Liberty Media, in addition to its founder, Motient Corp., formerly American Mobile Satellite Corp.
Uplink stations in 7.025—7.075 GHz feed these satellites. They use frequencies in the S-band in 3.7—4.2 GHz, and 5.925—6.425 GHz for telemetry and control, operation during transfer to final orbit, and for contingency purposes.
Other SDARS-Related Issues
Sirius and XM might have faced competition from SDARS service in the Wireless Communications Service (WCS) band. A group of WCS licensees applied for permission to use their licenses to provide SDARS (see 2305—2310 MHz). They later abandoned the idea.
The FCC licensed, originally on an experimental basis only, the WorldSpace SDARS system to broadcast in the L-band (see 1435—1525 MHz). It later granted full authorization to the Washington, D.C.-based WorldSpace, but does not permit the company to serve U.S. audiences.
NASA’s Goldstone Solar System Radar operates at 2320 MHz and 8.56 GHz in the Mojave Desert northeast of Los Angeles. Scientists used it to observe Comet Hyakutake when it passed within 9.3 million miles of Earth in 1996.
SDARS interference is expected to make radar astronomy operations at 2320 MHz “nearly impossible,” according to NASA’s Jet Propulsion Laboratory.
The 2310—2390 MHz spectrum is one of many restricted bands in which the FCC Part 15 rules permit unlicensed devices to emit only very low level emissions.
***** (End of historical information from Wireless Spectrum Finder)
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NTIA Spectrum Use Summary
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The federal agencies use this band for fixed point-to-point microwave communication systems for national and military test range communications, and the remote transmission of radar video and other data for functions such as weather, vessel traffic control in harbor areas, and hydroelectric grid power management. This includes the Federal Aviation Administration use of this band for fixed point-to-point microwave communications networks to connect remote long-range aeronautical radionavigation radars to air traffic control centers.
The National Aeronautics and Space Administration and the National Oceanographic and Atmospheric Administration use the 6425-7250 MHz band for passive sensing of the Earth from space using microwave radiometers to obtain measurements of sea surface temperature which is a key component in weather forecasting and climatological studies. This band is used in conjunction with passive sensing bands around 10.6, 18.7, 23.8 and 36 GHz to obtain several important climatological parameters.
The NTIA does not issue information on the use of specific band segments in the 7/8 GHz band for fixed links, but the following information is available in a 2000 NTIA Report (NTIA Report 00-378) regarding government fixed service use in the 7125-8500 MHz range:
The FAA has 4,010 fixed assignments, including the radio communications link (RCL) system, a nationwide network used to connect air traffic controllers with communications and radar data from remote radar sites. The Air Force has 710 fixed assignments, used to support a large number of activities on numerous test and training ranges. The Navy has 800 fixed assignments, used mainly in voice and data links, ground forces communication, and land-line back up.
The Army has 450 fixed assignments, used for video scoring, closed circuit TV (security), point-to-point communications training, and for administrative traffic.
DOE has 1,200 fixed assignments used for system control and data acquisition (SCADA) for electric power distribution networks, perimeter security surveillance, laboratory telecommunication systems, and test site surveillance. Justice has 400 fixed assignments, used for fixed backbone nets used in law enforcement communications.
The Coast Guard has 160 fixed assignments, used to relay maritime radar and
communications needed for safety and navigation purposes in harbors and other critical locations. TVA has 140 fixed assignments, used for SCADA for electric power distribution systems.
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Frequency Bands |
| Band | Use | Service | Table |
| 7125 - 7145 MHz | NTIA Spectrum Use Summary | - | F |
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NASA Tracking and Data Relay Satellite System (TDRSS)
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According to NASA:
The Tracking and Data Relay Satellites (TDRS) comprise the communication satellite component of the Tracking and Data Relay Satellite System (TDRSS). TDRSS is a communication signal relay system which provides tracking and data aquisition services between low-earth orbiting spacecraft and control and/or data processing facilities. The system is capable of transmitting to and receiving data from spacecraft over at least 85% of the spacecraft's orbit.
The TDRSS space segment consists of six on-orbit Tracking and Data Relay Satellites located in geosynchronous orbit. Three TDRSs are available for operational support at any given time. The operational spacecraft are located at 41°, 174° and 275° West longitude. The other TDRSs in the constellation provide ready backup in the event of a failure to an operational spacecraft and, in some specialized cases, resources for target of opportunity activities.
The TDRSS ground segment is located near Las Cruces, New Mexico, known as the White Sands Complex. Forward data is uplinked from the ground segment to the TDRS and from the TDRS to the spacecraft. Return data is downlinked from the spacecraft via the TDRS to the ground segment and then on to the designated data collection location.
The Tracking and Data Relay Satellite (TDRS) Project is providing follow-on and replacement spacecraft necessary to maintain and expand the Space Network. The contract to build three additional TDRS spacecraft, known as TDRS K, L, and M, was awarded to Boeing Space Systems in December 2007. TDRS K launched January 30, 2013, and TDRS L launched January 23, 2014. TDRS M's launch readiness date is scheduled for 2015. The contract also has options for one additional spacecraft, TDRS N. In addition to building the TDRS K, L, and M spacecraft, the contract also includes the modifications to the White Sands Complex (WSC) ground system required to support these new spacecraft.
The TDRS Project, established in 1973, is responsible for the development, launch, and on-orbit test and calibration of TDRS spacecraft. There have been four procurements of TDRS spacecraft, which include the Basic Program (TDRS F1-F6), the Replacement Program (TDRS F7), the TDRS H,I,J Program, and the TDRS K,L,M Program. TDRS Flight 7 was a replacement for Flight 2, which was lost aboard Challenger in 1986. The first seven spacecraft (TDRS F1-F7) are referred to as the First Generation, the H,I,J series are called the Second Generation, and the K,L,M series are known as the Third Generation. TDRS F1-7 spacecraft were built by TRW (now Northrop Grumman) in Redondo Beach, CA. The TDRS F8-10 (H,I,J) spacecraft were built by Hughes (now Boeing) in El Segundo, CA.
The NASA Space Network consists of the on-orbit telecommunications TDRS satellites, placed in geosynchronous orbit, and the associated TDRS ground stations, located in White Sands, New Mexico and Guam. The TDRS constellation is capable of providing nearly continuous high bandwidth (S, Ku, and Ka band) telecommunications services for expandable launch vehicles and user spacecraft in low Earth orbit. Examples include: the Hubble Space Telescope, the Earth Observig Fleet and the International Space Station. The TDRS System is a basic agency capability and a critical national resource.
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Paired Frequency Bands |
| Paired Bands | Use | Service | Table |
| 2025.8 - 2117.9 MHz | S-band Single Access (TDRS transmit) | Space Operation | F |
| 2200 - 2300 MHz | S-band Single Access (TDRS receive) | Space Research (space-to-Earth) | F |
| 2103.4 - 2109.4 MHz | S-band Multiple Access (TDRS transmit) | Space Operation | F |
| 2285 - 2290 MHz | S-band Multiple Access (TDRS receive) | Space Operation (space-to-Earth) | F |
| 13.4 - 14.05 GHz | TDRS downlink | Space Research | F |
| 14.6 - 15.25 GHz | TDRS uplink | Space Research (Earth-to-space) | F |
| 13.75 - 13.8 GHz | Ku-band Single Access (TDRS transmit) | Space Operation | F |
| 14.891 - 15.116 GHz | Ku-band Single Access (TDRS receive) | Space Research (space-to-Earth) | F |
Frequencies |
| Frequency | Bandwidth | Use | Service | Table |
| 2036 MHz | - | TDRS command uplink | Space Operation | F |
| 2211 MHz | - | TDRS telemetry downlink | Space Operation | F |
| 13.731 GHz | - | TDRS telemetry downlink | Space Operation | F |
| 14.785 GHz | - | TDRS command uplink | Space Operation | F |
| 15.15 GHz | - | TDRS reference frequency signal uplink | Space Operation | F |
Frequency Bands |
| Band | Use | Service | Table |
| 25.25 - 27.5 GHz | Ka-band Single Access (TDRS receive) | Space Research | F |
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Defense Satellite Communication System 3 (DSCS III)
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According to the U.S. Space Force:
Defense Satellite Communications System (DSCS) constellation provides long haul communications to users worldwide through contested environments.
DSCS supports: the defense communications system, the military’s ground mobile forces, airborne terminals, ships at sea, and Department of Defense (DOD).
The first DSCS III satellite was launched in October 1982. The final DSCS III satellite, B6, was launched in August 2003. In all, DSCS III successfully launched 14 satellites, six of which are still operational and continue to be used in various capacities, from operational communications in Southwest Asia to research and development of ground-based support capabilities.
Space and Missile Systems Center (SMC), Los Angeles Air Force Base, Calif., sustains the DSCS Space Segment contract.
DSCS III satellites support globally distributed DOD and national security users. Modifications made to these satellites will provide substantial capacity improvements through higher power amplifiers, more sensitive receivers, and additional antenna connectivity options. The DSCS communications payload includes six independent Super High Frequency (SHF) transponder channels. Three receive and five transmit antennas provide selectable options for Earth coverage, area coverage and/or spot beam coverage. A special purpose single-channel transponder is also on board.
DSCS satellites provide the capabilities needed for effective implementation of worldwide military communications. It can adapt rapidly to dynamic operating conditions and perform under stressed environments. DSCS operates with large or small terminals. DSCS’s independent channels group users by operational needs or geographical location by allocating receiver sensitivity and transmitter power, thus providing maximum efficiency.
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Paired Frequency Bands |
| Paired Bands | Use | Service | Table |
| 7250 - 7750 MHz | DSCS III downlink | Mobile-satellite | F |
| 7900 - 8400 MHz | DSCS III uplink | Mobile-satellite | F |
Frequencies |
| Frequency | Bandwidth | Use | Service | Table |
| 7600 MHz | - | DSCS III Beacon (A series satellites) | Mobile-satellite | F |
| 7604.705882 MHz | - | DSCS III Beacon (B series satellites) | Mobile-satellite | F |
| 8005.146484 MHz | - | DSCS III Channel 1 command uplink | Mobile-satellite | F |
| 8370.146484 MHz | - | DSCS III Channel 5 command uplink | Mobile-satellite | F |
External Links:
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ViaSat-1 Ka-band Satellite
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ViaSat uses this spectrum for its Ka-band direct-to-consumer broadband Internet service, under the trade name "exede." The ViaSat-1 satellite was launched from Baikonur on October 19th, 2011, and entered commercial service on January 16th, 2012.
The satellite downlinks and uplinks use both right- and left-hand circular polarizations from a geostationary orbit at 115.1 deg west longitude.
ViaSat-1 has 72 user beams, of which 63 serve the U.S. Nine beams serve Canada.
User terminals utilize a dish of 0.695 m (about 27") maximum diameter, and will uplink using carriers between 625 kHz and 10 MHz wide using max EIRP between 47.2-50.3 dBW. The antennas have transmit gain of about 44 dBi, and receive gain of about 40 dBi. ViaSat is authorized for up to 250,000 such terminals in the continental U.S., operating under the callsign E120026.
The satellite downlink bandwidth is between 52-416 MHz.
As of March 2013, ViaSat claimed 512,000 customers. They have also announced plans for the ViaSat-2 satellite, to be launched in mid-2016, which will have 2.5 times the capacity of ViaSat-1, and will have a single beam that covers the continental U.S., Mexico, most of Canada, portions of Central America and the Caribbean, and the North Atlantic over to the western edge of Europe.
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Frequency Bands |
| Band | Use | Service | Table |
| 18.3 - 18.8 GHz | ViaSat-1 downlink | Fixed-satellite | N |
| 18.8 - 19.3 GHz | ViaSat-1 downlink | Fixed-satellite | N |
| 19.7 - 20.2 GHz | ViaSat-1 downlink | Fixed-satellite | N |
| 28.1 - 28.6 GHz | ViaSat-1 uplink | Fixed-satellite | N |
| 28.6 - 29.1 GHz | ViaSat-1 uplink | Fixed-satellite | N |
| 29.5 - 30 GHz | ViaSat-1 uplink | Fixed-satellite | N |
External Links:
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Unlicensed bands
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Although these bands are allocated for ISM use, e.g. microwave ovens and industrial equipment, a major use has been unlicensed (Part 15) systems such as Wi-Fi, Bluetooth, and ZigBee. In the period 1995-2005, most of the cordless phones marketed in the US were in the 902-928 MHz band, but conflicts with the other uses and availability of DECT equipment has greatly decreased sales of 902-928 MHz cordless phones.
The rules for these bands sprung from FCC Docket 81-413 which sought to end an implicit prohibition of spread spectrum/CDMA technology that resulted from a focus on FDMA spectrum uses. This resulted in rules adopted in 1985 that allow unlicensed spread spectrum systems to use these bands for almost any possible application subject to a 1W power limit and a power spectral density limit. Initial applications, however, were limited to frequency hopping and "direct sequence" modulations, the latter being subject to ill-defined spreading and processing gain requirements.
An FCC rulemaking in 2002, in ET Docket No. 99-231, dropped the spreading and processing gain requirements, and permitted any digital modulation that meets the power and power spectral density limits. The immediate effect was to authorize Wi-Fi products under standard IEEE 802.11g. Subsequent Wi-Fi standards, including n and ac, were eligible for certification with no further rule changes.
Bluetooth is authorized under the original 1985 frequency hopping provisions.
The 2400 and 5800 MHz bands are used for Wi-Fi.
A good history is "The Innovation Journey of Wi-Fi: The Road To Global Success" by Wolter Lemstra, Vic Hayes, John Groenewegen; Cambridge University Press, 2010.
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Frequency Bands |
| Band | Use | Service | Table |
| 902 - 928 MHz | 900 MHz unlicensed band | - | - |
| 2400 - 2483.5 MHz | Unlicensed band (commonly used by Wi-Fi) | - | - |
| 5725 - 5850 MHz | Unlicensed band (commonly used by Wi-Fi) | - | - |
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Industrial, Scientific, and Medical Devices (ISM, FCC Part 18)
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Part 18 (section 18.301) of the FCC rules designate certain bands for high-power Industrial, Scientific, and Medical (ISM) devices. These devices generate significant radio energy, but not for telecommunications purposes. Examples includes microwave ovens, industrial heaters, medical diathermy, jewelry cleaners, and RFID tags.
ISM devices may be operated in most frequency bands subject to strict power limits, but are allowed unlimited power in these eleven specially-designated ISM bands.
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Wi-Fi
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Wi-Fi utilizes various channels in the 2.4 and 5.8 GHz band (worldwide), and the 3.6 GHz band (U.S. only). For a list of which channels are available in which regions, refer to the Wikipedia article.
Wi-Fi is a trademark permitted for devices that are based upon a published standard of the IEEE 802.11 committee and that have been certified by the Wi-Fi Alliance. Wi-Fi is presently incorporated in about three billion devices. Wireless cash registers were one of the earliest applications of what is now Wi-Fi.
Wi-Fi devices operate on an unlicensed basis, generally meaning they cannot cause interference to licensed services, and must accept any interference caused to them. Wi-Fi shares bands with other unlicensed or ISM devices, such as cordless phones at 2.4 and 5.8 GHz and microwave ovens at 2.4 GHz.
Some of the key patents related to Wi-Fi are credited (in the courts at least) to the Commonwealth Scientific and Industrial Research Organisation (CSIRO) in Australia, which has collected over $400 million in royalties and legal settlements over patent rights.
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Frequency Bands |
| Band | Use | Service | Table |
| 2400 - 2500 MHz | Wi-Fi (802.11b, 802.11g, 802.11n) | - | - |
| 3655 - 3700 MHz | Wi-Fi (802.11y) (U.S. only) | - | - |
| 4910 - 5845 MHz | Wi-Fi (802.11a, 802.11h, 802.11j, 802.11n) (non-contiguous) | - | - |
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Airport Surface Detection Radars (ASDE-X)
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The band 9000-9200 MHz is used for radars that comprise one component of the FAA's Airport Surface Detection Equipment, Model X (ADSE-X) system. The 21-24 foot long radar antenna is usually installed on top of the control tower or a remote tower, and rotates at a rapid rate of once each second. ASDE-X data can complement data obtained by a legacy version, ASDE-3, that operates in the Ku band (15.7-16.2 GHz). An article on Gizmodo.com notes that ADSE-3 "has one fatal flaw--it thinks raindrops are incoming jets and goes nuts during downpours. The ASDE Model X, however, monitors runways rain or shine."
According to the FAA (2010 information):
The potential for collisions on airport runways and taxiways increases every year as airports become busier. To combat the impact of this trend, the FAA is deploying ASDE-X, a new runway-safety tool.
ASDE-X enables air traffic controllers to detect potential runway conflicts by providing detailed coverage of movement on runways and taxiways. ASDE-X collects data from a variety of sources to track vehicles and aircraft on the airport movement area and obtain identification information from aircraft transponders.
The ASDE-X data comes from surface movement radar located on the air traffic control tower or remote tower, multilateration sensors, ADS-B (Automatic Dependent Surveillance-Broadcast) sensors, the terminal automation system, and aircraft transponders. By fusing the data from these sources, ASDE-X is able to determine the position and identification of aircraft and transponder-equipped vehicles on the airport movement area, as well as aircraft flying within five miles of the airport.
Controllers in the tower see this information presented as a color display of aircraft and vehicle positions overlaid on a map of the airport’s runways, taxiways and approach corridors. The system creates a continuously updated map of the airport movement area that controllers can use to spot potential collisions. This technology is especially helpful to controllers at night or in bad weather when visibility is poor.
ASDE-X Safety Logic (AXSL) is an enhancement to the situational awareness provided to air traffic controllers by ASDE-X. AXSL uses surveillance information from ASDE-X to determine if the current or projected positions and movements of aircraft or vehicles that are being tracked present a potential collision situation. Visual and audible alerts are provided to the controllers that include critical information about the targets, such as aircraft identification and where aircraft and vehicles are on the surface.
The first use ASDE-X was at General Mitchell International Airport in Milwaukee, Wis. in October 2003. The FAA recently accelerated the ASDE-X schedule and now projects that all systems will be deployed by the end of 2010 – one year earlier than originally anticipated.
ASDE-X Deployment Sites
The 35 major airports that will receive, or have already received, ASDE-X include:
(* Indicates ASDE-X is operational at these sites)
Baltimore-Washington International Thurgood Marshall Airport (Baltimore, MD)
Boston Logan International Airport (Boston, MA)*
Bradley International Airport (Windsor Locks, CT)*
Chicago Midway Airport (Chicago, IL)*
Chicago O’Hare International Airport (Chicago, IL)*
Charlotte Douglas International Airport (Charlotte, NC)*
Dallas-Ft. Worth International Airport (Dallas, TX)*
Denver International Airport (Denver, CO)*
Detroit Metro Wayne County Airport (Detroit, MI)*
Ft. Lauderdale/Hollywood Airport (Ft. Lauderdale, FL)*
General Mitchell International Airport (Milwaukee, WI)*
George Bush Intercontinental Airport (Houston, TX)*
Hartsfield-Jackson Atlanta International Airport (Atlanta, GA)*
Honolulu International –Hickam Air Force Base Airport (Honolulu, HI)*
John F. Kennedy International Airport (Jamaica, NY)*
John Wayne-Orange County Airport (Santa Ana, CA)*
LaGuardia Airport, (Flushing, NY)
Lambert-St. Louis International Airport (St. Louis, MO)*
Las Vegas McCarran International Airport (Las Vegas, NV)
Los Angeles International Airport (Los Angeles, CA)*
Louisville International Airport-Standiford Field (Louisville, KY)*
Memphis International Airport (Memphis, TN)
Miami International Airport (Miami, FL)*
Minneapolis St. Paul International Airport (Minneapolis, MN)*
Newark International Airport (Newark, NJ)*
Orlando International Airport (Orlando, FL)*
Philadelphia International Airport (Philadelphia, PA)*
Phoenix Sky Harbor International Airport (Phoenix, AZ)*
Ronald Reagan Washington National Airport (Washington, DC)
San Diego International Airport (San Diego, CA)*
Salt Lake City International Airport (Salt Lake City, UT)*
Seattle-Tacoma International Airport (Seattle, WA)*
Theodore Francis Green State Airport (Providence, RI)*
Washington Dulles International Airport (Chantilly, VA)*
William P. Hobby Airport (Houston, TX)*
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Frequency Bands |
| Band | Use | Service | Table |
| 9000 - 9200 MHz | Airport Surface Detection Equipment, Model X (ASDE-X) | Aeronautical Radionavigation | - |
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802.11ad (WiGig)
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IEEE 802.11ad is an amendment to the 802.11 standard that enables multi-gigabit wireless communications in the 60 GHz band. The WiGig specification was contributed to the IEEE 802.11ad standardization process, and was confirmed in May 2010 as the basis for the 802.11ad draft standard.
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Channelized Bands |
| Band | Channel | Use | Service | Table |
| 57.24 - 59.4 GHz | 1 | 802.11ad channel 1: USA, Canada, Korea, EU | - | N |
| 59.4 - 61.56 GHz | 2 | 802.11ad channel 2: USA, Canada, Korea, EU, China, Japan | - | N |
| 61.56 - 63.72 GHz | 3 | 802.11ad channel 3: USA, Canada, Korea, EU, China, Japan | - | N |
| 63.72 - 65.88 GHz | 4 | 802.11ad channel 4: EU, Japan | - | N |
External Links:
Associated Files:
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Proposed Air-Ground Broadband for Passengers Aboard Aircraft
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The FCC has proposed the establishment of a new air-ground mobile broadband service in the 14.0-14.5 GHz band. The current primary allocation is to the Fixed Satellite Service. The FCC proposes to achieve compatibility through “spatial diversity” rules, which would limit the directions in which antennas can point. Since the 14.0-14.5 GHz band is used for sending transmissions from the Earth towards satellites orbiting over the equator, U.S. earth stations all point south, more or less. Antennas in the proposed system would point north (in the case of ground stations) or downwards (in the case of the antennas on the aircraft), which should reduce their interference with satellite users.
The following information is edited from the FCC's Notice of Proposed Rulemaking,FCC 13-66:
We propose to establish a new, terrestrial-based air-ground mobile broadband service with aircraft in the 14.0-14.5 GHz band. The service would provide multi-gigabit broadband connectivity to aircraft flying within the contiguous United States. The service is intended for the business and personal use of passengers aboard aircraft, and will have no role in aeronautical operations or as a safety of life and property service.
The 14.0-14.5 GHz band is allocated on a primary basis to the FSS as an uplink (Earth-to-space) band for geostationary orbit (GSO) FSS operations. The air-ground mobile broadband service would operate on a secondary basis to GSO satellite systems and future non-geostationary orbit (NGSO) satellite systems, and on a co-secondary basis with the National Aeronautics and Space Administration (NASA) Tracking and Data Relay Satellite System (TDRSS) that operates under a Federal Fixed Service (FS) and Mobile Service (MS) allocation. In addition to coordinating with NASA TDRSS in the 14.0-14.2 GHz band, we propose that air-ground mobile broadband would also be required to coordinate with Radio Astronomy Service (RAS) users in the 14.47-14.5 GHz band, in accordance with the procedures set forth for other services in this band. To implement this service, we propose to amend Part 2 of the rules to add a secondary allocation in the non-Federal Aeronautical Mobile Service (AMS) for air-ground mobile broadband in the 14.0-14.5 GHz band.
We propose that under the rules we implement for the 14.0-14.5 GHz band to support the new allocation, we would require a licensee to use this spectrum for air-ground mobile broadband only. We also seek comment regarding the appropriate regulatory framework for the proposed provision of service. We seek comment on our proposal to classify the services as Commercial Mobile Radio Service (CMRS) given the proposed air-ground use of the spectrum. With respect to whether and how to apportion the spectrum, we seek comment on Qualcomm’s proposal to create two 250 megahertz licenses as well as on alternate approaches such as licensing the entire 500 megahertz of spectrum to a single licensee or dividing the spectrum into more than two blocks. Given the proposed air-ground use of the band, we propose to license the spectrum on a nationwide basis. We also seek comment on whether to adopt an open eligibility standard and whether to adopt any specific aggregation limits applicable to the initial licensing of the band.
To the extent that we adopt a geographic licensing scheme for the 14.0-14.5 GHz band, and permit the filing of mutually exclusive applications, we seek comment on a number of proposals relating to competitive bidding. We propose that the Commission conduct an auction in conformity with the general competitive bidding rules set forth in Part 1, Subpart Q, of the Commission’s rules, and seek comment regarding bidding credits for small businesses.
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Frequency Bands |
| Band | Use | Service | Table |
| 14 - 14.5 GHz | - | ARMR | N |
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Ligado Networks
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Ligado Networks, formerly LightSquared, formerly Mobile Satellite Ventures (MSV), operates space- and ground-based wireless services. The space services were originally provided using the MSAT-1 and MSAT-2 satellites in geostationary orbit, but now uses the Skyterra-1 satellite, also in GSO at the 101 deg W orbital slot. A second satellite, Skyterra-2, was planned, but is on hold due to the earlier LightSquared bankruptcy.
MSAT-1 was launched in 1996 operated by U.S. and Canadian companies, while MSAT-2, also referred to as AMSC-1 (for American Mobile Satellite Consortium), was launched in 1995 and operated by American companies. MSAT-1 was located at 106.5 W, and MSAT-2 was located at 101 W.
LightSquared originally desired to supplement its mobile-satellite service with an Ancillary Terrestrial Component (ATC) network comprised of up to 40,000 base stations in their 1525-1559 MHz band. However, concern over interference to the embedded base of GPS receivers operating just above 1559 MHz scuttled that idea after it had already been approved by the FCC. Lawsuits and bankruptcy soon followed. In 2016, Ligado filed a plan with the FCC, agreeing to move its ATC operations to the lower part of the band at
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Frequency Bands |
| Band | Use | Service | Table |
| 1530 - 1544 MHz | LightSquared MSAT-2 Satellite (space-to-Earth) | Mobile-satellite | N |
| 1545 - 1559 MHz | LightSquared MSAT-2 Satellite (space-to-Earth) | Mobile-satellite | N |
| 1631.5 - 1645.5 MHz | LightSquared MSAT-2 Satellite (Earth-to-space) | Mobile-satellite | N |
| 1646.5 - 1660.5 MHz | LightSquared MSAT-2 Satellite (Earth-to-space) | Mobile-satellite | N |
| 13 - 13.15 GHz | LightSquared MSAT-2 Satellite Feeder Links (Earth-to-space) | Fixed-satellite | N |
| 13.2 - 13.25 GHz | LightSquared MSAT-2 Satellite Feeder Links (Earth-to-space) | Fixed-satellite | N |
Frequencies |
| Frequency | Bandwidth | Use | Service | Table |
| 11.7005 GHz | - | LightSquared MSAT-2 Satellite TT&C (space-to-Earth) | Fixed-satellite | N |
| 11.701 GHz | - | LightSquared MSAT-2 Satellite TT&C (space-to-Earth) | Fixed-satellite | N |
| 14.005 GHz | - | LightSquared MSAT-2 Satellite TT&C (Earth-to-space) | Fixed-satellite | N |
| 14.4995 GHz | - | LightSquared MSAT-2 Satellite TT&C (Earth-to-space) | Fixed-satellite | N |
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SPN-43 Shipborne Radar
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The AN/SPN-43C is a U.S. Navy air traffic control (ATC) radar for large-deck amphibious ships that are capable of supporting flight operations. These vessels include aircraft carriers (CVN) and amphibious assault ships (LHA and LHD) that predominantly carry helicopters.
U.S. homeports for ships that carry the SPN-43 are Norfolk VA, San Diego CA, Bremerton WA, and Newport News VA. The SPN-43 is currently installed on 21 commissioned ships in the U.S. Navy. It may also be installed on some non-U.S. military ships.
Land-based testing and training sites for the SPN-43 are at St. Inigoes (Pax River) MD, Pascagoula MS, and Pensacola FL, per footnote US348.
The SPN-43 possesses the following technical characteristics:
-Modulation P0N (unmodulated pulses, no information transmitted)
-Tuning range 3500-3700 MHz
-Peak tx power into antenna: 1 MW (60 dBW)
-Antenna gain: 32 dBi
-Peak EIRP: 1.6 GW (92 dBW)
-Pulse width: 0.95 microseconds
-Pulse repetition rate: 1 kHz
-Duty cycle: 0.1%
-Transmit bandwidth: 1.6 MHz
-Antenna type: Rotating parabolic
-Beamwidth: 1.75 deg horizontal, 4.4 deg vertical (vertical fan beam, csc2 to 30 deg elevation)
-Polarization: Horizontal
-Antenna rotation rate: One revolution per 4 seconds
In the range 3650-3700 MHz, operation of the radar is only allowed more than 50 miles off shore.
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Frequency Bands |
| Band | Use | Service | Table |
| 3500 - 3700 MHz | SPN-43 shipborne air traffic control radar | Radiolocation | F |
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SPY-1 Shipborne Air Surveillance Radar
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The SPY-1 is a U.S. Navy phased array surveillance radar that is a component of the Aegis combat system. It is installed on guided missile cruisers (CG) and guided missile destroyers (DDG). Several variants of the SPY-1, including the -1A, -1B(V), -1D, and -1F are in service, modified to fit specific types of vessels. The -1F is not installed on any U.S. ships.
U.S. land-based test and training sites for the SPY-1 are at Moorestown, NJ, and Wallops Island, VA.
The SPY-1 possesses the following technical characteristics according to ITU-R Recommendation M.1465:
-Modulation: Q7N (angle-modulated, two or more digital channels, no information transmitted)
-Tuning range: 3100-3500 MHz
-Peak tx power into antenna: 4 – 6.4 MW (66 – 68 dBW)
-Antenna gain: 42 dBi
-Peak EIRP: 63 – 101 GW (108-110 dBW)
-Pulse width: 6.4 – 51.2 microseconds
-Pulse repetition rate: 0.152-6 kHz
-Duty cycle: 0.8-2.0%
-Tx bandwidth (-3 dB): 4 MHz
-Average EIRP (=peak EIRP x duty cycle): 504 MW – 2 GW (87-93 dBW)
-Minimum effective isotropic power spectral density: 126 W/Hz (51 dBm/Hz)
-Maximum effective power isotropic spectral density: 500 W/Hz (57 dBm/Hz)
-Antenna type: Phased array
-Beamwidth: 1.7 deg (azimuth and elevation)
-Polarization: Vertical
-Antenna rotation rate: N/A (electronically steered)
The SPY-1 is known to emit very high levels of out-of-band emissions outside of the 3100-3500 MHz band.
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Frequency Bands |
| Band | Use | Service | Table |
| 3100 - 3500 MHz | SPY-1 Shipborne Air Surveillance Radar | Radiolocation | F |
Associated Files:
SPY-1 phased array antenna panels on the guided missile destroyer USS Laboon, photographed in the Chesapeake Bay near Norfolk, Virginia.
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70/80/90 GHz Bands
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According to FCC document DA 16-974:
In 2003 the Commission adopted a Report and Order establishing service rules to promote non-Federal development and use of the “millimeter wave” spectrum in the 71-76 GHz, 81-86 GHz and 92-95 GHz bands on a shared basis with Federal Government operations. It modified those rules on reconsideration in 2005. The Commission adopted a flexible and innovative regulatory framework for the 70/80/90 GHz bands that allows for the issuance of an unlimited number of nonexclusive, nationwide licenses to non-Federal Government entities for a total of 12.9 gigahertz of spectrum allocated for commercial use. These licenses serve as a prerequisite for registering individual point-to-point links in a link registration system developed and managed by one or more third-party database managers. A licensee is not authorized to operate a link under its nationwide license until the link is both (1) coordinated with the National Telecommunications and Information Administration (NTIA) with respect to Federal Government operations and (2) registered as an approved link. The Report and Order noted that, in the past, the Commission had introduced market forces into the frequency coordination process wherever possible and appropriate because competition among coordinators promotes cost-based pricing and provides incentives for enhancing customer link management. Accordingly, the Commission directed the Bureau to select one or more database managers pursuant to its existing delegated authority and to consider the benefits of competition during the selection process. On that basis, the Commission determined that there was no reason to set limits on the fees charged by a
database manager.
In March 2004 the Bureau issued a public notice seeking proposals from parties interested in developing and managing the link registration system, and four parties initially submitted proposals. One party decided to remove its proposal from consideration, and the remaining three ultimately submitted an amended joint proposal on September 9, 2004 (Joint Proposal). Later in September 2004, the Bureau designated three companies to be Database Managers for the 70/80/90 GHz bands: Frequency Finder, Inc. (FFI), Micronet Communications, Inc. (Micronet), and Comsearch. In doing so, the Bureau rejected Comsearch’s original proposal to restrict frequency management in the 70/80/90 GHz bands to a single manager. The Bureau also reserved the discretion to designate additional managers or change the current designations at a later date if circumstances indicated that such action was warranted.
The Designation Order acknowledged that the Commission had envisioned a single, shared database if more than one database manager were selected, but the Bureau decided that it could accomplish the same purpose by accepting a joint proposal by the Database Managers to link their separate databases through coordinated communications to form a unified link registration system.
Accordingly, the Bureau required the Database Managers to build a cooperative environment to expedite link registrations through their combined efforts, sharing link information on a continuous basis to provide users, the public and the Commission with access to the most up to-date link information.
Database Managers register links and maintain a record of the requested and approved links for each licensee. In the event of an interference dispute, interference protection rights with regard to affected links are established based on the date and time of link registration, i.e., as between two or more links experiencing or causing interference, the link with the earliest registration date would acquire the right to protection from the later registered link or links, and so on in order of priority based upon the earliest date registered. The Designation Order noted that the Commission had expressly stated that Database Managers would not have authority to recommend specific frequencies to users, but would be responsible for keeping current link registration information to aid in resolution of interference disputes.
In 2005 the Commission revised its rules to (i) require licensees, for each link as part of the registration process, to submit a frequency interference analysis to a Database Manager, and (ii) direct the Database Managers to retain such analyses electronically for subsequent review by the public to aid in the resolution of any interference disputes that might subsequently arise. The Commission foresaw little likelihood that any such disputes would develop after operations commenced in the 70/80/90 GHz bands, but it provided an avenue for interference complaints to be submitted to, and resolved by, the Commission. The Reconsideration Order clarified that the Commission was neither requiring nor precluding Database Managers from providing additional services such as frequency coordination, link design or interference analyses.
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Frequency Bands |
| Band | Use | Service | Table |
| 71 - 76 GHz | 70/80/90 GHz Band | Fixed | N |
| 81 - 86 GHz | 70/80/90 GHz Band | Fixed | N |
| 92 - 95 GHz | 70/80/90 GHz Band | Fixed | N |
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UK Broadband
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According to a UK Broadband press release (c. 2012):
UK Broadband, the UK’s largest holder of 4G spectrum, has today announced that it has switched on its first 4G LTE system in London. This is the first TD-LTE 3.5GHz deployment in the world and the first commercial 4G deployment in the UK. UK Broadband (UKB) is building its network using Huawei’s Time Division Long Term Evolution (TD-LTE) solution.
UKB will operate a wholesale model, working with partners to offer commercial services from May 2012 to businesses, consumers and the public sector. The network will initially cover the Southbank and Borough areas of Southwark.
The network will use UKB’s 124MHz of spectrum in LTE bands 42 and 43 (3.5GHz and 3.6GHz). This allows the deployment of 6 x 20MHz wide channels that will enable UKB to deliver LTE Advanced speeds and enough capacity across the network to deliver Next Generation Access superfast broadband speeds to a large number of users simultaneously.
The first devices, jointly developed by UKB and Huawei, include indoor and outdoor units for high-speed wireless broadband to homes and businesses within the coverage area. Multi-mode mobile devices supporting TD-LTE, FD-LTE and 3G will be available from September 2012.
“We’re very excited to be switching on our first TD-LTE system in the UK using our 4G spectrum,” said Nicholas James, UKB’s CEO. “We’re working with Huawei because we believe they have the expertise and experience we need to deliver the best solution.”
"Utilising Huawei’s equipment, UKB’s spectrum and our combined expertise, the availability of LTE in the UK from today will give a significant boost to the UK’s Government’s broadband agenda,” said Victor Zhang, CEO of Huawei UK. “We are proud to be involved in this project and are dedicated to supporting UKB and the Government to help connect more people to high speed wireless broadband networks.’’
UKB’s business model is to build bespoke LTE coverage – large or small – that delivers solutions to where there is demand for high speed wireless/mobile data capacity. Usually this will be as a result of developing a solution for an anchor or core customer.
UKB has chosen TD LTE because typically, significantly more data is downloaded than uploaded. Designed specifically to meeting the growing demand for data capacity, TD LTE allows UKB to dynamically manage the network to maximise the download capacity at all times, optimising both the technology and the wide spectrum bands it has available to deliver a very high download capacity.
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Frequency Bands |
| Band | Use | Service | Table |
| 3480 - 3500 MHz | UK Broadband TD-LTE | Mobile | - |
| 3580 - 3600 MHz | UK Broadband TD-LTE | Mobile | - |
| 3605 - 3689 MHz | UK Broadband TD-LTE | Mobile | - |
| 3925 - 4009 MHz | UK Broadband TD-LTE | Mobile | - |
External Links:
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Dedicated Short Range Communications (DSRC)
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According to the U.S. Department of Transportation:
DSRC (Dedicated Short Range Communications) is a two-way short- to- medium-range wireless communications capability that permits very high data transmission critical in communications-based active safety applications. In Report and Order FCC-03-324, the Federal Communications Commission (FCC) allocated 75 MHz of spectrum in the 5.9 GHz band for use by Intelligent Transportations Systems (ITS) vehicle safety and mobility applications.
DSRC is a component of the Intelligent Transportation Systems (ITS) radio service.
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Frequency Bands |
| Band | Use | Service | Table |
| 5850 - 5925 MHz | Dedicated Short Range Communications (DSRC) service | Mobile | - |
External Links:
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Skybox high-resolution imaging satellites
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Skybox Imaging plans to launch two non-GSO high-resolution imaging satellites, SkySat-1 and SkySat-2, in 2013. The earth stations and satellites will operate under FCC licenses E130037 and S2862. The uplink and downlink signals use both horizontal and vertical polarization.
According to its website, Skybox Imaging offers a variety of services derived from its imaging data to various industries, including online mapping, oil & gas, financial trading, real estate & construction, natural resources, mining, maritime, forestry, insurance, civil government, humanitarian, telecom & utilities, news & media, location-based services & navigation, and agriculture.
SkySat-1 will operate from an altitude of 578-600 km and orbital period 96.5 min. SkySat-2 will use 637 km and 97.5 min. Both satellites will be in an orbital inclination of about 98 deg.
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Frequency Bands |
| Band | Use | Service | Table |
| 2080.89 - 2081.11 MHz | Skybox Imaging telemetry uplink | Earth Exploration-satellite | N |
| 2082.89 - 2083.11 MHz | Skybox Imaging telemetry uplink | Earth Exploration-satellite | N |
| 8045 - 8105 MHz | Skybox Imaging data downlink | Earth Exploration-satellite | N |
| 8170 - 8230 MHz | Skybox Imaging data downlink | Earth Exploration-satellite | N |
| 8295 - 8355 MHz | Skybox Imaging data downlink | Earth Exploration-satellite | N |
| 8374.744 - 8375.256 MHz | Skybox Imaging telemetry downlink | Earth Exploration-satellite | N |
| 8379.744 - 8380.256 MHz | Skybox Imaging telemetry downlink | Earth Exploration-satellite | N |
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Other 3 billion (03b) Networks
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O3b is a planned satellite system that will help provide broadband service to the world's "other 3 billion" people, generally in the equatorial region, that do not otherwise have good access.
O3b consists of 12 satellites in equatorial medium Earth orbit (MEO) at 8,062 km altitude. The satellites will be able to provide optimal service to +/-45 deg latitude, with limited service to +/-45-62 deg. Therefore, O3b will be able to provide services outside the equatorial regions, including in developed countries, although its main target area is developing countries. MEO was chosen to reduce the latency (round trip travel time) of the data connection, compared to the much larger distance/travel time to geostationary orbit and back.
The satellites will provide broadband service to "Tier 1" customers such as Internet Service Providers (ISPs), and "Tier 2" customers including cellular backhaul and VSAT network services. Because the satellites are not in geostationary orbits, customers will have to use tracking antennas to communicate with the satellites.
Each satellite provides service using ten 216 MHz channels.
O3b will operate in the fixed-satellite service, although FSS allocations do not exist throughout the anticipated frequency range.
O3b is based in Jersey, Channel Islands, and is therefore governed by Ofcom, the U.K. telecommunications regulatory authority. Its network operations center is in Virginia (USA), and its satellite operations center will be in Luxembourg. Multiple ground stations will operate around the globe.
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Frequency Bands |
| Band | Use | Service | Table |
| 17.8 - 18.6 GHz | O3b Networks service and gateway downlinks | Fixed-satellite | N |
| 18.8 - 19.3 GHz | O3b Networks service, gateway, and TT&C downlinks | Fixed-satellite | N |
| 27.6 - 28.4 GHz | O3b Networks service and gateway uplinks | Fixed-satellite | N |
| 28.6 - 29.1 GHz | O3b Networks service, gateway, and TT&C uplinks | Fixed-satellite | N |
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Radio Astronomy Formaldehyde (H2CO) Observations
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Radio astronomers observe molecular lines of formaldehyde at both 14.49 GHz and 4830 MHz. According to the European Science Foundation's Committee on Radio Astronomy Frequencies (CRAF):
At 14.4885 GHz an important formaldehyde (H2CO) line exists, which has been observed in the direction of many galactic sources. Since these lines originate from the upper levels of ortho-formaldehyde their study gives valuable information on the physical conditions of the interstellar medium, because the excitation energies required to produce such lines are different from the energies required to produce the H2CO lines observed at 4829.66 MHz.
There is no formal allocation to the radio astronomy service in these bands, but the international footnote 5.149 and the U.S. footnote US203 note that consideration should be taken to the use of 14.47-14.5 GHz and 4825-4835 MHz band segments for radio astronomy.
In the U.S., there is an increasing use of the entire 14-14.5 GHz band by vehicle-, ship-, and airplane-based Internet terminals that communicate through geostationary satellites (14-14.5 GHz is used as the uplink band). Such activities are required by the FCC to be coordinated with the radio astronomy service.
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Frequency Bands |
| Band | Use | Service | Table |
| 4825 - 4835 MHz | Radio astronomy observations of formaldehyde (4829.66 MHz) | Radio Astronomy | - |
| 14.47 - 14.5 GHz | Radio astronomy observations of formaldehyde (14.4885 GHz) | Radio Astronomy | - |
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AeroMACS
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AeroMACS (Aeronautical Mobile Airport Communications System) is an airport surface wireless broadband communications system based upon the 802.16e (WiMAX) air interface standard. The system is designed to handle air traffic control, airline and airport operations, safety services, and situational awareness at airport facilities.
AeroMACS will be deployed in protected aeronautical mobile (route) service spectrum (5091-5150 MHz) for airport surface applications that involve safety and regularity of flight, according to the U.S. Federal Aviation Administration. It is designed to allow international interoperability.
The expected timeline for AeroMACS includes initial deployments from 2013-2016, and full deployment in 2022 and beyond.
According to the FAA Engineering Brief 97 Draft, dated Feb 1, 2016:
Background
Current ground-to-ground communication at the airport surface uses the aeronautical frequencies (Very High Frequencies (VHF) in the 117.975-137MHz band). However, the aeronautical band is very congested. Moreover, the aeronautical band was designed for the analog voice communication and may not be suitable to introduce Federal Aviation Administration (FAA) NextGen technologies. The International Telecommunication Union (ITU) and International Civil Aviation Organization (ICAO) organizations developed the AeroMACS system to address ground-to-ground communication congestion issues and to provide a platform to support the future introduction of NextGen technologies. The FAA, EUROCONTROL, ICAO, Radio Technical Commission for Aeronautics (RTCA) and European Organization for Civil Aviation Equipment (EUROCAE) are currently working to develop standards for AeroMACS.
AeroMACS is a broadband wireless service operating in a protected aeronautical frequency band for use on the airport surface. In the near future, the FAA, airlines, and airport authorities will be using AeroMACS for some ground-to-ground communication purposes. Broadband wireless communication systems like AeroMACS will also open up opportunities to introduce new technology services for both the airport and aircraft. This wireless communication link will enable the airports to improve their operational efficiency and is less costly to install/maintain than traditional infrastructure.
AeroMACS History
a. The 2007 World Radiocommunications Conference (WRC-07) approved the allocation of the 5091-5150 MHz band to the Aeronautical Mobile (Route) Service [AM(R)S], enabling aeronautical safety communication on the airport surface.
b. Based on the WRC-07 decision, ICAO developed the standards and recommended practices (SARPS) for AeroMACS as a broadband wireless communication service operating in a protected aeronautical communications frequency band to allow ground operation safety and air traffic management (ATM)/regularity of flight on the airport surface functions. The protected broadband wireless service may be used by Air Navigation Service Providers, e.g. the Federal Aviation Administration (FAA), as well as airlines and airport operators.
c. The Federal use of AeroMACS and its associated frequencies is approved by the National Telecommunications and Information Administration (NTIA). Based on the approval, FAA/NASA performed Federal AeroMACS field trials at the Cleveland-Hopkins International Airport (CLE). The FAA Airport Surface Surveillance Capability (ASSC) program office will be using AeroMACS at different airports through the US.
d. Currently, the Federal Communications Commission (FCC) is in the process of approving the nonfederal use of AeroMACS by airport operators through the rulemaking process.
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Frequency Bands |
| Band | Use | Service | Table |
| 5091 - 5150 MHz | AeroMACS | ARMR | - |
External Links:
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Foreign Object Debris (FOD) detection radars
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According to the FCC, "Foreign Object Debris (FOD) at airports, including any substance, debris, or object in a location that can damage aircraft or equipment, can seriously threaten the safety of airport personnel and airline passengers and can have a negative impact on airport logistics and operations." (FCC 11-185).
The FCC has granted a waiver to Trex Enterprises Corporation to build FOD detection radars, and for the radars to be operated at airports under Part 90 of the FCC rules. The Trex devices are limited to 100 mW transmit power, 45 dBi gain antennas, 35 dBW total EIRP, vertical polarization, 3 dB beamwidth of 1 deg (elevation) by 0.4 deg (az), and FMCW (elevation scan) chirp rate of 139.5 Hz.
Through the same document (FCC 11-185), the FCC proposes broader flexibility to operate FOD detection radars, and other radars, in the 78-81 GHz band on an unlicensed basis under Part 15.
According to the Trex Enterprises' Web site, full surface coverage "FOD Finder" detection vehicles are already operating at Chicago O'Hare, Honolulu, and San Diego airports, and Elmendorf, Hill, and Holloman Air Force bases.
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Frequency Bands |
| Band | Use | Service | Table |
| 78 - 81 GHz | Foreign Object Debris (FOD) detection radars | Radiolocation | - |
External Links:
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