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49-446: (Redirected from C-band ) C band may refer to: C band (IEEE) , a radio frequency band from 4 to 8 GHz C band (infrared) , an infrared band from 1530 to 1565 nm (roughly 200 THz) C band (NATO) , a radio frequency band from 500 MHz to 1 GHz C-banding , in genetics Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

98-483: A "polarotor" setup). Higher-end receivers did this transparently, switching polarization and moving the dish automatically as the user changed channels. By Spring of 1984, 18 C-Band satellites were in use for United States domestic communications, owned by five different companies. (degrees longitude) The retail price for satellite receivers soon dropped, with some dishes costing as little as $ 2,000 by mid-1984. Dishes pointing to one satellite were even cheaper. Once

147-549: A case of "unauthorized reception" by TVRO consumers; and to what extent it was legal for a service provider to encrypt their signals in an effort to prevent its reception. The Cable Communications Policy Act of 1984 clarified all of these matters, making the following legal: This created a framework for the wide deployment of encryption on analog satellite signals. It further created a framework (and implicit mandate to provide) subscription services to TVRO consumers to allow legal decryption of those signals. HBO and Cinemax became

196-540: A consequence of the higher frequency used for DBS services is rain fade where viewers lose signal during a heavy downpour. C-band's immunity to rain fade is one of the major reasons the system is still used as the preferred method for television broadcasters to distribute their signal. TVRO systems were most popular in rural areas, beyond the broadcast range of most local television stations . The mountainous terrain of West Virginia , for example, makes reception of over-the-air television broadcasts (especially in

245-735: A high band K u LNBF using circular polarization . Older mesh dishes with perforations larger than 5mm are inefficient at K u frequencies, because the smaller wavelengths will pass through them. Solid fiberglass dishes usually contain metal mesh with large-diameter perforations as a reflector and are usually unsuitable for anything other than C band. Large dishes have higher antenna gain , which can be an advantage when used with DBS signals such as Dish Network and DirecTV , virtually eliminating rain fade. Restored dishes fitted with block upconverters can be used to transmit signals as well. BUDs can still be seen at antenna farms for these reasons, so that video and backhauls can be sent to and from

294-422: A lower noise temperature to receive digital broadcasts. With a suitable replacement LNB (provided there is no warping of the reflector) a BUD can be used to receive free-to-air (FTA) and DBS signals. Several companies market LNBs, LNBFs, and adaptor collars for big-dish systems. For receiving FTA signals the replacement should be capable of dual C/K u reception with linear polarization , for DBS it will need

343-454: A price ($ 12.95 per month) higher than what cable subscribers were paying. This sentiment, and a collapse in the sales of TVRO equipment in early 1986, led to the April 1986 attack on HBO's transponder on Galaxy 1 . Dish sales went down from 600,000 in 1985 to 350,000 in 1986, but pay television services were seeing dishes as something positive since some people would never have cable service, and

392-473: A user paid for a dish, it was possible to receive even premium movie channels, raw feeds of news broadcasts or television stations from other areas. People in areas without local broadcast stations, and people in areas without cable television, could obtain good-quality reception with no monthly fees. Two open questions existed about this practice: whether the Communications Act of 1934 applied as

441-754: Is a term used chiefly in North America , South America to refer to the reception of satellite television from FSS -type satellites, generally on C-band analog; free-to-air and unconnected to a commercial DBS provider. TVRO was the main means of consumer satellite reception in the United States and Canada until the mid-1990s with the arrival of direct-broadcast satellite television services such as PrimeStar , USSB , Bell Satellite TV , DirecTV , Dish Network , Sky TV that transmit K u signals. While these services are at least theoretically based on open standards ( DVB-S , MPEG-2 , MPEG-4 ),

490-476: Is reserved exclusively for radar altimeter installed on board aircraft and for the associated transponders on the ground. In February 2020, the U.S. Federal Communications Commission adopted rules for the C ;band at 3.7–4.2 GHz that allocated the lower 280 megahertz of the band, at 3.7–3.98 GHz, for terrestrial wireless use. Existing satellite operators will have to repack their operations into

539-632: Is still common in Europe and India , although the TVRO nomenclature was never used there. Free-to-air satellite signals are also very common in the People's Republic of China , as many rural locations cannot receive cable television and solely rely on satellites to deliver television signals to individual homes. The term "BUD" (big ugly dish) is a colloquialism for C-Band satellite dishes used by TVRO systems. BUDs range from 4 to 16 feet in diameter, with

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588-533: The Space Shuttle program. Only seven K u band satellites were in use. In addition to encryption, DBS services such as PrimeStar had been reducing the popularity for TVRO systems since the early 1990s. Signals from DBS satellites (operating in the more recent K u band) are higher in both frequency and power (due to improvements in the solar panels and energy efficiency of modern satellites) and therefore require much smaller dishes than C-band, and

637-451: The digital signals now used require far less signal strength at the receiver, resulting in a lower cost of entry . Each satellite also can carry up to 32 transponders in the K u band, but only 24 in the C band, and several digital subchannels can be multiplexed (MCPC) or carried separately ( SCPC ) on a single transponder. General advances, such as HEMT , in noise reduction at microwave frequencies have also had an effect. However,

686-680: The television network with which a station is affiliated , without interruption due to inclement weather . BUDs are also still useful for picking-up weak signals at the edge of a satellite's broadcast "footprint" – the area at which a particular satellite is aimed. For this reason, BUDs are helpful in places like Alaska , or parts of the Caribbean . Large parabolic antennas similar to BUDs are still in production. New dishes differ in their construction and materials. New mesh dishes have much smaller perforations and solid dishes are now made with steel instead of fiberglass. New systems usually include

735-407: The 5.725 - 5.875 GHz ISM band allowing unlicensed use by low power devices, such as garage door openers , wireless doorbells , and baby monitors . A very large use is by the high frequency (5.2 GHz) band of Wi-Fi ( IEEE 802.11a ) wireless computer networks. These are the most widely used computer networks in the world, used to allow laptops , smartphones , printers and TVs to connect to

784-407: The 5.8 GHz ISM band between 5.725 and 5.875 GHz, which is used for medical and industrial heating applications and many unlicensed short-range microwave communication systems, such as cordless phones , baby monitors , and keyless entry systems for vehicles. The C-band frequencies of 5.4 GHz band [5.15 to 5.35 GHz, 5.47 to 5.725 GHz, or 5.725 to 5.875 GHz, depending on

833-421: The C band is highly associated with television receive-only satellite reception systems, commonly called "big dish" systems, since small receiving antennas are not optimal for C band. Typical antenna sizes on C-band-capable systems range from 6 to 12 feet (1.8 to 3.5 meters) on consumer satellite dishes, although larger ones also can be used. For satellite communications, the microwave frequencies of

882-430: The C band perform better under adverse weather conditions in comparison with the K u  band (11.2–14.5  GHz ), microwave frequencies used by other communication satellites . Rain fade  – the collective name for the negative effects of adverse weather conditions on transmission – is mostly a consequence of precipitation and moisture in the air . The C band also includes

931-643: The C-Band Alliance (CBA) was established in September 2018 by the four satellite operators— Intelsat , SES , Eutelsat and Telesat —that provide the majority of C-band satellite services in the US, including media distribution reaching 100 million US households. The consortium made a proposal to the FCC to act as a facilitator for the clearing and repurposing of a 200 MHz portion of C-band spectrum to accelerate

980-514: The C-Band Alliance was dead. Among other claims, Intelsat argued that it was obvious that the FCC was already treating each satellite operator individually and that it therefore made business sense for each company to respond to the FCC from its own commercial perspective. One of the major members of the C-Band Alliance, Intelsat, filed for bankruptcy on 14 May 2020, just before the new 5G spectrum auctions were to take place, with over US$ 15 billion in total debt. Public information showed that

1029-1104: The auction. In December 2021, Boeing and Airbus called on the US government to delay the rollout of new 5G phone service that uses C band due to concern of the interference with some sensitive aircraft instruments, especially radio altimeters operating at 4.2–4.4 GHz. On January 18, 2022, Verizon and AT&T announced that they would delay their C-band 5G rollout near airports in response to those concerns. 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 Television receive-only Television receive-only ( TVRO )

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1078-599: The band of frequencies from 5.925 to 6.425 GHz for their uplinks . Note that by using the band from 3.7  to 4.0 GHz, this C band overlaps somewhat with the IEEE S band for radars. The C-band communication satellites typically have 24 radio transponders spaced 20 MHz apart, but with the adjacent transponders on opposite polarizations such that transponders on the same polarization are always 40 MHz apart. Of this 40 MHz, each transponder utilizes about 36 MHz. The unused 4.0 MHz between

1127-459: The company had been considering bankruptcy protection from at least as early as February 2020. Slight variations in the assignments of C-band frequencies have been approved for use in various parts of the world, depending on their locations in the three ITU radio regions. Note that one region includes all of Europe and Africa , plus all of Russia ; a second includes all of the Americas, and

1176-486: The deployment of next generation 5G services, while protecting incumbent users and their content distribution and data networks in the US from potential interference. The C-Band Alliance lobbied for a private sale, but the FCC and some members of Congress wanted an auction . In November 2019, the FCC announced that an auction was planned, which took place in December 2020. Cable operators wanted to be compensated for

1225-427: The dishes used for satellite TV reception were 12 to 16 feet in diameter and made of solid fiberglass with an embedded metal coating, with later models being 4 to 10 feet and made of wire mesh and solid steel or aluminum . Early dishes cost more than $ 5,000, and sometimes as much as $ 10,000. The wider the dish was, the better its ability to provide adequate channel reception. Programming sent from ground stations

1274-409: The first two services to announce intent to encrypt their satellite feeds late in 1984. Others were strongly considering doing so as well. Where cable providers could compete with TVRO subscription options, it was thought this would provide sufficient incentive for competition. HBO and Cinemax began encrypting their west coast feeds services with VideoCipher II 12 hours a day early in 1985, then did

1323-481: The higher UHF frequencies) very difficult. From the late 1970s to the early 1990s DBS systems were not available, and cable television systems of the time only carried a few channels, resulting in a boom in sales of systems in the area, which led to the systems being termed the "West Virginia state flower". The term was regional, known mostly to those living in West Virginia and surrounding areas. Another reason

1372-474: The industry was starting to recover as a result. Through 1986, other channels that began full time encryption included Showtime and The Movie Channel on May 27, and CNN and CNN Headline News on July 1. Scrambling would also lead to the development of pay-per-view , as demonstrated by the early adoption of encryption by Request Television , and Viewer's Choice . Channels scrambled (encrypted) with VideoCipher and VideoCipher II could be defeated, and there

1421-477: The internet through a wireless router in home and small office networks, and access points in hotels, libraries, and coffee shops. The communications C band was the first frequency band that was allocated for commercial telecommunications via satellites. The same frequencies were already in use for terrestrial microwave radio relay chains. Nearly all C-band communication satellites use the band of frequencies from 3.7  to 4.2 GHz for their downlinks , and

1470-461: The loss of 200 MHz, which would not include a guard band of 20 MHz to prevent interference. By late 2019, the commercial alliance had weakened. Eutelsat formally pulled out of the consortium in September 2019 over internal disagreements. By February 2020, it became even less of a factor in C-band spectrum reallocation as Intelsat pulled out of the alliance and communicated to the FCC that

1519-444: The majority of services are encrypted and require proprietary decoder hardware. TVRO systems relied on feeds being transmitted unencrypted and using open standards, which heavily contrasts to DBS systems in the region. The term is also used to refer to receiving digital television " backhaul " feeds from FSS-type satellites. Reception of free-to-air satellite signals, generally K u band Digital Video Broadcasting , for home viewing

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1568-444: The most popular large size being 10 feet. The name comes from their perception as an eyesore . TVRO systems were originally marketed in the late 1970s. On October 18, 1979, the FCC began allowing people to have home satellite earth stations without a federal government license. The dishes were nearly 20 feet (6.1 m) in diameter, were remote controlled, and could only pick up HBO signals from one of two satellites. Originally,

1617-665: The number of systems in existence, their lack of usefulness, and because many people consider them an eyesore, used BUDs can be purchased for very little money. As of 2009, there are 23 C-band satellites and 38 K u /K a band satellites. There were over 150 channels for people who want to receive subscription channels on a C-band dish via Motorola's 4DTV equipment via two vendors Satellite Receivers Ltd (SRL) and Skyvision . The 4DTV subscription system shutdown on August 16, 2016. The dishes themselves can be modified to receive free-to-air and DBS signals. The stock LNBs fitted to typical BUDs will usually need to be replaced with one of

1666-552: The pairs of transponders act as guard bands for the likely case of imperfections in the microwave electronics . One use of the C band is for satellite communication, whether for full-time satellite television networks or raw satellite feeds, although subscription programming also exists. This use contrasts with direct-broadcast satellite , which is a completely closed system used to deliver subscription programming to small satellite dishes that are connected with proprietary receiving equipment. The satellite communications portion of

1715-446: The ranges 5.830 to 5.850 GHz for down-links and 5.650 to 5.670 GHz for up-links. This is known as the 5-centimeter band by amateurs and the C band by AMSAT . Particle accelerators may be powered by C-band RF sources. The frequencies are then standardized at 5.996 GHz (Europe) or 5.712 GHz (US), which is the second harmonic of S band . Several tokamak fusion reactors use high-power C-band RF sources to sustain

1764-541: The region of the world] are used for Wi-Fi wireless computer networks in the 5 GHz spectrum . The C-Band Alliance was an industry consortium of four large communications satellite operators in 2018–2020. In response to a Notice of Proposed Rulemaking of July 2018 from the US Federal Communications Commission (FCC) to make the 3.7 to 4.2 GHz spectrum available for next-generation terrestrial fixed and mobile broadband services,

1813-524: The same with their east coast feeds by August. The two networks began scrambling full time on January 15, 1986, which in many contemporary news reports was called "S-Day". This met with much protest from owners of big-dish systems, most of which had no other option at the time for receiving such channels. As required by the Cable Communications Policy act of 1984, HBO allowed dish owners to subscribe directly to their service, although at

1862-428: The satellite, and each satellite had a fixed number of transponders, dishes were usually equipped with a modified polar mount and actuator to sweep the dish across the horizon to receive channels from multiple satellites. Switching between horizontal and vertical polarization was accomplished by a small electric servo motor that moved a probe inside the feedhorn throat at the command of the receiver (commonly called

1911-481: The ship rather than its own gyros, improving accuracy and reducing maintenance. As of 2010, SeaTel continues to dominate the market for stabilized TVRO systems and has according to the Comsys group, a market share of 75%. Other established providers of stabilised satellite antennas are Intellian, KNS, Orbit, EPAK and KVH. Most of the free analogue channels that BUDs were built to receive have been taken offline. Due to

1960-512: The third region includes all of Asia outside of Russia, plus Australia and New Zealand . This latter region is the most populous one, since it includes China , India , Pakistan , Japan , and Southeast Asia . The Radio Regulations of the International Telecommunication Union allow amateur radio operations in the frequency range 5.650 to 5.925 GHz, and amateur satellite operations are allowed in

2009-464: The title C band . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=C_band&oldid=1066456576 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages C band (IEEE) The C band contains

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2058-446: The toroidal plasma current. Common frequencies include 3.7 GHz ( Joint European Torus , WEST (formerly Tore Supra) ), 4.6 GHz (Alcator C, Alcator C-Mod , EAST , DIII-D ), 5 GHz ( KSTAR , ITER ) and 8 GHz ( Frascati Tokamak Upgrade ). The band 4.2–4.4 GHz is currently allocated to the aeronautical radionavigation service (ARNS) on a primary worldwide basis. RR No. 5.438 notes specifically that this band

2107-584: The two million satellite dish users in the United States still used C-band. ABC and CBS were considering scrambling, though CBS was reluctant due to the number of people unable to receive local network affiliates . The growth of dishes receiving K u band signals in North America was limited by the Challenger disaster , since 75 satellites were to be launched prior to the suspension of

2156-402: The upper 200 megahertz of the band, from 4.0 to 4.2 GHz, and there is a 20-megahertz guard band at 3.98–4.0 GHz. Licenses to use the 3.7–3.98 GHz band were auctioned in December 2020. Verizon, AT&T and T-Mobile are main winners of the auction . Verizon, AT&T, and T-Mobile spent approximately $ 45 billion, $ 23 billion, and $ 9 billion respectively during

2205-524: Was a black market for illegal descramblers. By the end of 1987, 16 channels had employed encryption with another 7 planned in the first half of 1988. Packages that offered reduced rates for channels in bulk had begun to appear. At this time, the vast majority of analog satellite TV transponders still were not encrypted. On November 1, 1988, NBC began scrambling its C-band signal but left its K u band signal unencrypted in order for affiliates to not lose viewers who could not see their advertising. Most of

2254-557: Was introduced around 1994. Many long-disconnected dishes still occupy their original spots. The term TVRO has been in use on ships since it was introduced in the 1980s. One early provider of equipment was SeaTel with its first generation of stabilized satellite antennas that was launched in 1985, the TV-at-Sea 8885 system. Until this time ships had not been able to receive television signals from satellites due to their rocking motion rendering reception impossible. The SeaTel antenna however

2303-552: Was relayed from 18 satellites in geostationary orbit located 22,300 miles above the Earth. The dish had to be pointed directly at the satellite, with nothing blocking the signal. Weaker signals required larger dishes. The dishes worked by receiving a low-power C-Band (3.7–4.2 GHz) frequency-modulated analog signal directly from the original distribution satellite – the same signal received by cable television headends . Because analog channels took up an entire transponder on

2352-418: Was stabilized using electrically driven gyroscopes and thus made it possible to point to the satellite accurately enough, that is to within 2°, in order to receive a signal. The successful implementation of stabilised TVRO systems on ships immediately led to the development of maritime VSAT systems. The second generation of SeaTel TVRO systems came in 1994 and was the 2494 antenna, which got its gyro signal from

2401-526: Was the large sizes of the dishes. The first satellite systems consisted of "BUDs" twelve to sixteen feet in diameter. They became much more popular in the mid-1980s when dish sizes decreased to about six to ten feet, but have always been a source of much consternation (even local zoning disputes) due to their perception as an eyesore . Neighborhoods with restrictive covenants usually still prohibit this size of dish, except where such restrictions are illegal. Support for systems dried up when strong encryption

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