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U.S., French export-credit agencies' role in OneWeb remains ...
src: spacenews.com

The OneWeb satellite constellation--formerly known as WorldVu--is a proposed constellation of approximately 648 satellites expected to provide global Internet broadband service to individual consumers as early as 2019. The constellation is proposed by the company WorldVu Satellites Ltd., which has used the alternate name L5 in various regulatory filings. OneWeb is registered in St. Helier, Jersey and is expected to require up to US$3 billion in capital by the time the full constellation becomes operational in 2019-2020.

The 648 communication satellites will operate in circular low Earth orbit, at approximately 750 miles (1,200 km) altitude, transmitting and receiving in the Ku band of the radio frequency spectrum. Most of the capacity of the initial 648 satellites has been sold, and OneWeb is considering nearly quadrupling the size of the satellite constellation by adding 1,972 additional satellites that it has priority rights to.

The company's business plan is to attempt to "reach hundreds of millions of potential users residing in places without [existing] broadband access."


Video OneWeb satellite constellation



History

Early reports of the potential involvement of Google in offering broadband internet services surfaced in February 2014, when a "very large [satellite] constellation" was rumored to be as large as 1600 satellites.

By June 2014, WorldVu (which would later be renamed OneWeb) had acquired the satellite spectrum that was formerly owned by SkyBridge, a company that went bankrupt in 2000 in an attempt to offer broadband Internet services via satellite.

As of September 2014, the WorldVu company had 30 employees. In September 2014, several Google employees who had joined Google as part of the acquisition of O3b Networks in 2013--Greg Wyler, Brian Holz and David Bettinger--left Google to become a part of WorldVu Satellites Ltd. The rights to the radio frequency spectrum were transferred to WorldVu. As of August 2014, it was unclear why the WorldVu team left Google, as well as what Google's role might be in WorldVu going forward. At the time, WorldVu was working closely with SpaceX and SpaceX' founder Elon Musk, although no formal relationship had been established and no launch commitments had been made.

In May 2014, the plan was to have at least 20 satellites operating in each of 20 different orbital planes to provide consistent coverage over the surface of the Earth.

By November 2014, the Wall Street Journal was reporting that Musk and Wyler were considering options for building a factory to manufacture high-volume low-cost satellites, and that "initial talks have been held with state officials in Florida and Colorado" about potentially locating a factory in those states, as well as that SpaceX would likely launch the satellites. Also in November, WorldVu issued a tender "to satellite manufacturers for 640 125-kilogram satellites", asking for responses by mid-December, having secured regulatory approval for use of the requisite electromagnetic spectrum communication frequencies in mid-2014.

The 2014 OneWeb solicitation to satellite manufacturers was for a total build of approximately 900 small Internet-delivery satellites, including ground and on-orbit spares. Responses were received from both European and US manufacturers including Airbus Defence and Space, Lockheed Martin Space Systems, OHB SE, SSL and Thales Alenia Space, and discussions have focused on how each of these companies "are going to escape their status-quo histories as major space hardware contractors and remake themselves into producers capable of producing multiple satellites per month, each with a cost of less than US$500,000." OneWeb announced that it plans to form a joint venture with the winning bidder and open a new facility for manufacturing the new smallsats.

In January 2015, the Wall Street Journal reported that WorldVu, now operating under the name OneWeb LTD, had secured funding from Virgin Group and Qualcomm to build and launch the constellation, while SpaceX was not an investor and their role in the venture was not clear. OneWeb also divulged that the planned satellites will weigh approximately 125 kg (276 lb) and that plans are to deploy approximately 650 of them in low Earth orbit to operate at 1,200 kilometers (750 mi) altitude. A few days later, Elon Musk announced the rival SpaceX satellite constellation venture, with the opening of the SpaceX satellite development facility in Seattle, with the intent of taking SpaceX itself into the business of internet provision and internet backhaul services, aiming to build an approximately 4000 satellite constellation, with the first generation becoming operational in approximately 2020.

The satellites for the OneWeb constellation were initially announced to be in the 110 kilograms (250 lb)-class, about the same size as the 2 Earth-imaging satellites that are operated by Skybox Imaging, which Google acquired in August 2014. However, by the following year, sources put the satellites nearer 175-200 kg (386-441 lb) in mass.

In March 2015, OneWeb indicated that they intended to select a launch service provider by mid-2015 and in June 2015 announced that Arianespace is contracted to provide 21 multi-sat launches on Soyuz beginning in 2017 with Virgin Galactic under contract to provide 39 single-sat launches using its LauncherOne smallsat launch vehicle. There is also an option to use Ariane 6 for up to three launches after 2021, making this the first contract announced for the Ariane launch vehicle.

By June 2015, the company modified their plan somewhat to orbit a total constellation of 720 satellites, operating in low Earth orbit at 1,200 kilometres (750 mi) altitude, which plan was somewhat reduced by early 2016 with only 640 satellites planned, but still at 1200 km.

In June 2015, it was announced that Airbus Defence and Space was selected to build the satellites. One year on, in June 2016, development was on schedule with the first ten satellites still headed for a 2017 launch on a Europeanized Soyuz launch vehicle.

In December 2016, SoftBank Group Corp agreed to invest $1 billion in OneWeb. Softbank will become OneWeb's largest shareholder, with a roughly 40% stake. Another $200 million will be funded by its current investors, which include Qualcomm Inc, Airbus Group and Virgin Group. The transaction was expected to close in the first quarter of 2017.

In February 2017, OneWeb announced that it had sold most of the capacity of its initial 648 satellites, and was considering nearly quadrupling the size of the satellite constellation by adding 1,972 additional satellites that it has priority rights to. With the original capital raise of $500 million in 2015, plus the $1 billion investment of SoftBank in 2016, previous "investors committed to an additional $200 million, bringing OneWeb's total capital raised to $1.7 billion."

In March 2017, OneWeb filed with the US regulatory authorities plans to field a constellation of an additional 2000 "V-band satellites in non-geosynchronous orbits to provide communications services" in an electromagnetic spectrum that had not been previously been "heavily employed for commercial communications services." This would include "720 LEO V-band satellites at 1,200 kilometers, and another constellation in Medium Earth Orbit (MEO) of 1,280 satellites."

Some controversy has arisen in 2015-2017 with regulatory authorities on licensing the communications spectrum for these large constellations of satellites. The traditional and historical regulatory rule for satellites licensing comm spectrum has been that satellite operators could "launch a single spacecraft to meet their in-service deadline [from the regulator], a policy seen as allowing an operator to block the use valuable radio spectrum for years without deploying its fleet." The US regulatory authority has set a six-year deadline to have an entire large constellation deployed to comply with licensing terms. The international regulator, the ITU, has proposed by mid-2017 an international guideline that would be considerably less restrictive. As of September 2017, both Boeing and SpaceX have petitioned the US FCC for a waiver of the 6-year rule, while OneWeb has received FCC approval under the existing regime.


Maps OneWeb satellite constellation



Design characteristics

The satellites for the OneWeb constellation are reportedly 175-200 kg (386-441 lb) in mass. The 648 operational satellites will operate in 18 polar orbit planes at 1,200 kilometres (750 mi) altitude.

The satellites will operate in the Ku band, communicating in the microwave range of frequencies in the 12-18 GHz portion of the electromagnetic spectrum. Each satellite will provide aggregate downlink capacity of 17 to 23 gigabits per second. The satellites use a technique called "progressive pitch" in which the satellites are slightly turned to avoid interference with Ku-band satellites in geostationary orbit. The user terminal antenna on the ground will be a phased array antenna measuring approximately 36 by 16 centimeters (14.2 by 6.3 in) and will provide Internet access at 50 megabits/second.

The satellites will be designed to comply with "orbital debris-mitigation guidelines for removing satellites from orbit and, for low-orbit satellites, assuring that they reenter the Earth's atmosphere within 25 years of retirement."


OneWeb Constellation - YouTube
src: i.ytimg.com


Manufacturing and constellation rollout

The initial operational constellation was originally (June 2014) planned to be just half of the total of 720 satellites. A quarter of the satellites will make up the initial constellation, and these would operate in the lower of the two proposed orbits, at approximately 850 kilometres (530 mi). The initial constellation would presumably be raised or lowered into its final orbital altitude of either 800 kilometres (500 mi) or 950 kilometres (590 mi) as consumer and business use of the broadband service grows over time. By early 2015, OneWeb indicated that the first launches will occur no earlier than 2017.

In February 2016, OneWeb announced that they would set up an assembly and test facility in Florida. They plan to assemble and launch more than 648 satellites by the end of 2019, but will manufacture an additional 250 of the 140-kilogram-satellites (300 lb) as spares to be used in later years.


One year after kickoff, OneWeb says its 700-satellite ...
src: spacenews.com


Concerns

End-of-life concerns

With such a large number of satellites being added to the already crowded low Earth orbit, plans for handling the satellites once the operational life of each satellite is completed are an important consideration. The region between 600 and 1,000 kilometres (370 and 620 mi) is already the most congested orbital regime around Earth, and concerns about adding to the existing space debris problem have been expressed. There could be a new regime of graveyard orbits added, similar to those in use for decades to handle post-operational commsats that operated in the geostationary belt; however at the orbital altitudes envisioned for WorldVu, the disposal orbit may not have a sufficiently long life to assure long-term stability.

An alternative that has been proposed for years is to introduce the capability to retrieve derelict objects for near-space clean up and then either deorbit the satellite or do some sort of in-space recycling of the satellite materials. Several technical approaches have been proposed, but there has been no legal framework to date that has required satellite operators to clean up the negative externality of their derelict satellites. New approaches offer the technical prospect of markedly reducing the cost of object capture and deorbit with the implementation of a one-up/one-down launch license regime to Earth orbits that would require satellite operators to remove one spacecraft for each one deployed.

By October 2017, OneWeb had filed documents with the US FCC with their space debris mitigation plan. OneWeb "satellites are designed for mission lives of at least five years, and 'the post-mission disposal operation is anticipated to take less than one year.' OneWeb also said it has designed its satellite network to avoid collisions with space stations and debris, and that OneWeb 'will actively and regularly screen for conjunctions between its own satellites and other objects in the Joint Space Operations Center's ('JSpOC') published catalog."

Interference with other Earth-bound transceivers

OneWeb competitor, satellite fleet operator ABS, has expressed concerns about the amount of electromagnetic interference that the OneWeb constellation could add to existing terrestrial transceivers.


Creating the world's largest ever satellite constellation | Virgin
src: res.cloudinary.com


Competition

Competition to OneWeb for producing smaller and lower-cost satellites in general is thought to come "from other makers of small satellites, such as Nevada-based Sierra Nevada Corp. and Britain's Surrey Satellite Technology Ltd." In broadband internet service provision more specifically, there are a large number of alternatives to the proposed WorldVu satellite broadband service, mostly involving wired and terrestrial radio broadband service.

Other potential competitors in the satellite internet space are the SpaceX satellite constellation and a 2015 proposal from Samsung outlining a 4600-satellite constellation orbiting at 1,400 kilometers (900 mi) that could bring 200 gigabytes per month of internet data to "each of the world's 5 billion people".

One advantage OneWeb was perceived to have was that, as of January 2015, no other competitor had obtained a license from the International Telecommunication Union to operate a Ku-band satellite network that is not placed in a geosynchronous orbit.

Historically, earlier companies that have attempted to build satellite internet service networks and provide space-based internet connections have not fared well, as both services were hobbled by high costs which consequently attracted few users. Iridium SSC filed for bankruptcy protection in 1999 and Globalstar did the same in 2002.


Inter-Satellite Connectivity Opportunities for OneWeb ...
src: i.ytimg.com


See also

  • Iridium satellite constellation - an operational constellation of 66 active satellites used to provide global satellite phone service
  • ORBCOMM - an operational constellation used to provide global asset monitoring and messaging services from its constellation of 29 LEO communications satellites orbiting at 775 km
  • Teledesic - a former (1990s) venture to accomplish broadband satellite internet services
  • Kymeta - small form factor satellite antennas for mobile terrestrial applications

Google, Facebook, SpaceX want Internet via air, space - CNN
src: cdn.cnn.com


References


OneWeb LEO Airbus Satellite HD 720p H264 - YouTube
src: i.ytimg.com


External links

  • The New Space Race: One Man's Mission to Build a Galactic Internet, Bloomberg Businessweek, 22 January 2015.
  • In Conversation with OneWeb Founder Greg Wyler, SpaceNews, 20 November 2015.
  • Internet for Everyone, Everywhere - CNN, CNN, 30 October 2015.

Source of the article : Wikipedia

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