ngso constellation

ngso constellation插图

Non-geostationary orbit
Non-geostationary orbit(NGSO) satellite constellations represent a cornerstone in the NewSpace paradigm and thus have become one of the hottest topics for the industry,academia,but also for national space agencies and regulators.Cite As:arXiv:2203.16597 [cs.NI]DOI:10.48550/arXiv.2203.16597Published:2022/03/30Subject:Networking and Internet Architecture (cs.NI)

What does NGSO stand for?

Some players have therefore proposed in the past or more recently the deployment of constellations of satellites in non-geostationary orbit (NGSO) i.e. in low Earth orbit at between 500 and 2000 km altitude and in medium Earth orbit at between 6000 and 20 000 km altitude.

How do non-GSO satellites work?

Since non-GSO satellites move across the sky during their orbit around the Earth, non-GSO operators must deploy a fleet of satellites, generally called “constellations, to provide continuous service from these altitudes.

Do NGSO system operations interfere with GSO operations?

The record reflects widespread recognition of the need to ensure that NGSO system operations do not adversely impact GSO operations. The uplink equivalent power-flux density (“EPFD”) limits proposed in the NPRM would not adequately protect GSO networks from interference generated by the NGSO systems proposed in the pending processing rounds.

How many satellites are needed to deploy a constellation?

On the other hand, the deployment of such a constellation requires use of several tens of satellites (e.g. in the O3bNetworks, Globalstar or Iridium, Skybridge satellite networks) to several hundred satellites (e.g. Teledesic or WorldVu) in order to guarantee continuity of service in the inhabited areas of the terrestrial globe.

What frequencies are used in FSS?

There is a need to encourage the development and implementation of new technologies in the FSS at frequencies above 30 GHz. The FSS systems based on the use of new technologies above 30 GHz and associated with both GSO and non-GSO satellite constellations can provide high-capacity and low-cost means of communication even to the most isolated regions of the world.

How high are satellites above the Earth?

Geostationary (GSO) satellites are at 36 000 kilometres above the Earth, a place where they appear fixed in the sky when observed from the ground. Non-GSO satellites at medium Earth orbits (MEO) altitudes are between 8 000 and 20 000 kilometres above the Earth and low E?arth orbits (LEO) altitudes are between 400 to 2 ?000 kilometres above …

What is the ITU radio regulation?

The ITU Radio Regulations (RR) enable the introduction of new applications of radiocommunication technology while ensuring the efficient use of radio-frequency spectrum, i.e. the operation of as many systems as possible, without interference.

What is non-geostationary satellite?

The rapidly increasing use of non-geostationary satellite orbits (non-GSO), such as medium Earth orbits (MEO) and low Earth orbits (LEO), represents an important innovation in satellite technology – and a potential breakthrough in connecting the unconnected so that they, too, can reap the benefits of today’s digital economy.

Why are satellites important?

Satellite systems offer significant advantages for expanding broadband coverage: they provide instant-on coverage across wide geographies without regard to challenging topography; they are reliable and largely immune to many risks that other networks face, including accidental damage, theft, conflict areas and natural disasters.

What is a milestone based approach?

The milestone-based approach will provide a regulatory mechanism to help ensure that the Master International Frequency Register (MIFR) reasonably reflects the actual deployment of such non-GSO satellite systems in specific radio-frequency bands and services.

What is the agreement reached at WRC-19?

The agreement reached at WRC-19 established regulatory procedures for the deployment of non-GSO systems, including mega-constellations in low-Earth orbit.

How many satellites does SpaceX have?

SpaceX proposed a satellite system comprised of 4,425 satellites and was granted authority to use frequencies in the Ka (20/30 GHz) and Ku (11/14 GHz) bands to provide global Internet connectivity. The Memorandum Opinion, Order and Authorization outlines the conditions under which SpaceX is authorized to provide service using its proposed NGSO FSS satellite constellation. Specifically, the Order specifies the conditions to ensure compliance with Commission rules, and to protect other operations in the requested frequency bands.

What is 3.5 network?

The “3.5 network” assumption was grounded in technical analysis conducted in the 1999-2000 timeframe regarding the number of NGSO satellites that could operate simultaneously without causing prohibitive levels of self-interference. There simply is no basis for continued use of that assumption today. Indeed, in the current Ka-band processing round, the Commission is faced with the possibility of either licensing or granting United States market access to eleven NGSO FSS systems with over 5,600 spacecraft, many of which systems could contribute to the aggregate EPFD received by any given GSO FSS network from co-channel NGSO FSS operations. The same situation exists with respect to the nine NGSO systems proposed in the current V-band processing round that would have over 17,000 spacecraft. Notably, applicants have proposed constellations that vary considerably in size, orbital parameters, coverage, and functionality, and that differ from the parameters underlying the technical analysis conducted twenty years ago.

How long does NGSO last?

Notably, these NGSO systems have expected lifetimes of fifteen years or more. As such, there may be no realistic opportunity to adjust that framework again in the near future. The record reflects widespread recognition of the need to ensure that NGSO system operations do not adversely impact GSO operations.

How many NGSO systems are there in the Ka band?

More specifically, the Commission is now faced with the possibility of authorizing eleven NGSO systems in the current Ka-band processing round alone, and nine NGSO systems in the V-band. The Commission has never before licensed a single stand-alone NGSO network in the V band, let alone nine stand-alone NGSO networks with well over 17,000 NGSO spacecraft.

How does warehousing hinder the availability of services to the public?

Such warehousing can hinder the availability of services to the public by deterring entry by another party committed and able to proceed. S The Notice proposed to relax the six-year milestone requirement for NGSO systems to afford operators greater flexibility with system design and implementation, in light of proposals to launch and operate thousands of satellites.

How far is a geostationary satellite?

Geostationary Earth Orbit (GEO) satellites (orbiting at a distance of 35 786 km in the equatorial plane of the Earth), for their part, …

Why are satellites in low Earth orbit?

Because of their altitude and low latency,

What does OFCOM propose?

Ofcom proposes new checks on interference risks when it considers NGSO license applications and more powerful tools to deal with them if they emerge.

Does Starlink have a satellite?

Starlink, OneWeb and Kepler have existing “Satellite (Earth Station Network)” licenses under Ofcom for operating in the U.K.

Do NGSO operators have to coordinate their networks?

NGSO operators are required to coordinate their networks under International Telecommunication Union (ITU) radio regulations; however, Ofcom pointed to how “in many cases” these arrangements have not yet concluded.

When will OFCOM release its licensing changes?

Following this consultation period, Ofcom plans to confirm and implement licensing changes in a public statement that will be published before the end of 2021.

Is it difficult to operate NGSO?

It is increasingly difficult for companies to agree on how to operate their NGSO networks without causing harmful radio interference to each other, Ofcom warned in a July 26 consultation document it issues before creating new rules.

Is there an exemption for user terminals in Ka-band?

To ensure all relevant satellite equipment becomes subject to the updated rules, it is also removing an existing license exemption for user terminals that are being developed to operate in Ka-band.