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Low-Earth Orbit Satellites: Spectrum Access Digital Transformation Monitor Low-Earth Orbit satellites: Spectrum access July 2017 Internal Market, Industry, Entrepreneurship and SMEs Low-Earth Orbit satellites: Spectrum access © 3Dsculptor/Shutterstock.com Traditionally, geo stationary satellites located at more than 36,000 km above the earth have been used to provide satellite communication to a wide area. An alternative approach however, once unsuccessfully tried in the past is now surfacing again. The idea is to use considerably massive constellation of satellites at lower altitudes to both densify the network and reduce latency. Although technically feasible, those numerous projects come with challenges and access to spectrum is one of them. At stake, the possibility to provide enough capacity at the right price points to serve markets that remain up to now unserved. The cost of such solution however Above all, mobile terrestrial remains important in the absolute and communication systems were about to 1 solutions are regularly looked after be launched all over the world and all of tomake this solution more and more a sudden what was supposed to be a affordable revolutionary service was turned into a Why are Low Earth more expensive and technically less Already tried in the past but more interesting offer than the then exploding Orbit game prone to succeed today GSM. In the end, few low Earth orbit In the 1990’s, several players came with constellations were launched and at the changers? the idea of launching a multitude of beginning of 2000, most LEO projects satellites in low Earth orbit (LEO) with had been dropped or had gone bankrupt, Because of their high position above the the aim of providing communication only to be purchased by investors at a earth, satellites are very effective in services at low cost. fraction of the initial cost. providing wide coverage. Indeed when one cellular antenna on earth covers only Instead of using only a few high After that, it became pretty clear in the a few square km, one satellite, depending orbit satellites, especially geostationary industry that the geostationary satellite, on its elevation covers thousands of orbits where satellites have fixed with its wide-coverage capacities and its square km. positions relative to the Earth (at an more recent high throughput system elevation of around 36,000 km), the idea capabilities were the solution to This explains why, when terrestrial was to place smaller and lighter satellites providing communication services in a infrastructures have not been deployed, orbiting at lower altitude (in the range of world with demand increasing by the satellite is usually seen as a better 180 km to 2,000 km) and thus drastically day for broadband speeds anytime, economic and practical solution to bring reduce the cost of the solution because of anywhere. coverage to areas that would otherwise satellite less expensive to manufacture be left completely unserved. Fundamentally however the very and launch. This however came with concept of LEO communication satellites challenges, both technical and financial. was not dead. While the economic interest of providing voice and Figure 1: Presentation of LEO, MEO and GEO orbits narrowband coverage from a low elevation satellite position was not demonstrated, the idea of using LEO position to provide broadband access surfaced few years ago with several announcements from yet unknown players at that time. Technological progress had been made and the market prospect also had changed. If one satellite with a very broad coverage makes sense for narrowband usage, is it powerful enough to provide broadband capacity for a market that is still largely not served? Source: Communication satellites by William Stalling (2001) (1) 2 Low-Earth Orbit satellites: Spectrum access LEO: Densifying the network to bring Similarly, with a densified network, the most likely to succeed, except maybe increased capacity and reduced capacity is much more increased because for OneWeb, whose status is already well latency of more important frequency reuse advanced with 1.7 billion USD of funding capacity. By adding more satellites in the already secured. Reduced coverage as compared to GEO… constellations, capacity and as a result Globally, the full completion of all the The elevation that characterizes LEO has throughput per user can be easily added LEO projects would result, a direct impact on coverage. At an at a marginal cost. approximately, in more than 17,000 elevation of 36,000 km, coverage from a Who makes what? Which players, satellites in various LEOs providing a satellite is 2.7 wider than it is at 1000km total aggregated capacity of more above the surface of the Earth. When which markets? than150 Tbps. The main question that is three satellites are required to cover the Several new entrants not linked to raised here is whether there are enough Earth on GEO, at least 15 are required to traditional satellite players places on the market for all those cover the whole Earth on LEO. Since players.Most probably, only a few satellites at this elevation are moving, players will succeed in launching their many more are required to provide 17,000 satellites for more constellation. constant coverage. than 150 Tbps Backhauling, consumer and enterprise … But reduced latency and increased broadband as main markets capacity Among the more than 15 LEO projects Given their characteristic, LEO are But the lower elevation of LEO satellite that have surfaced in the last 3 years, a particularly relevant for use cases where constellation also has benefits. Indeed, number of new players is vying to launch large capacity is required. Not since satellites are closer to the Earth new constellation projects focusing on a surprisingly, most ambitious projects in than GEO satellites, the trip time market where high capacity and high their size focus on broadband between the ground and the satellite and throughputs are required. applications, something that can be the satellite and the ground is The three most publicized projects in served with different approaches: significantly reduced and so is the this regard are OneWeb, LeoSat and latency, which is one of the caveats of SpaceX initiatives. The latter has Through mobile backhauling: in areas GEO satellites in general. Latency is received much press because of its CEO where terrestrial backhauling is too critical for real time applications, of Elon Musk, also funder of Tesla, who costly to deploy. which VoIP notably. envisions sending people to Mars. Fixed Broadband access for B2C in SpaceX is also known for the remote/unserved/underserved areas development of a launcher, whose 1st including in emerging markets. stage can be reused (3). Typical latency of GE0 vs LEO: Broadband for high mobility This capability is aimed at further applications (trains, planes, boats). reducing the cost of launching satellite to 280 vs 20 ms (2) space. The fact that these projects have Dedicated governmental, scientific and been the most talked about does not enterprise connectivity. however necessarily mean that they are M2M and imaging targeted by other players While broadband focused projects have Figure 2: Main broadband-focused LEO constellations gotten much of the highlight, M2M, asset tracking and imaging are also targeted by other kind of players. The only three LEO projects of the 2000s to have survived after bankruptcy (Iridium, Orbcomm and Globalstar) have already launched a second generation of satellite to replace the first one. They, still focus on M2M and relatively narrowband applications (voice, messaging). Those projects thus require less satellite. Iridium NEXT for instance will have 66 operational satellites. As for imaging, this market has been invested by new players, often start-ups leveraging very low cost micro satellites. Planet is one of them. It aims at photographing the earth every day and thus take quasi real time imagery. Those updates will be critical for cartography and will pave the way for new innovative applications based on low cost earth Source: IDATE observation. 3 Low-Earth Orbit satellites: Spectrum access Figure 5: Market potential compared, by technology in low-density areas 2 How will LEO constellations fare with competition Source: IDATE Which impact of LEO constellation projects on the satellite industry? As another comparison point, Eutelsat Is 5G an opportunity or a threat for Because most ambitious LEO projects in expect to lower its CapEx required to the satellite industry? figures are carried out by new players provide 1 Gbps to this same 1 million The biggest competition however may (i.e. not traditional GEO operators), LEO USD threshold in the mid term (4). is often seen as a potential disruption in not come from the satellite industry but the industry together with the Figure 4: OneWeb vs ViaSat 3 from the further expansion of terrestrial technologies it involves. With their communication itself through 5G. If LEO capability to drastically reduce the cost projects can help decrease the cost of to deliver 1 Gbps, LEO could indeed satellite connectivity significantly, it still further increase a price competition that cannot compete with terrestrial network is already installed in some markets and when fixed infrastructures are already is causing financial difficulties even to there (backbone and backhaul). This is a biggest satellite operators on the market threat for the viability of LEO projects. (Intelsat, Eutelsat, SES…) Using satellite and especially LEO as a If we look at estimated CapEx to deliver a Complementarities between LEO and backhauling technology will be a way to complement rather than compete with Gbps, we indeed see a sizeable difference GEOSource: exist IDATE between OneWeb for instance and a such movement should operator really However, confrontation between orbits traditional GEO satellite operator. When decide to bridge the connectivity gap. holds true only if LEO, MEO and GEO OneWeb would invest 260,000 USD to Because 5G will use frequency bands players remain distinct.
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