Once fully deployed, its goal is to offer download speeds of up to 10 Gbps. In a filing with the US Federal Communications Commission, SpaceX claimed it can currently deliver 100 Mbps download speeds and 20 Mbps upload speed on its existing LEO network, at a cost of $129 CAD per month (in addition to a one-time $649 CAD hardware and installation cost 149). OneWeb expects to launch global commercial services by 2022 148.Ĭurrently, LEO broadband services are advertised to provide significantly higher download and upload speeds relative to comparably priced wireline plans. After a period of difficulties in securing financing, including a bankruptcy filing in March 2020, OneWeb (now owned by a consortium that includes the UK government) has operated a consistent launch schedule, launching its 200th satellite in May 2021. Of these three companies, SpaceX moved to the beta testing stage in October 2020, while Canadian provider Telesat has set the second half of 2023 as its target for launching commercial services 146, 147. The throughput promised also far exceeds that which can be provided by any realistically deployable network infrastructure.ĭue to this, the period from 2018-2021 saw an explosion of satellite broadband providers launching satellites into low Earth orbit, with the most advanced of these moving shortly afterwards to beta testing.Īt the time of writing, the three LEO constellations at the most advanced stage of development are SpaceX’s proposed 4,425 Starlink constellation in the Ku-Ka band, OneWeb’s 720 satellite system in the Ku-Ka band and Telesat’s 298 satellite Lightspeed constellation in the Ka band 145. This has resulted in an increased interest in the possibility of LEO satellites to provide affordable, high-speed and low-latency internet to the Earth’s most remote and unconnected regions. mass production, multiple-payload launches and reusability) have significantly reduced satellite production and launch costs. smaller size and mass, antennae technology, and configurable radio-frequency payload systems) and practices (i.e. Over the past three decades, advances in satellite technology (e.g. These earlier projects failed largely due to the prohibitive manufacturing and launch costs of satellite technology at the time. Earlier LEO projects from companies such as Iridium and Globalstar had previously been proposed in the 1990’s 144. Modern LEO satellite internet proposals were first publicly discussed in 2014. In order to overcome these challenges, satellite operators are required to use a constellation of satellites (with multiple orbits that differ with respect to location and time) to provide global coverage and visibility. Also, due to their high apparent angular velocity, LEO satellites have a smaller “dwell” time (in which the object is visible to one part of the Earth). The primary disadvantages of being deployed in LEO include experiencing some atmospheric drag leading to loss of orbit, and shorter life spans of the satellites. The LEO satellite constellations also offer increased performance due to advanced modulation schemes, multi-beam antennas, and more sophisticated frequency reuse schemes 143. At this altitude, LEO satellites deployed for broadband communications purposes experience a significant advantage with respect to round-trip (~3 milliseconds) and inter-satellite latency, compared to GSO satellites. Low Earth orbit (LEO) satellites are deployed between ~400 and 2,000 km above the surface of the Earth.
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