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Simulation of OneWeb, SpaceX and Telesat's proposed global broadband constellations (January 2019)
Inigo del Portillo and his colleagues at MIT have run a simulation comparing OneWeb, SpaceX and Telesat's proposed LEO Internet service constellations. They estimated the average data rate per satellite and total system throughput (sellable capacity) for each constellation then computed the number of ground stations needed to achieve full capacity. The simulations were run with and without ISLLs. The configurations of SpaceX and OneWeb's constellations have changed somewhat since they ran the simulations, but del Portillo does not think the numbers for total throughput and number of ground stations would vary a lot for SpaceX and he expected the total system throughput would decrease slightly for OneWeb because of the reduction of the number of satellites from the initial 720 to 600.
Fifteen-dollar, electronically-steerable antennas for satellite and terrestrial connectivity (February 2019)
OneWeb founder Greg Wyler announced that his self-funded side project, Wafer LLC, has developed a flat, low-power phased-array antenna that could be mass-produced for $15. If that is the case, we can look forward to end-user terminals in the $2-300 dollar range. At this cost, one can envision deploying large numbers of two-antenna user terminals to act as ground stations when they are otherwise idle. A recent simulation shows that doing so would result in lower latency and jitter than today's terrestrial networks. Owners of these relay terminals could be subsidized.
Google balloons and Telesat satellites (February 2019)
Telesat will use Google's network operating system. In return, Google, which is also a SpaceX investor, may get access to some Telesat data in addition to compensation for their software. Another intriguing possibility is that Google might be planning to integrate Project Loon, their stratospheric balloon Internet service with Telesat's LEO satellite Internet service -- to use Telesat's network as a global backbone. That integration would be facilitated by their both running the same SDN software -- the same network operating system. (In the long run, I expect that all network layers will be integrated -- from the ground to airplanes to geostationary orbit).
SpaceX's Starlink Internet service will target end-users on day one (March 2019)
Starting with Teledesic in 1990, would-be LEO satellite constellations have pitched their projects to the FCC, other regulators, and the public as a means of closing the digital divide, but they also have their eyes on lucrative aviation, maritime, high-speed trading, mobile backhaul, enterprise, and governments markets. (LEOSat, which had planned to focus exclusively on the enterprise and government markets recently suspended operations). SpaceX has filed an FCC application for one million ground stations, indicating that they will be focused on end-users and small organizations in addition to high-end customers from the start.
Are inter-satellite laser links a bug or a feature of ISP constellations? (April 2019)
OneWeb has decided not to include ISLLs in the first phase of their constellation and SpaceX will not introduce them until near the end of 2020, at which time they may start with test satellites. OneWeb's decision was motivated by political issues in Russia as well as technical considerations. They will need more ground stations to offer global service without ISLLs and a team of MIT researchers has run a simulation of a 720-satellite OnWeb constellation. They estimate that 71 ground stations would be required to reach maximum throughput.
Amazon's orbiting infrastructure (April 2019)
In his first annual stockholder letter, Amazon CEO Jeff Bezos stressed that Amazon was focused on investing in infrastructure. Initially, they invested in retail distribution centers but have added an Internet backbone, trucks and planes, third party retail support, cloud computing and storage, and satellite launch and ground station service and are now working on a constellation of LEO satellites for broadband service. They use this infrastructure themselves and market it to competitors like online retailers and they have contracts to launch satellites for OneWeb and Telesat. This infrastructure yields both revenue and access to market data and there have been calls for antitrust action against Amazon.
Satellite Internet Service Progress by SpaceX and Telesat (May 2019)
Telesat has signed their first LEO customer, Omniaccess a provider of connectivity to the superyacht market, received a subsidy from the Canadian budget for providing service in rural Canada, is working with two teams that are competing to be the prime contractor for their constellation, and signed a launch contract with Amazon's Blue Origen. They also announced that they had demonstrated 5G mobile backhaul in tests with Vodaphone and the University of Surrey. SpaceX also announced ambitious plans for future launches, which have subsequently been surpassed.
SpaceX reports significant broadband satellite progress (May 2019)
SpaceX announced a significant reduction in the size and weight of their satellites and the addition of krypton-powered thrusters that would enable them to autonomously avoid collisions with on-orbit debris that was large enough to track. The thrusters would also be used to de-orbit obsolete satellites. Might the collective constellation "learn" to avoid smaller debris one day?
Might satellite constellations learn to avoid debris with sensors on satellites? (May 2019)
According to the European Space Agency, there are about 5,000 orbiting satellites, about 40% of which are still functioning. They estimate that there have been over 500 break-ups, explosions, collisions, or anomalous events resulting in fragmentation and they estimate that there are 34,000 debris objects >10 cm, 900,000 from 1 to 10 cm and 128 million from 1 mm to 1 cm. NASA says there are more than 20,000 pieces of debris larger than a softball, 500,000 the size of a marble or larger and many millions so small they can’t be tracked. Space debris is a "tragedy of the commons." SpaceX plans to launch thousands of satellites. Could sensors on satellites detect and catalog small pieces of debris and, if so, could that lead to meaningful evasive action?
Hongyun Project -- China's low-earth orbit broadband Internet project (June 2019)
China has announced two LEO broadband satellite projects and a LEO narrowband Internet of things constellation. While far behind SpaceX in technology, the Chinese companies have a large domestic market, access to government capital and political and economic ties to many nations through their Belt and Road and Digital Silk Road infrastructure projects.
Amazon's AWS Ground Station service is now available (June 2019)
Amazon is offering satellite ground station access as a service. They list a number of advantages to their service, several of which are based on complementary Amazon offerings like access to their data centers and global network backbone and cloud computing and storage services. We can assume that Amazon's satellite constellation will use these ground stations at cost and, like their launch service, they will be made available to competitors. Amazon has been accused of predatory pricing in retail and competing ground-segment companies may fear the same.
Latecomer Amazon will be a formidable satellite ISP competitor (July 2019)
In spite of being a latecomer to the race to deploy a constellation of LEO broadband Internet satellites, Amazon's Project Kuiper will be a formidable competitor. While far behind SpaceX, Amazon has in-house launch capability and they have extensive complementary infrastructure including data centers, Web services, and a ground-station service. They also have the funds to finance the constellation as well as to develop or acquire critical technology like ISLLs and cost-effective phased-array antennas. They have also hired ex-SpaceX executives and engineers and in Jeff Bezos they have a leader who is comparable to Elon Musk.
An optimistic update from Telesat (August 2019)
Telesat received 685 million Canadian dollars from the government to subsidize rural connectivity. They plan to start service at the end of 2022 with 200 satellites in polar orbit, to add 100 more in inclined orbit in 2023 and perhaps eventually reach 500 satellites. Combining polar and inclined orbits and utilizing the far-north ground stations they already have for their profitable, established geosynchronous satellite service will help them gain a foothold in rural Canada and polar regions.
Inter-satellite laser link update (November 2019)
SpaceX initially planned to have five ISLLs per satellite but cut that back to four due to the technical difficulty of linking to a fast-moving satellite in a crossing plane and the short duration of such links. OneWeb has decided against using ISLLs for the time being due to cost and political considerations and Telesat remains committed to them. SpaceX is engineering its own ISLL hardware, but OneWeb and Telesat may be working with third parties. The situation with Hongyun is unknown and LEOsat has abandoned their effort.
What to expect from SpaceX Starlink broadband service next year and beyond (November 2019)
By the end of 2020, SpaceX will have coverage in the heavily populated parts of the world between around 50 degrees north and south latitude. They expect to be launching 120 satellites a month and, by the end of 2020, the satellites will be equipped with ISLLs. However, by that time they will have many legacy satellites in space and those early ISLLs may just be for testing. They expect the next-generation Starship to be able to place at least 400 Starlink satellites in orbit, reducing the per-satellite cost to 20% of today's 60-satellite launches. They hope to compete with the "crappy" $80/month service in the US and, since the cost of the constellation is fixed, they will strive for affordable prices worldwide.
Starlink simulation shows low latency without inter-satellite laser links (ISSLa) (December 2019)
Mark Handley, a professor at University College London, has made two terrific videos based on runs of his simulation of the first -- 1,584 satellite -- phase of SpaceX Starlink. I discussed the first video, which assumes that the satellites have ISLLs, in a recent post. This one shows that, while not as fast as an equivalent ISLL path, long bent-pipe paths would typically have lower latency than terrestrial fiber routes between the same two points. It also considers the possibility of using end-user terminals as ground stations when they are idle, which would further reduce latency and jitter.
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