5 ms·

Can someone explain to me the economics/ technology of Starlink and why it beats out traditional geosynchronous internet providers? Is it that owning your own c

by DGAP 6y ago

Can someone explain to me the economics/ technology of Starlink and why it beats out traditional geosynchronous internet providers? Is it that owning your own cheap launch platform makes launching lots of satellites instead of one big one feasible? Is it some new antenna miniaturization technology? If that were the case, I would think this would have been invented by one of the myriad existing players in the space. Why is this apparently revolutionary progress in internet satellite technologies coming out of nowhere from a company (SpaceX) that has nothing to do with connectivity or satellites?

jasonpeacock 6y ago
It's all about latency. Having broadband with 200+ms of latency to reach geostationary satellites is to slow for modern networks. https://www.satsig.net/latency.htm https://www.satsig.net/latency.htm You have to move the satellites closer to Earth to reduce latency - hence low earth orbit (LEO). You can achieve much better latencies, <20ms, and support modern networking applications. https://arstechnica.com/information-technology/2020/03/musk-says-starlink-isnt-for-big-cities-wont-be-huge-threat-to-telcos/ https://arstechnica.com/information-technology/2020/03/musk-... But when you reduce the height to LEO, not only are the satellites no longer geostationary, they also have a much smaller coverage area. So you need more satellites to cover the same area, and fancy networking to handle the constant hand-off between satellites.
- tachyonbeam 6y ago
  Bandwidth as well. Starlink can reach 100Mbps, and they're talking about 200Mbps. They can do that in part because they have more satellites.
  - mbreese 6y ago
    > because they have more satellites I wouldn't characterize this as a function of having more satellites, but rather having fewer users per satellite (an admittedly subtle difference). But, related to the above post(s), the smaller geographical area each satellite covers is a problem for coverage (you need more satellites in orbit), but is a benefit for speed -- you have less users vying for the full bandwidth of the satellite. And, because the geographical areas are smaller, instead of having one base station/uplink, you now have geographically distributed base stations, so you have multiple points to access the Internet. This also helps with bandwidth (instead of X total uplink capacity, you need X/n capacity for each site, where n is the number of sites). Once you get around the logistics of managing a fleet of satellites, many, many benefits flow from having lower orbits.
- Groxx 6y ago
  To grab a couple bits of info from that page + google, to give people a good idea of the distances involved at a glance: Starlink orbit: 550km Geosynchronous orbit: 35,786km Earth's circumference: 40,075km Geosynchronous orbits are quite a way out. Latency at terrestrial distances can be painful already, bouncing through geosynchronous satellites will be multiples worse at a minimum. Meanwhile, Starlink's are at "normal" distances for networking - you probably connect to things further away all the time already.
- nereye 6y ago
  The low latency is also a requirement to receive FCC subsidies related to rural broadband, e.g. see https://www.reddit.com/r/spacex/comments/h04on0/fcc_just_voted_to_allow_starlink_to_bid_on_low/ https://www.reddit.com/r/spacex/comments/h04on0/fcc_just_vot.... Have heard (IIRC in https://theamphour.com/518-satellites-and-evs-with-joris-aerts/ https://theamphour.com/518-satellites-and-evs-with-joris-aer...) that this could have been part of the reason for Starlink's decision to have their satellites in a lower orbit. The subsidy angle is also of course a familiar playbook across SolarCity/Tesla/SpaceX etc.
Rebelgecko 6y ago
SpaceX is super heavily vertically integrated which probably helps a lot with the financials. Also note that their financials aren't public, so there's all kinds of funny possibilities (what if SpaceX launches are sold below cost as a loss leader?) I'd also imagine that they need a TON of subscribers to make it profitable. However by commoditizing their satellites the marginal cost of improving coverage is low (compared to GEO where every satellite is a billion dollar bespoke system). Phased array antennas have been around for a while but I wouldn't be surprised if the starlink terminal is the first consumer device to actually use them (other than maybe boat radars?). They're still pretty expensive.
- wlll 6y ago
  When you say boat radar and phased array, what is your experience there? The only radar I've seen on a boat has one of those spinning antennas.
  - jasonpeacock 6y ago
    No moving parts required, but you do need multiple units pointed in different directions to get full coverage: https://en.wikipedia.org/wiki/Active_phased_array_radar https://en.wikipedia.org/wiki/Active_phased_array_radar
  - Rebelgecko 6y ago
    My experience is poor memory :) After looking into it a bit, it seems that only the military is using phased array radars on boats. I think I misremembered an article about Garmin and Raytheon introducing solid state radars a few years ago
- bigbubba 6y ago
  I've heard it suggested that Starlink is used by SpaceX to keep their schedule fully booked, which helps them maintain quality standards, training, etc. If so, they could perhaps lose money on Starlink but still come out ahead when you factor in the benefit of having experienced workers for whom building and launching rockets is routine.
mlindner 6y ago
It's because of the altitude of the satellites. Normal geostationary satellites are required to be at 35,786 kilometers in altitude above Earth's equator. Any signal has to travel that distance 4 times for a round trip ping, which equates to a minimum ping time to any service of 477 ms simply defined by laws of physics. 477 ms means any online games are unplayable and loading an ssl connection is going to push you into over a second delay. Now the obvious idea is to put the satellites much closer to Earth, in that case they're rapidly moving across the surface and you need thousands/hundreds of them for full coverage, depending on the altitude the satellites are at. This wasn't really feasible until you had a rocket and satellite manufacturing designed for dumping large quantities of satellites into orbit at a time.
fancy_pantser 6y ago
> If that were the case, I would think this would have been invented by one of the myriad existing players in the space. A hundred-dollar bill is lying on the ground. An economist and an engineer walk past it. The economist nods at it and opines: "I thought I saw something over there, but I must've imagined it. If there had been $100 on the ground, someone would've taken it by now." The engineer picks it up.
- jdmichal 6y ago
  I feel like this joke would be improved by the engineer instead responding, "Yea, I did."
endymi0n 6y ago
In the end, it's all of that and more. Geosynchronous is just too far away for good latency, plus the signal is weak and the bandwidth is saturated quickly. So low earth orbit it is, but that meant doing several technology breakthroughs never seen before and at massive consumer scale. First, you need to have massive launch capacity, otherwise satellites wouldn't be in view for most of the world, most of the time. At this ground relative speed, they also stay in view pretty short at that speed, so you need to continuously roam from one satellite to the next every few minutes, hence the need for the cutting edge antenna array. Lastly you need a truckload of satellites. Even the largest fleets are small series productions with specialized, expensive equipment such as radiation hardened processors, flywheels and propulsion to keep in orbit. Mass producing these from commercially available hardware was the third large challenge here. Most companies would go bankrupt just tackling one of these and Starlink pulled them off in parallel. Pretty wicked.
njarboe 6y ago
It is due in part to them owning a cheap launch platform. The world has not caught up yet to how cheap space launches are going to be. SpaceX knew that with their Falcon 9 reusable rockets that launch costs for them were going to go down by a factor of 10 and with their new SuperHeavy, by a factor of 1000. Think $30/kg to orbit instead of $10000/kg. 14 of the 23 rockets launched by SpaceX this year were for Starlink. They want to build up a culture and skills for rapid relaunch and building StarLink gives them a hopefully profitable way to drive that. Phased array antennas are necessary for this to work (no tracking of the low satellites necessary), because one wants to have the satellites in very low orbits to achieve low latency. Geosynchronous satellites are very far away from earth so that speed of light gives unacceptable delays for things like gaming, chats, remote server admin, etc. Very low orbit can get short pings (in theory better than fiber because light moves faster in a vacuum than in glass). But very low orbit means one needs a lot of satellites to have wide coverage and no dropped connections. They are thinking around 12,000 in the first phase and around 42,000 in the second phase. Having so many satellites also gives the system much higher bandwidth as each satellite is limited in data transfer rates. Plus SpaceX is looking for a cash cow to fund their ultimate goal: a cheap, extensive Mars transportation system to facilitate building a city on Mars.
- GuB-42 6y ago
  I agree with the cheap launch platform argument but from another, perspective. I don't believe SpaceX numbers and BFR (it will always be BFR for me) is still a paper rocket (Raptor looks good though). But it is still cheap compared to traditional launches. The problem is: SpaceX has now plenty of cheap, reusable Falcon 9s but not a lot of stuff to launch. There are not that many companies who want to build and launch satellites: it is expensive no matter what and the cost has to be justified. Falcon 9 rockets (including heavy) are also limited in capability: small fairing space and not the most efficient beyond LEO. Also, it may not be suitable for some sensitive payloads (military, etc...). Ii means that SpaceX has good rockets, they already have the "culture and skills for rapid relaunch" but not enough market for it. So they did the obvious thing: create their own. As for BFR. I made the choice not to take SpaceX communication into account, it is worthless. Same thing with everything by Elon Musk. I only believe what they show, which is already impressive enough.
deleted 6y ago
[deleted]
maccam94 6y ago
Building on the other comments here, SpaceX has more knowledge and certainty about recent and upcoming launch economics than other satellite providers, which opened up the possibility of a system like Starlink. Starlink is capable of such higher bandwidth and lower latency due to its lower orbit. Each satellite has a fixed amount of bandwidth capacity, and the area it covers is based on how high it is (how much of the Earth it can see at one time). High orbits mean they cover more area and spread that bandwidth out between more customers, low orbits mean less coverage area per satellite (so you need lots of satellites for global coverage) but more bandwidth per customer in that area.
ryanmarsh 6y ago
What I don’t see talked about enough (in relation to SpaceX) is the one big customer who has been wanting global high bandwidth/low latency since at least the 90’s. That is the US military. Think drones and all the fancy battle space information management stuff they’ve been talking about forever. I don’t see how this gets built without the US mil wanting to use it. Furthermore I don’t see how this was designed without their input. It’s entirely possible that the US govt is covertly funding Starlink.
- SergeAx 6y ago
  I believe even now hundreds of millis latency is quite enough for military applications, not even speak of 90's. There's also a caveat: currently a satellite should have a ground station in view to relay data. It is rarely the case in areas of military activity.

by DGAP 6y ago

jasonpeacock 6y ago

It's all about latency. Having broadband with 200+ms of latency to reach geostationary satellites is to slow for modern networks. https://www.satsig.net/latency.htm https://www.satsig.net/latency.htm You have to move the satellites closer to Earth to reduce latency - hence low earth orbit (LEO). You can achieve much better latencies, <20ms, and support modern networking applications. https://arstechnica.com/information-technology/2020/03/musk-says-starlink-isnt-for-big-cities-wont-be-huge-threat-to-telcos/ https://arstechnica.com/information-technology/2020/03/musk-... But when you reduce the height to LEO, not only are the satellites no longer geostationary, they also have a much smaller coverage area. So you need more satellites to cover the same area, and fancy networking to handle the constant hand-off between satellites.

tachyonbeam 6y ago
Bandwidth as well. Starlink can reach 100Mbps, and they're talking about 200Mbps. They can do that in part because they have more satellites.
- mbreese 6y ago
  > because they have more satellites I wouldn't characterize this as a function of having more satellites, but rather having fewer users per satellite (an admittedly subtle difference). But, related to the above post(s), the smaller geographical area each satellite covers is a problem for coverage (you need more satellites in orbit), but is a benefit for speed -- you have less users vying for the full bandwidth of the satellite. And, because the geographical areas are smaller, instead of having one base station/uplink, you now have geographically distributed base stations, so you have multiple points to access the Internet. This also helps with bandwidth (instead of X total uplink capacity, you need X/n capacity for each site, where n is the number of sites). Once you get around the logistics of managing a fleet of satellites, many, many benefits flow from having lower orbits.
Groxx 6y ago
To grab a couple bits of info from that page + google, to give people a good idea of the distances involved at a glance: Starlink orbit: 550km Geosynchronous orbit: 35,786km Earth's circumference: 40,075km Geosynchronous orbits are quite a way out. Latency at terrestrial distances can be painful already, bouncing through geosynchronous satellites will be multiples worse at a minimum. Meanwhile, Starlink's are at "normal" distances for networking - you probably connect to things further away all the time already.
nereye 6y ago
The low latency is also a requirement to receive FCC subsidies related to rural broadband, e.g. see https://www.reddit.com/r/spacex/comments/h04on0/fcc_just_voted_to_allow_starlink_to_bid_on_low/ https://www.reddit.com/r/spacex/comments/h04on0/fcc_just_vot.... Have heard (IIRC in https://theamphour.com/518-satellites-and-evs-with-joris-aerts/ https://theamphour.com/518-satellites-and-evs-with-joris-aer...) that this could have been part of the reason for Starlink's decision to have their satellites in a lower orbit. The subsidy angle is also of course a familiar playbook across SolarCity/Tesla/SpaceX etc.

Rebelgecko 6y ago

SpaceX is super heavily vertically integrated which probably helps a lot with the financials. Also note that their financials aren't public, so there's all kinds of funny possibilities (what if SpaceX launches are sold below cost as a loss leader?) I'd also imagine that they need a TON of subscribers to make it profitable. However by commoditizing their satellites the marginal cost of improving coverage is low (compared to GEO where every satellite is a billion dollar bespoke system). Phased array antennas have been around for a while but I wouldn't be surprised if the starlink terminal is the first consumer device to actually use them (other than maybe boat radars?). They're still pretty expensive.

wlll 6y ago
When you say boat radar and phased array, what is your experience there? The only radar I've seen on a boat has one of those spinning antennas.
- jasonpeacock 6y ago
  No moving parts required, but you do need multiple units pointed in different directions to get full coverage: https://en.wikipedia.org/wiki/Active_phased_array_radar https://en.wikipedia.org/wiki/Active_phased_array_radar
- Rebelgecko 6y ago
  My experience is poor memory :) After looking into it a bit, it seems that only the military is using phased array radars on boats. I think I misremembered an article about Garmin and Raytheon introducing solid state radars a few years ago
bigbubba 6y ago
I've heard it suggested that Starlink is used by SpaceX to keep their schedule fully booked, which helps them maintain quality standards, training, etc. If so, they could perhaps lose money on Starlink but still come out ahead when you factor in the benefit of having experienced workers for whom building and launching rockets is routine.

mlindner 6y ago

It's because of the altitude of the satellites. Normal geostationary satellites are required to be at 35,786 kilometers in altitude above Earth's equator. Any signal has to travel that distance 4 times for a round trip ping, which equates to a minimum ping time to any service of 477 ms simply defined by laws of physics. 477 ms means any online games are unplayable and loading an ssl connection is going to push you into over a second delay. Now the obvious idea is to put the satellites much closer to Earth, in that case they're rapidly moving across the surface and you need thousands/hundreds of them for full coverage, depending on the altitude the satellites are at. This wasn't really feasible until you had a rocket and satellite manufacturing designed for dumping large quantities of satellites into orbit at a time.

fancy_pantser 6y ago

> If that were the case, I would think this would have been invented by one of the myriad existing players in the space. A hundred-dollar bill is lying on the ground. An economist and an engineer walk past it. The economist nods at it and opines: "I thought I saw something over there, but I must've imagined it. If there had been $100 on the ground, someone would've taken it by now." The engineer picks it up.

jdmichal 6y ago
I feel like this joke would be improved by the engineer instead responding, "Yea, I did."

endymi0n 6y ago

In the end, it's all of that and more. Geosynchronous is just too far away for good latency, plus the signal is weak and the bandwidth is saturated quickly. So low earth orbit it is, but that meant doing several technology breakthroughs never seen before and at massive consumer scale. First, you need to have massive launch capacity, otherwise satellites wouldn't be in view for most of the world, most of the time. At this ground relative speed, they also stay in view pretty short at that speed, so you need to continuously roam from one satellite to the next every few minutes, hence the need for the cutting edge antenna array. Lastly you need a truckload of satellites. Even the largest fleets are small series productions with specialized, expensive equipment such as radiation hardened processors, flywheels and propulsion to keep in orbit. Mass producing these from commercially available hardware was the third large challenge here. Most companies would go bankrupt just tackling one of these and Starlink pulled them off in parallel. Pretty wicked.

njarboe 6y ago

It is due in part to them owning a cheap launch platform. The world has not caught up yet to how cheap space launches are going to be. SpaceX knew that with their Falcon 9 reusable rockets that launch costs for them were going to go down by a factor of 10 and with their new SuperHeavy, by a factor of 1000. Think $30/kg to orbit instead of $10000/kg. 14 of the 23 rockets launched by SpaceX this year were for Starlink. They want to build up a culture and skills for rapid relaunch and building StarLink gives them a hopefully profitable way to drive that. Phased array antennas are necessary for this to work (no tracking of the low satellites necessary), because one wants to have the satellites in very low orbits to achieve low latency. Geosynchronous satellites are very far away from earth so that speed of light gives unacceptable delays for things like gaming, chats, remote server admin, etc. Very low orbit can get short pings (in theory better than fiber because light moves faster in a vacuum than in glass). But very low orbit means one needs a lot of satellites to have wide coverage and no dropped connections. They are thinking around 12,000 in the first phase and around 42,000 in the second phase. Having so many satellites also gives the system much higher bandwidth as each satellite is limited in data transfer rates. Plus SpaceX is looking for a cash cow to fund their ultimate goal: a cheap, extensive Mars transportation system to facilitate building a city on Mars.

GuB-42 6y ago
I agree with the cheap launch platform argument but from another, perspective. I don't believe SpaceX numbers and BFR (it will always be BFR for me) is still a paper rocket (Raptor looks good though). But it is still cheap compared to traditional launches. The problem is: SpaceX has now plenty of cheap, reusable Falcon 9s but not a lot of stuff to launch. There are not that many companies who want to build and launch satellites: it is expensive no matter what and the cost has to be justified. Falcon 9 rockets (including heavy) are also limited in capability: small fairing space and not the most efficient beyond LEO. Also, it may not be suitable for some sensitive payloads (military, etc...). Ii means that SpaceX has good rockets, they already have the "culture and skills for rapid relaunch" but not enough market for it. So they did the obvious thing: create their own. As for BFR. I made the choice not to take SpaceX communication into account, it is worthless. Same thing with everything by Elon Musk. I only believe what they show, which is already impressive enough.

deleted 6y ago

[deleted]

maccam94 6y ago

Building on the other comments here, SpaceX has more knowledge and certainty about recent and upcoming launch economics than other satellite providers, which opened up the possibility of a system like Starlink. Starlink is capable of such higher bandwidth and lower latency due to its lower orbit. Each satellite has a fixed amount of bandwidth capacity, and the area it covers is based on how high it is (how much of the Earth it can see at one time). High orbits mean they cover more area and spread that bandwidth out between more customers, low orbits mean less coverage area per satellite (so you need lots of satellites for global coverage) but more bandwidth per customer in that area.

ryanmarsh 6y ago

What I don’t see talked about enough (in relation to SpaceX) is the one big customer who has been wanting global high bandwidth/low latency since at least the 90’s. That is the US military. Think drones and all the fancy battle space information management stuff they’ve been talking about forever. I don’t see how this gets built without the US mil wanting to use it. Furthermore I don’t see how this was designed without their input. It’s entirely possible that the US govt is covertly funding Starlink.

SergeAx 6y ago
I believe even now hundreds of millis latency is quite enough for military applications, not even speak of 90's. There's also a caveat: currently a satellite should have a ground station in view to relay data. It is rarely the case in areas of military activity.