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SpaceX Wants Permission To Test Satellite Internet
An anonymous reader writes: SpaceX has filed documents with the FCC asking for permission to begin testing a project to serve internet access from space. "The plan calls for launching a constellation of 4,000 small and cheap satellites that would beam high-speed Internet signals to all parts of the globe, including its most remote regions." This follows news that Facebook and Google had stepped back their efforts in that arena. SpaceX could prove to be a better fit for the project, given that they need only rely on themselves for launching satellites into orbit. "The satellites would be deployed from one of SpaceX's rockets, the Falcon 9. Once in orbit, the satellites would connect to ground stations at three West Coast facilities. The purpose of the tests is to see whether the antenna technology used on the satellites will be able to deliver high-speed Internet to the ground without hiccups."
It will have to be Low orbit which is already full of space debris from over 50 years of us jerking around out there. He could go higher but he'll be hit with latency issues if he wants to avoid the bulk of the junk.
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Looks like you may have a new competitor soon.
SJW's don't eliminate discrimination. They just expropriate it for themselves.
Exede and Hughesnet already serve internet from satellites, so we need more? Maybe this one will be better?
If at first you don't succeed... anyway no one has come close to "trying". They just played with the idea for a little. SpaceX could actually launch these satellites using their unsold cargo capacity on paid flights. SpaceX paying just the fuel cost to do the project is much different than say Google having to pay for entire launches.
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I don't think FCC has jurisdiction over "all parts of the globe"
I doubt Musk is looking to create a satellite based Internet service. I think it more likely that he's using this network to serve as a testbed for an interplanetary network that covers Earth Mars. The global Internet service just provides him a way to monetize the project to fund its furthered development.
"Lack of speed can be overcome. In the worst case by patience." --Znork
Google and facebook have realized that some problems are not (economically) surmountable.
The problems are the following: The closer you fly your satelite to the earth, the more resistance it has from the atmosphere. The density of the atmosphere reduces by a factor of 100 each 46 km of height. So at "100km", you have about 10000 times less air than at the surface. Some people call that space. At 200km the air pressure is about 100 million times less than what it is over here. That is enough to have a reasonable decay rate of weeks/months/years. "skylab" came down after a few decades, right?
The further away you fly your satellites, the longer the travel times will be for the signals. This equates to ping-times. Hmm. 200km is 0.6 ms, quite acceptable. Both ways. 1.3ms. Still fine. Double the distance to 400km for slower decay times, and you're still about 10 times faster than a normal ADSL line. Acceptable. Not a problem. (the problem here is the same for everybody. The satellites will then play "pass the hot potato" to one that's flying above the ground station and beam your packet down to earth. Assuming your halfway around the globe, that will be about 10000 km. That's with 66ms (round trip) already more than what you get with a residential ADSL line. Still not too shabby.)
The problem with putting satellites high is that the distance to the user becomes large. You want them as close as possible.
The closer you put them, the more you need. -> 4000 of them. This however is not just a one-time investment: because they are low, their orbits decay and they fall back to earth on relatively short notice. If you need 4000 of them, they are not going to be large. So they are small. If you have a cubesate (10cm cubed) weighing 1kg, its orbit will decay just like a 100kg satellite of 10x100x100cm (flying the wrong side towards the front). But a bigger satellite is likely to be 100x100x100cm and weigh not 100, but 1000kg. The extra weight helps keep it in orbit, the extra size in the flying direction does not make a big difference. So the small satellites decay fast as well!
I'm really hoping that they'll launch another 5001 satellites after the first 4000, because Internet.
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I saw a video of the announcement in Seattle a few weeks ago, and I'm pretty sure he mentioned the number 1,100 km when asked about the altitude. But since then I've heard 6~700 km from another source. Anyway, the idea is to be high enough so that you can join any two points on the globe in only 3~5 hops. He said this would be faster than terrestrial backbone, where you typically have 15 or 20 hops between A and B, each of which adds latency in the form of processing time, not to mention that light travels almost twice as fast in vacuum as it does in fiber.
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https://www.youtube.com/watch?...
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Yes, low orbit is a must.
Over 15 years ago, at the school I worked for, we were offered satellite-based Internet via DirectPC (a DirecTV subsidiary). The speed was amazing by late-1990s standards, 400Kbps sustained! But latency was a killer, at approximately one second minimum. Routing was also nightmarish, as the uplink was phone-based (thus not requiring immense power to transmit, and keeping the lag well, not acceptable, but almost).
I hope "low orbit" is close enough to the Earth to dillute all that latency. Say, if the distance is comparable to what we get in a transatlantic connection, it might just be usable for everything-but-gamers :)
Just re-watching the video: He gets into the specs at around 3:30, citing a goal of 1Gbps @20~30ms latency a couple of minutes later. At around 9:30 he specifically mentions 1100 km for the altitude.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
They will clean themselves up. Low earth orbit has a very small amount of atmosphere, but enough to slow the satellites over time and cause them to re-enter. Most likely they would burn up pretty much completely, though a few pieces might reach the ground.
"It will have to be Low orbit ..."
SES has been offering internet service via geostationary satellites in Europe for over a decade.
http://www.ses-broadband.com/1...
You're right and wrong. He wants a system that covers both Earth and Mars, but he also wants to run a satellite internet service. As he said at the Seattle announcement a few weeks ago, we don't know exactly what we'll need to build a city on Mars, "But one thing's for sure, it'll take a whole lot of money." So he intends to use the ISP satellite network to fund the overall Mars mission.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
Most of those services were aimed at government/corporate customers for high service fees, a relatively small market. If they're able to work out the bandwidth issues, keep the service fee reasonable and not have too much latency the market will have millions, perhaps hundreds of millions of customers. At $35 with even 10 Million global customers that would be $350 Million in revenue a month, or over $4 Billion a year. I think the entire system is supposed to cost somewhere around $10 Billion. With those numbers I have a hard time believing that even with employees, equipment, maintenance, fiber and other costs the venture wouldn't be in the black within 5 years ($20 billion total revenue).
But how long will they stay up there before burning up?
You're right and wrong. He wants a system that covers both Earth and Mars, but he also wants to run a satellite internet service. As he said at the Seattle announcement a few weeks ago, we don't know exactly what we'll need to build a city on Mars, "But one thing's for sure, it'll take a whole lot of money." So he intends to use the ISP satellite network to fund the overall Mars mission.
You know, I have one simple request. And that is to have satellites with frickin' laser beams attached to their heads!!!
If Space-X can't win on merits alone, lasers....
Months to years. It's a feature and a bug. The idea is to make both the satellite and launch cost low enough to where they are essentially disposable. This has some advantages - you don't have to have a sat that stores fuel for a decade and where you have to have overly redundant systems to ensure the thing stays up long enough to make money. But - you have to be able to build them and launch them quick and cheap.
Now, where on this spectrum of things does SpaceX fall?
Faster! Faster! Faster would be better!
The current proposal puts these satellites in a higher LEO, almost MEO orbit of about 750 Miles. They would need some kind of deorbit/graveyard orbit as they would be up there for decades or even centuries on their own. Shouldn't be too difficult though, one option would be to give each satellite a small electrodynamic tether or ion thruster that could be used to keep the satellite positioned correctly and at the end of its service life used to deorbit it.
With spaceX's new proposal you are looking at 2.2 ms as the minimum earth to ground delay + presumably something up to 15-16,000 km (15-16 ms) if your packets had to travel to the exact opposite side of the globe. Add in a 1-2 ms delay for each hop between satellites due to the actual switching and he could be much much much faster for intercontinental packets.
Plus I'm assuming under this scenario that there will be hundreds of terrestrial transmittal points to use versus just a few base stations to make the terrestrial hops even less.
I'd wager that financial market trading traffic alone could pay for a significant portion of this bill at super premium rates, especially overseas traders. Not to mention traffic from ships, planes, rural 1st world locations all paying a premium. They can implement zone pricing pretty easily because they will always be able to able to triangulate a transmission down to the inch. With a network that dense it would greatly surpass the accuracy of the existing GPS constellation.
Yes, due to latency reasons they are probably going to put your satelites in < 1000km altitude.
But if you can do point to point communication via same satelite network without needing to go via base station, or if you have several base stations across the globe, then this will have LOWER latency than going via cables especially for long distance stuff say USA <=> Europe.
I assume they plan to launch small satelites, maybe bigger than cubesats, but definitely smaller than 100cm^3 and 1000kg. I think one rocket should be able to launch a significant percentagle of constellation, otherwise this whole thing becomes unfeasible.
On top of that, you have to weigh the cost of launching a constellation against the cost of laying enough cable to cover the whole world. Satelites are cheaper if you have reusable rockets. And regarding decaying orbit- I think the satelites, no matter what they are now, will be obsolete and replaced in ~10 years anyway, so they just need to last that long.
I wonder how will they deal with scalability with the number of clients, and what kind of antennas will this need on the ground. I imagine they'll have to be somewhat directional, otherwise power usage will be too high? Will they have to be outdoors? How will an individual satelite deal with the load when it passes over a huge city with lots of clients, say NY?
--Coder
Many years ago (mid 2Ks or so), I found that a highway rest area had wifi available. Suspecting that it was geosat-based, I pinged my home server. Yep, just over 1000ms. GEO is about 250ms away as the photon flies, times two for the outbound round trip, and times two again for the response round trip.
The phone uplink for DirectPC was basically a cheat to get rid of one of those round trip delays. Not all satellite internet systems did that, and I can recall seeing pairs of junked interface boxes where the uplink and downlink units were stacked together.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
Only if he calls it the Alan Parsons Project.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
I'd wager that financial market trading traffic alone could pay for a significant portion of this bill at super premium rates, especially overseas traders. Not to mention traffic from ships, planes, rural 1st world locations all paying a premium. They can implement zone pricing pretty easily because they will always be able to able to triangulate a transmission down to the inch. With a network that dense it would greatly surpass the accuracy of the existing GPS constellation.
I had not thought of that idea before in terms of a potential customer for this set-up. That is an excellent point. Iridium could have been used for something like this (which also has a digital data component), but given the technology capabilities available at the time Iridium was being built, they could only get about 4800 baud for individual customers... something that makes the bandwidth latency sort of irrelevant. High bandwidth and low latency combined with global coverage would indeed be a good customer.
The major competitor to this concept in that regard is an even older technology though, mainly the 19th Century concept (updated to using 21st Century materials) of the cable laying ship. An awful lot of fiber cable has been laid down across all of the oceans of the world between major cities. It is only when you can't access that fixed terrestrial network that something of this nature really becomes useful (as you've mentioned).
As a means to deliver that last mile architecture, it really opens up possibilities.
And it is through the International Telecommunications Union (ITU) that most countries coordinate the usage of global spectrum usage. This includes the USA, particularly with regards to almost anything having to do with spaceflight where you have spectrum usage that crosses international boundaries... like will most definitely happen in the case of this satellite constellation.
In the USA, you work through the FCC to make those ITU filings though.
With Geosynch satellites that adds up to roughly 45 milliseconds at a minimum for the signal to get from the base station to the satellite and back down to you.
Your math is wrong. It's 240ms round trip straight-on from the equator, directly below the bird, up to 280ms with both ends at extreme angles. (Damn, I thought it was 250-ish each way, not round trip.) GEO is around 35,000 km, or 70,000km round trip, and the speed of light is about 300,000kps. So that's 7km divided by 30km/sec, or around 233ms, which is pretty close for rounded numbers.
This is exactly why LEO is the holy grail for satellite internet: latency. The downside is they keep moving around and you need a lot of them. Iridium uses 65-70 satellites, but with low, analog bandwidth. Iridium is at 781km, so SpaceX-net will be higher, so a little more delay, but that should improve the view angle a little bit.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
Did you miss reading the bit about "hit with latency issues?" A 1000ms ping time is no fun.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
I bet you believe that oil reserves are a hard number, too, and they don't vary with oil price. By reducing the cost of launches, it becomes affordable to launch things that weren't previously affordable, thus increasing the potential business by lowering the price point.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
Your math is wrong. [satsig.net] It's 240ms round trip straight-on from the equator, directly below the bird, up to 280ms with both ends at extreme angles. (Damn, I thought it was 250-ish each way, not round trip.)
It depends on your definitons of "each way" and "round trip". In particular we don't tend to have servers collocated on the sattelites. so the typical satelite internet scenario is client->sattelite->base station->server->base station->sattelite->client.
So it's a minimum of
120ms client->sat
120ms sat->base
120ms base->sat
120ms sat->client
Assuming delays on the ground are negligable that is a minimum of 480ms round trip time to a server on the internet for a two way geostationary system. Add medium access control protocols that require another round trip to request permission to send a non-trvial ammount of data or significant latency on the ground and that can easilly get much worse. Afaict round trip times of over a second are quite common in practical systems.
In the easly days of sattlite internet it was common to see systems that used sattelite for downstream and dialup for upstream. This significantly reduces the total round trip time (no need for medium access control, only go via the sattelite once but runs into the problem that even assuming asymetric traffic patterns the upstream bandwidth provided by dialup is inadequate by modern standards.
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From those numbers, could one figure out the antenna footprint size on the surface?
You can't calculate it exactly but you can get a rough idea of the order of magnitude.
First you need to know what reference that effective radiated power is relative to. I'm not sure what the FCC convension is on this but lets assume the reference is isotropic. That would mean that the peak power density ove the sphere is 275 times the average power density.
Then we need to consider the radition pattern. In reality it won't be a simplle case of "signal here no signal there" but will gradually decay and without knowing both receiver sensitivity and antenna pattern we can't calculate things accurately. Lets make the unrealistic assumtion that for all directions the antenna either transmits fulll power or nothing. Lets also assume that the sattelite is pointing stright down.
Lets further assume that the footprint is small enough that a section of the earths surface and a section of a sphere surrounding the sattelite can be considered to have the same area. According to wolfram alpha a sphere of radius 625km has a surface area of about 4.9*10^6 square km. so 1/275 of that would be about 17.8 * 10^3 square km
In practice I would expect that this is fairly pessimistic.
Also accoridng to wolfram alpha the surface area of the earth is appoximately 510 * 10^6 square km. So if my assumptions above were correct it would take about 30K satteliates to cover the earth.
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step 1: build company that launches sats.
step 2: build another company that requires launch capability to be cost effective (give it time.)
step 3: build another company that can generate revenue off of capabilities of 1 and 2 -- repeat
Building your own vertical integration; even if all this basically requires government handouts/subsidies -- i'd argue he's doing far more with them than most companies and contractors do.
Sure, try there first. But don't rely on their approval.
The feds are so f'ed up at this point that I don't think you can trust them to be rational on the issue. If they don't respond in a timely manner with a "yes"... ask someone else and launch through them. The feds don't own space. You can launch from a lot of places. Talk to the French, talk to the russians, talk to the chinese, talk to the indians.
Make that part of your ask from the FCC... unofficially make it clear you're going to do it. And the only question is whether the US has a role or not.
Then count to ten and pull the trigger.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
This is a legitimate concern. Is there room in LEO for 4000 more space vehicles? If there is, will SpaceX design them with the capability to remotely de-orbit them safely when they've reached EOL, or are there just going to be 4000 more obstacles hanging around up there to collide with something else?
Another question I have is, do we really need this in the first place?
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
Space is really, *really* fucking big. Even low earth orbit at any given altitude is vast; it's literally larger than the surface of the planet. Add altitude shells to that - go up a few KM and you're now a few KM away from anything in the lower shell, even at closest point of approach - and there's an astonishing amount of room in space.
You wouldn't ask if there's room for 4000 more ships on the ocean, despite the fact that there's a lot less ocean and a lot more things crossing it vs. what we have in LEO. You wouldn't even ask if there's room for 4000 more cars on the road in the continental US, despite there being many orders of magnitude less space on US roads than there is in any given LEO altitude. Satellites, functional or not (including debris), move in predictable patterns, and functional satellites have thrusters that allow them to alter or maintain their course.
Agreed, of course, that the satellites should be capable of de-orbiting. But seriously, this "is there enough space in LEO?!?" meme is kind of dumb, at least right now. Let's assume you put each satellite in the middle of 20x20 KM non-overlapping exclusionary zone (omitting the third dimension for now). 400 KM^2 per bird. 1,600,000 KM^2 total. Sounds big, right? You could fit that entire collection, with a hundred thousand square KM left over, into Alaska. Don't get me wrong, Alaska is a big place, but it's not *that* big on the world scale. That's all in one orbital shell.
There's no place I could be, since I've found Serenity...
And assuming they can make a landing soon, there'll be a lot of high risk re-re-refurbished rockets that they might load up with cheap cubesats and if it works it works, if it doesn't no biggie. If there's no customers, why not make your own market?
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(Damn, I thought it was 250-ish each way, not round trip.)
It's 250-ish round trip to the satellite and back, but comms satellites aren't very interesting to talk to. It's 250-ish each way to the server and back. Around half a second of delay before you can get a response to a message while working over a geosynchronous satellite link.
anyway no one has come close to "trying".
Unfamiliar with Iridium I see. Interestingly SpaceX has the contract to launch the next generation Iridium constellation which this proposal will directly compete with.
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I suppose they know what they're doing, but if the FCC says "no", I think they should consider responding with the finger and a launch.
Well, there is a lot of space up there. ~1,292,613,096,000 km^3