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Can We Get Global Broadband From Low-Earth Orbit Satellites? (blogspot.com)
"The internet is unavailable to and/or unaffordable by about 50% of the world population," writes Larry Press (formerly of IBM), who's now an information systems professor at California State University. But he's also long-time Slashdot reader lpress, and reports on new efforts to bring cheap high-speed internet to the entire world.
SpaceX, Boeing, OneWeb, Telesat, and Leosat are investing in very large projects to deliver global, high-speed Internet service [using low-earth orbit satellites]. This could be a significant option for developing nations, rural areas of developed nations, long-haul links, Internet of things, and more by the mid-2020s.
Parts of Alaska could see internet-via-satellite as soon as 2020, according to Larry's article, which adds that the technology could even be used to bring high-speed internet access to ships at sea.
Parts of Alaska could see internet-via-satellite as soon as 2020, according to Larry's article, which adds that the technology could even be used to bring high-speed internet access to ships at sea.
We already get internet by satellite from a dozen companies.
Here are the top ten.
http://www.toptenreviews.com/s...
Latency is the problem with satellite packet networks.
For varying definitions of broadband. How easy is it to overload a cell network? Each satellite is equivalent to one tower serving everyone under it. One tower for all of Chicago... Would it work as a contiguous network worldwide? Sure. Would it have enough throughput to be called broadband for a significant percentage of the world? I doubt it. Even given incredibly wide bands to operate over the number of customers under it is equally large.
Covering the globe with internet via low earth orbit would take a LOT of satellites, or you could use just three. Like these folks are planning. https://www.viasat.com/product...
That depends... Light is measurably slower in glass, so the route via satellites can be potentially faster.
Ezekiel 23:20
Hasn't Alaska suffered enough?
The latency of low Earth orbit satellites is only around 2% of the latency of geosynchronous orbits and probably less than twice that of a terrestrial connection. In fact if the LEO satellite is right overhead it's probably less than 500 miles from you which probably gives a similar latency to terrestrial connections.
And they fall out of orbit and have to be replaced too often. Bad for the environment!
See Teledesic
Getting a two-way connection from a moving satellite is a nightmare. You get all kinds of frequency-shift, Doppler, atmospheric, and localized multi-path problems. You'll need a big chunk of spectrum for all the error correction and sync signals required. You'll either need a tracking dish, which will be expensive, or a phase-array, which is cheaper to build but will require a more complicated and expensive front-end.
It may work for niche cases for low-bandwidth applications in remote areas. I'm guessing the uplink hardware will be so expensive that you'll have micro-ISPs serving small areas.
My Other Computer Is A Data General Nova III.
Who expects a 2020 wireless system to be no better than a 2005 wireless system?
It would take a lot of LEO satellites, but it would also offer *massively* greater capability than using just 3 GEO sats.
Ezekiel 23:20
Covering the globe with internet via low earth orbit would take a LOT of satellites, or you could use just three. Like these folks are planning. https://www.viasat.com/product...
If they are geostationary, they won't have low latency because too far away. If they are leo then they will be moving and three won't be enough to cover everything, so how can 3 sats work?
LEO Satellites at 1200 miles up will have a minimum Earth-Ground latency of 24 milliseconds and Earth-Ground-Earth Latency of 48 milliseconds because of the speed of light ---- this is a major latency issue unless there are MANY infrastructure Earth stations at major colocation facilities AND the traffic can be efficiently routed, so we're not landing traffic in a NEW YORK internet exchange that then needs to be routed to SAN FRANCISCO, or Atlanta, and thus appending another 50 milliseconds of ground latency after the satellite hop, for example.
I used to do tech support for an ISP, and I had to deal with issues like this every day. Just to get a response from your ISP's router, your packet has to go up to orbit and back. Twice. That can add quite a bit to your response time. However, given the choice between that and no connection at all, it's something that can be lived with.
Good, inexpensive web hosting
Well, at least the ground-based 2005 wireless systems we have can survive common X-Class Solar flares and normal-magnitude CMEs we occassionally see without risk of equipment being permanently destroyed .
Of course, right overhead is a rare optimistic case. Worst case would be satellite on horizon, there your round trip would be at least 130 ms (assuming at least 300 km orbit). By satellite standards pretty good and serviceable for most non-gaming situations.
Adding solar UAVs to the mix may confer a lot of the benefits of geosyncronous satellites, though would require a ton more of them.
XML is like violence. If it doesn't solve the problem, use more.
Of course *all* satellite communication is at the speed of light, whether optical or not.
XML is like violence. If it doesn't solve the problem, use more.
Being somewhat familiar with SpaceX's plans here are a few advantages of their approach, I guess compared to traditional satellite providers:
They're planning to deploy thousands of cheap, small, short-lived satellites in LEO, which means:
-They get the advantages of cheaper production due to economies of scale, orders of magnitude better than something like GPS or Iridium.
-So many units means they can just over-provision, use less hardened, cheaper components, and just replace units as they fail.
-Being in LEO means they have a shorter lifespan due to atmospheric drag, so they stay up for maybe 5 years, drop into the atmosphere and are replaced by newer, better hardware.
-I did a back of the envelope calculation once and I think I came up with something like 1/3 the latency of fiber when going halfway around the earth, due speed of light in glass vs air/vacuum, and the various geographical features cables need to contend with.
-One of the reasons I remember being mentioned for SpaceX getting into building their own satellites when their rocket reuse program was just getting off the ground is they'll eventually end up with a supply of rockets that's larger than the entire launch market is going to need, at least in the short term, so this is a way for them to be their own customer and amortize the cost of the rocket by reflying it 10 times with cargo they can afford to lose.
I would mod you up if I had any mod points. The current systems available on cruise ships have decent speed but terrible latency. A lower orbit could help but you are still stuck with a long distance between the satellite and land/ocean. Lower cost would help travelers on land and sea even if there is no good cure for latency. We have friends who use satellite ISP at home as well on the road and additional choices would be welcome.
Embrace the future.
No it's not - the round trip to low earth orbit at the speed of light is less than 1ms, and the fact that signals travel in a vacuum between sats (rather than in glass or copper along the ground) means that at any distance between end points over 400 miles, latency is LOWER via LEO than via ground signalling systems.
You're thinking of geosynchronous based systems.
Once you get over 50 miles from the destination host going via the satellite would be faster even if you assumed no switching systems in between.
On the ground - 50 miles of electrical signal in copper = 1.25ms
Via space - 84 miles up, 84 miles down, 51 miles through space = 1.25ms
Even if you assume glass fibre all the way, it's still faster by LEO for any time the distance exceeds 400 miles.
Yes, but those 3 geostationary sats would have enormous issues with capacity and latency.
Ya, this sounds exactly like what Iridium was originally supposed to be. Except it ended up costing around $6 billion to make the Iridium network and the company went bankrupt. The company ended up getting sold for $33 million and even at that price service is expensive (they have had to replace satellites and they are launching a second generation system). Iridium was changed to being used for satellite phones and can only handle short bursts of 2K of data.
https://en.wikipedia.org/wiki/...
The others on your list I believe use geostationary orbits so they are high latency.
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That depends... Light is measurably slower in glass, so the route via satellites can be potentially faster.
In theory yes, light in a fiber optic cable travels at about 2/3rds of c so halfway around the world would be 20015 km (6371 km* pi) and take 100 ms (20015 km / (2/3 * c)). Bouncing it up to a satellite flying at 800 km, between LEO satellites and then 800 km down again would be 2*800 km + (800+6,371) km * pi = 24128 km and take 80.5 ms at c. Whether it would be practically feasible I'm not sure as decoding/repeating a wireless signal will probably cost that and more.
But it's more useful to cap the penalty, assume the uplink is like right next to the ground station, you could hook up to the same fiber optic cable they do. Instead you get a 2*800km round trip at c = 5.34 ms + a bit of processing. If we say no worse than a 10 ms penalty that's the same penalty as being 2000 km further away. It's less than accessing an east coast server from the west coast or vice versa. Unless you're into high end eSports or high frequency trading that's quite negligible.
Live today, because you never know what tomorrow brings
Just go direct. Network over neutrinos!
I wouldn't be surprised if some high-frequency traders have actually hired scientists to study if this is feasible. I hope the 'no' cost a lot of money to establish.
Places free of the pollution of the internet are getting rarer by the day. Digital quiet is a disappearing resource. What about VLA and people who prefer to live and vacation in places without connections?
putting the 'B' in LGBTQ+
The problem is not whether it can be done, weâ(TM)ve done it already. The problem as always is cost.
Pretty much all of inhabited areas these days has been wired with data-capable systems, even if itâ(TM)s just 56k or DSL for third world countries with a twisted pair. Most areas have wireless coverage of some sort. Whether or not the locals can or want to afford the connection is another thing.
Putting stuff in LEO or space doesnâ(TM)t solve that problem of either bandwidth or cost, actually it makes the equation worse.
Custom electronics and digital signage for your business: www.evcircuits.com
Do the math. First make an estimate of how much solar power your 300 (or whatever number of) satellites can catch. Then multiply that by the conversion to RF power and spread the resulting power evenly over the surface of the earth. You now have power density. Next, calculate the maximum antenna size/directivity a single user can use. His beamwidth can't be narrower than the inter-satellite angular spacing. Next after derating the above result based on necessary link margin for foliage, precipitation loss (if it applies at the wavelength used) etc, apply Shannon's equation to this power budget and calculate the available per-user information rate. Finally ask yourself who besides the fringe will be willing to pay enough for this relatively low average rate to support the whole thing. As with the Iridium system, even without latency and particularly in the present age with the per-user bar up in the 10's of Mbps, the overall user base will not be willing to pay so much for so little. For a few users the few kbps (not Mbps) average rate might be useful but it is necessary to have a lot of users to pay for it all. This is essentially a very over-subscribed approach and the physics, even with moderately good nearly line-of-sight radio paths, won't support any reasonable economic model. The US 7B original cost of Iridium turned into something only a few tenths of a percent of that at the last sale, as I understand it. Yes, it is possible to make a system that can support a few users at high rates or a lot of users at low average rates but the economics require both simultaneously. It's not going to happen with a LEO satellite system in this day and age.
Nothing more to add.
And that's just the connection to the satellite. Then it turns out the server farm where the game is running is in the OPPOSITE direction.
-=This sig has nothing to do with my comment. Move along now=-
I am surprised to see corporations investing on poor countries. What kind of return on investment do they expect here?
You should probably try reading again.
Of course, right overhead is a rare optimistic case. Worst case would be satellite on horizon, there your round trip would be at least 130 ms (assuming at least 300 km orbit). By satellite standards pretty good and serviceable for most non-gaming situations.
The idea is to use a large constellation of small, relatively cheap mini/micro-sats in a very low orbit, possibly as low as 120-150 miles/200-250 km that are economical enough between satellite cost and launch costs that they can be regularly replaced as their orbits decay.
With that design a single ground station would 'see' at least 3 or more sats at any given time. Shorter distance also means lower transmitter power required from the device on the ground, *and* in the sat, making it smaller/cheaper as well. At just a couple hundred km and with multiple signal paths available to prevent lost/dropped packets, etc, on top of that, suddenly it starts to become a much more viable-seeming arrangement for a lot more people.
Sure, it's not going to equal a fiber connection or even regular cable broadband, but it could be one possible solution to providing ad-supported/free and/or low-cost/subsidized internet for those who currently cannot afford it or who have few or no other alternatives for whatever reason (geography, etc).
Strat
Progressivism (aka US 'Liberalism'): Ideas so good they need a police/surveillance-state to enforce.
It has been estimated that the earth is naturally bombarded by 37000-78000 _tons_ of meteorites a year. a few hundreds/thousands of sats will not make a noticeable difference.
http://curious.astro.cornell.e...
Democracy is a sheep and two wolves deciding what to have for lunch. Freedom is a well armed sheep contesting the issue
I know more than a few people that do like to disconnect even if their job requires them to be connected at all times.
These are the ones that like to leave their phone on, even if they're off-duty, and don't answer calls or "decline" them so as to give the illusion that they couldn't reach the ringing phone in time before it goes to voicemail.
Being in a place where there's no signal and/or having a device that is "not reachable at this time" means a lot to these folks.
Once companies hear about practical, cost-effective satellite internet and buy devices for their employees that can use this internet, employees will have very little excuse to say "Sorry, I was in a spot with no signal."
Some people may be very uncomfortable with this concept.
..web..
Seriously..how about we deal with what we have before asking for seconds .. (i'll wager 50% is a suspect figure)..
Bitch you KNOW the side.. WORLD MAFUCKIN WIDE..
ever tried to point a dish at a low earth orbit satellite?
"Anything plus internet is a winning combination" said every pets.com investor...
Ken
Bouncing it up to a satellite flying at 800 km, between LEO satellites and then 800 km down again would be 2*800 km + (800+6,371) km * pi = 24128 km
I'm pretty sure that is slightly pessimistic. The first and last hops can be diagonal, and the hops between the satellites are going to be linear.
Whether it would be practically feasible I'm not sure as decoding/repeating a wireless signal will probably cost that and more.
There's going to be delays, but I'm quite certain the fiber optic signal doesn't go from Europe to Australia in one hop either.
Ezekiel 23:20
Is this supposed to be funny or real?
"There should be the same amount of atmosphere to cross whether the Sun rises due East in the summer, or South-East in the winter."
Get a globe and check it out, you will find that this statement is not true.
"Space is fake. The Earth is flat. The eclipses prove it."
Hardly. The Earth reflects light back to the moon, hence you can see the back of the moon (both at a new moon and at a solar eclipse). The Earth is not translucent, so the lunar eclipse is pretty dark (but not completely, due to the atmosphere).
The fact that you cannot imagine a round Earth does not mean that it has to be flat. :-)
"The internet has already grown to be available to and affordable by about 50% of the world population," writes Larry Press (formerly of IBM), who's now an information systems professor at California State University.
FTFY.
There's no time like the present. Well, the past used to be.
I suspect that SpaceX will somehow find a way to use excess launch capacity on customer launches to squeeze in a few free LEO internet sats for themselves. (Having said that, I have no idea if that's physically possible with the different orbits that customers need vs what they need.)
Clearly your not on a properly designed wireless network. We run one here in Florida. I have both a Comcast connection and one of our wireless connection at my house. The Comcast connection will do 12 down a 2 up. The wireless connection does over 20 down and 8 up. Latencies are better to most sites on the Internet too by about 15ms. We have hundreds of satisfied customers (seriously, about the only time we lose one is if they move out of our coverage area).
no one wants satellite internet