Will Exede/ViaSat ever launch into Low Orbit

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I know that most sattilites are launched into higher orbit. But why don't more companies launch into lower orbit? This would greatly reduce costs of the launch. While at the same time would greatly lower latency to around 150ms-200ms ping. To me it sounds like a win win. Any ideas?
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Cigr Nation

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Posted 2 years ago

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Gregory Davis

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Low orbit is not an option - the satelite would need to be orbiting the earth continuously - i.e. not be geostationary and thus not cover the same part of our planet continuously.  Geostationary means HIGH orbit and thus remains over the same part of our planet.  Note that our GPS satelites are in LOW orbit - but there are several constantly rotating about our planet.  I've read stories about some big companies looking into launching several LOW orbit sateilites to bring WiFi to the masses - still several years away that's if they decide to do so.  Sorry about my spelling errors.  Low orbit would only slightly improve your PING response, our to and from satelite transmission are VERY FAST.  It's how BUSY the satellite computers and corresponding ground stations that add to the delay.
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Alex, Viasat Corporate Communications

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One more note here from the economic point of view. If you're a company like us that's in the business of selling bandwidth, you're going to want to maximize the return on the investment on the machine (in this case a satellite) you built to manufacture that bandwidth. LEO satellites spend the bulk of their time over water, deserts and other places where there are no people to buy your bandwidth. With a GEO satellite, you can point your beams where the subscribers are and maximize your investment. You make the decision to live with the latency issue, which isn't as big a deal as it's made out to be anyway, and you get a more efficient bandwidth-manufacturing machine!
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J S

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I'm a software engineer and high latency has never been a issue for me for the programs that I write. What we need is higher data caps and satellite capacity. 

If exede is ever able to create mobile dishes perhaps the size of a laptop it will be a game changer for humanity. People will be able to bypass internet controls imposed by dictatorships.
(Edited)
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Gregory Davis

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I too am a software engineer (retired) and have been tasked with syncing (via time) aircraft data with radar/range data.  The radar range data was delivered to our facility via microwave and roughly 0.5 seconds behind, in time, from our aricraft data.  Our customers wanted some of the aircraft data "in sync" with the radar/range data.
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Nathan Williams

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Speak for yourselves, but latency is quite important to me. If there was a lower latency option available I'd already be gone, but tethering to 4g networks has abysmal performance on all measures. As soon as a company offers something workable I'm outta here. Even if it's more expensive and barely lets me stream Netflix.
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Nathan Williams

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People around here are so fed up with lack of options that we're working through the county government to try and fund a fiber line supporting a WISP tower network.
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xode0000, Champion

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More precisely: circular orbits around the earth work like this:



    ...where v is the speed at which the satellite moves in its orbit; G is Newton's gravitational constant (about 6.67 * 10^-11); M is the mass of the earth (about 5.975 * 10^24 kilograms); and r is the distance from the satellite to the center of the earth.

Geostationary orbit is an orbit where the satellite's speed is exactly in lock step with the speed of the rotation of the earth's surface around the center of the earth, such that, from the point of view of someone on the surface of the earth, the satellite appears stationary (i.e. doesn't move).  Given the earth's mass and Newton's gravitational constant, geostationary orbit has to be about 22,350 miles above the surface of the earth.

For a satellite in a lower orbit, its speed is going to have to be greater, since r is smaller, meaning that, from the point of view of someone on the surface of the earth, the satellite is constantly advancing towards the east.  This in turn means that:
  1. there would have to be more than one satellite so that at least one satellite is visible from any point on the earth at all times;
  2. the ground antennas (i.e. a customer's installation and the gateway on the other end of the satellite link from the customer's installation) would have to constantly move in order to track the satellite, since internet service requires that data be able to go to the satellite as well as come from the satellite and the antenna has to be focused on the satellite due to its distance;
  3. the ground antennas would have to flip from that satellite to the next one when that satellite went below the horizon.
In other words, maintaining the satellite link for satellites in low earth orbit is going to be much more complicated than for a satellite in geostationary orbit.  It would be much like maintaining a cellphone network on steroids.  However, given how fast technology has been advancing, it could happen.  Regarding launch costs, most of those costs, and the energy involved, are just to get the satellite from the ground and into low earth orbit.  Getting the satellite from low earth orbit into geostationary orbit is not all that much more expensive.

Regarding ping, the geostationary satellite link really is most of the ping time, due to how far away that satellite is.  The speed of light in a vacuum is 299,792,458 meters per second.  A ping requires four 22,350 mile trips to the satellite: 1 up and 1 back to get the ping request from you to the ping server and 1 up and 1 back to get the response back to you from the ping server.  The total time to make those 4 trips works out to about 0.48 seconds.  For satellites in low earth orbit about 1000 miles up, the satellite link time would be about 22 times less, or a little more than 0.02 seconds.  However, even a 0.5 or 0.6 second ping time is plenty workable, since almost all of the internet works just fine with it.  Given that, anything can be made to work with a 0.5 or 0.6 second ping time; if something doesn't work with that ping time it is because whoever designed that thing doesn't want to do what it takes to make their thing work with that ping time.