Amazon proposes satellite internet system

[Autoist]

There are supposed to be 4 or 5 companies trying to do Leo Internet. If only two survive it will make an impact on what we pay for cellular data. If I can put a small satellite receiver antenna on my car and on my home, both connected to the same account, why do I need more than 1GB of cellular data., especially since I work from home.

If they make this happen it could very well change how cell plans are priced. I hope to see pricing in the cable internet range. Even if it is twice as expensive as cable internet that will be cheaper than having sims from three carriers with unlimited data. 2021 will be an interesting year.

[rk911]

Originally Posted by doc

... We just switched to Dish (and it is not nearly as friendly as Direct was) ...

i’m curious...in what way?

[rk911]

Originally Posted by desuhu

Isn't that always the way it is? Investors in new start-ups that fail end up with nothing and the big shots just keep getting richer.

if the startup fails how does anyone get richer?

[Talloaks]

They went bankrupt and the management team bought the assets and satellites for pennies on the dollar. Us investors got nothing, nada, bupkis. The now-private company's doing better than ever and just launched 75 brand new Satellites.[/QUOTE]

I think the reference was to the statement that the investors funded the initial development of assets and technologies. Subsequently, bankruptcy eliminated the investor's position. Post-bankruptcy, the company principals acquired the assets at a steep discount, and redeployed them in a new profitable venture under their ownership.

[Steve 716]

Maybe I'm missing something reading all of this. If a satellite is in geosynchronous orbit it is about 22,000 miles above the equator. Back in the days of analog satellites minimum separation was 4 degrees and a "television" satellite received and resent 24 video/mono audio channels (transponders). Point to multipoint. There was one uplink site per transponder and an infinite number of downlink sites, depending on where and how large the download spot beam covered. Once a method was invented, additional signals like stereo audio, stock crawls, and other signals could be added per transponder. This is how MTV, the Movie Channel, etc came to be. Still, these additional signals had to be transported to the uplink site for that transponder. Each channel had one uplink. This wasn't a problem for the consumer since he was only concerned with receiving a signal, not transmitting it. In spite of the math sited on this thread the delay from transmission to reception is about three seconds. If you watch a news show with a remote feed, if the feed goes over satellite and back down in both directions and you will see about a three second delay from question to answer.

Next came digital geosynchronous satellites. Same point to multipoint system but more channels, a 2 degree separation between satellites, more efficient use of per channel bandwidth, and higher frequency transmission and reception allowing for smaller satellite antennas. There still is the about three second up and down delay. Remember, this applies to geosynchronous satellites. These satellites are not fixed in position by the way. They move in a lazy 8 pattern that the uplink needs to track. Other than electronics life or collision with space debris, the limiting factor in the life of a satellite is the amount of station keeping fuel it carries. In the analog days, when fuel ran low a satellite would fire its thrusters and boost itself into a higher orbit (on command from the uplink) and a replacement satellite would be launched or moved into the vacated position. I don't know but assume the same applies to digital satellites.

This thread discusses satellites in a lower orbit. In the case of GPS you are receiving signals from three or four satellites and comparing signals to determine location. Which satellites? It depends on where you are and what time of day it is because the satellites are in different orbits. This works easily because you are only receiving signals, not transmitting them. For weather and other satellites not in a fixed position relative to earth, reception is subject to line of site availability with satellites that move in relation to the horizon. Still point to multipoint, but uplinking to a satellite requires positioning to wherever the satellite is and tracking it for lengthy communications. If you have multiple satellites to target, as a satellite internet is described in this thread, you still have to track a satellite to transmit a signal to it. Lots of satellites means lots of choices but if you don't point your transmit antenna at the antenna on a satellite, it isn't going to receive your signal.

It is true that the lower the orbit the faster signals will flow and that would decrease signal delay to something usable. This is where I wonder if I am missing something. If you are going to use the internet via satellite you will need to transmit your data to it. How are you going to do that, what equipment will you need, how are you going to eliminate loss of signal when switching satellites, how are satellites going to pass you off from one to another, and how is each satellite going to handle millions of signals being sent to it from earth? Obviously there will be packet switching and addressing involved, but there still needs to be a handoff to make communications seamless. In my somewhat limited experience, I don't see how this is going to be done efficiently and inexpensively and I surely don't see how it is going to be done with an RV moving from location to location. Any ideas?

[F4Jock]

Wonderful! More space junk so that everyone can post trivia on social media. Just what the world needs!

[docj]

Originally Posted by Steve 716

Still point to multipoint, but uplinking to a satellite requires positioning to wherever the satellite is and tracking it for lengthy communications. If you have multiple satellites to target, as a satellite internet is described in this thread, you still have to track a satellite to transmit a signal to it. Lots of satellites means lots of choices but if you don't point your transmit antenna at the antenna on a satellite, it isn't going to receive your signal.

Good point. I've not seen any of these schemes explain how you're going to transmit back to the satellite without a directional, tracking antenna.

[Tom_M]

Originally Posted by Steve 716

If you are going to use the internet via satellite you will need to transmit your data to it. How are you going to do that, what equipment will you need, how are you going to eliminate loss of signal when switching satellites, how are satellites going to pass you off from one to another, and how is each satellite going to handle millions of signals being sent to it from earth?

It will be similar to cellphones. As you drive through an area you are being passed from one cell tower to another. You are transmitting and receiving without any loss of data.

Iridium satellite service has been in service for several years. It consists of several low orbit satellites. Sat phones do not have a directional antenna.

[Survtech]

Originally Posted by Brecklundin

they can't solve on issue and that's the 25 sec round-trip lag to space and back, more if your info is sent laterally around the "SkyNet".

Bound to happen but physics and the speed of light have the final say on just how much it can doo

Not 25 seconds nor 3 seconds. Light travels at 186,000 miles a second so 2-way to GEO satellites (like for Hughesnet satellite internet and things like DirecTV) is 1/4 of a second (22,300 miles x 2 = 44,600 miles round trip divided by 186,000 miles per second = 250 milliseconds). Add a bit for retransmit processing, etc. and the average latency is 638 ms. Quite fast in relative terms but a snail's pace for internet traffic, which typically has 10-20 milliseconds of latency.

SpaceX Starlink and other proposed LEO internet satellites will be in the 750 mile altitude band. Round trip signal travel times will be on the order of 8 milliseconds (1,500 miles round trip divided by 186,000 miles per second = 0.008 seconds). Estimates for SpaceX Starlink latency are 15-25 milliseconds. https://www.spaceitbridge.com/spacex...wer-faster.htm

[Survtech]

Originally Posted by docj

Good point. I've not seen any of these schemes explain how you're going to transmit back to the satellite without a directional, tracking antenna.

You don't need one. An omnidirectional antenna will work just fine. Again, these satellites will only be 750 miles up. Signal strength is inversely proportional to distance squared. So you would need a much weaker trasmitter signal to reach 750 miles than 22,300 miles (where DirecTV satellites are).

One example: SiriusXM satellites are also at GEO (22,300 miles high) yet the little antenna on car roofs is plenty big enough to receive that signal. Internet Satellite will be at 750 miles. The antenna could be tiny.

Still a problem, though, is that the signals can be blocked by many things: the leaves on trees, the roofs of your building, etc. so the antenna will probably have to be outdoors.

[Boomer]

Originally Posted by docj

Good point. I've not seen any of these schemes explain how you're going to transmit back to the satellite without a directional, tracking antenna.

Not to burst anyone's bubble, but to transmit back to a group of LEO satellites doesn't require a directional antenna with Low Earth Orbit satellites. Currently I am working on project that use the Iridium based satellites for both packetized data and network communication, both bi-directional communication paths. Works great, the antenna is basically 1 1/2" square Ceramic insulator with a notch antenna , nothing fancy, can be made on a 2" round Printed Circuit board.

I believe most people on this thread are talking about communications to geosynchronous satellites, which take either lots of power and/or directional antenna.

Anyway bottom line is no directional antenna needed for LEO birds.

[Tom_M]

Here's an Iridium sat phone:

[christyhicks]

Well, we did have Hughesnet in the past, and checked into it again, to find it's prohibitively expensive. If you hardly ever use the Internet it would be "acceptable", but still pricey...if you use the Internet very much at all, it is by FAR the most expensive service you can choose!

In our area, 30 gb a month is $90 + $10 equipment rental, + taxes, with a two year commitment required. 30 gb is not much at all, and not that WE care but if you have someone who plays online games, Hughesnet will tell you right out that the delay means no acceptable multi-player gaming.

IMHO, Amazon would have to be able to offer unlimited plans with no delays, WAY faster than 25 gb speeds, no weather interference, at competetive rates, to be financially successful.

[Dav L]

Let's not forget that any Latency mostly affects the request and the time to get a response. Streaming media, once initiated is unaffected. So, listening to Pandora or watching Netflix is a good experience even with some latency as long as the content source deals with the latency (doesn't require ackbacks within a small time period).
Internet surfing is compromised.
At the same time 5G rollout has started. Your future phone likely will be using all of these sources and selecting best to use at the moment. The Sat likely will be filling coverage holes that the existing 4G and near future 5G cell systems will have.