Starlink Beta Test

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Paratus

Lifer
Jun 4, 2004
17,437
15,352
146
This is light based and not radio wave based?

I know waves are waves are radio waves like 1/100th the speed maybe 1/1000th the speed?
Ah I was under the impression waves for broadcast were in the 500-1000 miles per hours type thing (maybe minute). I thought the super high fast spectrum stuff needed too much power/antenna to be practical.
Thank you for the education.
So here’s the basics on satellite internet and what makes SpaceX different along with some physics 101 (feel free to ignore if you know this stuff already)

Satellite internet, like Hughesnet, TV like Direct TV, and Radio like Sirius XM all use a small constellation of large satellites in Geostationary/Geosynchronous orbit.

These orbits are unique in that satellites placed there rotate at the same rate the ground does. So geostationary satellites are always over the same point on the equator. The speed it takes to be at that altitude takes 24 hours to travel one complete circular orbit.

1597544768523.gif

The benefit to this is anyone on the ground who can see the satellite and wants to communicate with the it just needs to point a dish at one point in the sky. From geostationary orbit you can see about 1/3 of the planet.

The downsides are first that to be in geostationary orbit you have to be at 22,300 miles above the Earth. As @repoman0 said all electromagnetic waves travel at the speed of light in a vacuum.
EMSpectrumcolor.jpg

(All of these waves are made of photons and travel at the speed of light. The speed of light is fastest in a vacuum and slower in other mediums)
1597546680129.jpeg

So @ the speed of light in a vacuum of 186,000 miles per second it takes light a round trip time of 240 milliseconds. That‘s the minimum extra latency added to the other latencies of connecting to the internet. No twitch shooters for those on satellite internet.

Second, those orbits are highly desired and can’t accommodate a large number of satellites. So your 10,000s of customers are sharing bandwidth on just a few satellites.

Finally those satellites are meant to last decades and are very expensive to build and launch. In fact for most of the last several decades it cost more than. $10,000/pound to launch to geostationary orbit.

What SpaceX is doing is leveraging their unique expertise to provide satellite internet comparable to cable and cellular in latency and bandwidth.

To do this they have to lower the altitude of their satellites low earth orbit of about 340 miles. Just a bit above where the ISS operates. This lowers the up/down latency to only 3.65ms plus the other ground latencies to connect to the internet.

The problem is satellites at that altitude orbit the earth in 90-100 minutes. So you won’t be able to point at a single satellite. Ground user will need to continually hand off from one Starlink satellite to another. Plus at that altitude you can only see a much smaller portion of the Earth. To view more users and maintain a connection SpaceX needs a lot more satellites.

Now if it was going to cost $10,000/ pound this would be financially impossible. Iridium satellite phones tried this on a smaller scale in the 90’s and went bankrupt. SpaceX however has drastically lowered the cost to launch LEO and these satellites can be smaller and lighter because they are closer to Earth. In fact SpaceX has fit 60 in a single launch.
90


Also being in LEO means they will eventually spiral in and burn up in a few years so they don’t have to be built to last as long as geostationary satellites further reducing costs.

Finally with all those satellites (they are approved for 12,000 satellites if I recall) users won’t be sharing as much bandwidth.

It should be possible for SpaceX to provide bandwidth and latencies comparable to average suburban internet for comparable costs.
 
Feb 4, 2009
35,851
17,382
136
So here’s the basics on satellite internet and what makes SpaceX different along with some physics 101 (feel free to ignore if you know this stuff already)

Satellite internet, like Hughesnet, TV like Direct TV, and Radio like Sirius XM all use a small constellation of large satellites in Geostationary/Geosynchronous orbit.

These orbits are unique in that satellites placed there rotate at the same rate the ground does. So geostationary satellites are always over the same point on the equator. The speed it takes to be at that altitude takes 24 hours to travel one complete circular orbit.

View attachment 28082

The benefit to this is anyone on the ground who can see the satellite and wants to communicate with the it just needs to point a dish at one point in the sky. From geostationary orbit you can see about 1/3 of the planet.

The downsides are first that to be in geostationary orbit you have to be at 22,300 miles above the Earth. As @repoman0 said all electromagnetic waves travel at the speed of light in a vacuum.
EMSpectrumcolor.jpg

(All of these waves are made of photons and travel at the speed of light. The speed of light is fastest in a vacuum and slower in other mediums)
View attachment 28083

So @ the speed of light in a vacuum of 186,000 miles per second it takes light a round trip time of 240 milliseconds. That‘s the minimum extra latency added to the other latencies of connecting to the internet. No twitch shooters for those on satellite internet.

Second, those orbits are highly desired and can’t accommodate a large number of satellites. So your 10,000s of customers are sharing bandwidth on just a few satellites.

Finally those satellites are meant to last decades and are very expensive to build and launch. In fact for most of the last several decades it cost more than. $10,000/pound to launch to geostationary orbit.

What SpaceX is doing is leveraging their unique expertise to provide satellite internet comparable to cable and cellular in latency and bandwidth.

To do this they have to lower the altitude of their satellites low earth orbit of about 340 miles. Just a bit above where the ISS operates. This lowers the up/down latency to only 3.65ms plus the other ground latencies to connect to the internet.

The problem is satellites at that altitude orbit the earth in 90-100 minutes. So you won’t be able to point at a single satellite. Ground user will need to continually hand off from one Starlink satellite to another. Plus at that altitude you can only see a much smaller portion of the Earth. To view more users and maintain a connection SpaceX needs a lot more satellites.

Now if it was going to cost $10,000/ pound this would be financially impossible. Iridium satellite phones tried this on a smaller scale in the 90’s and went bankrupt. SpaceX however has drastically lowered the cost to launch LEO and these satellites can be smaller and lighter because they are closer to Earth. In fact SpaceX has fit 60 in a single launch.
90


Also being in LEO means they will eventually spiral in and burn up in a few years so they don’t have to be built to last as long as geostationary satellites further reducing costs.

Finally with all those satellites (they are approved for 12,000 satellites if I recall) users won’t be sharing as much bandwidth.

It should be possible for SpaceX to provide bandwidth and latencies comparable to average suburban internet for comparable costs.

Excellent breakdown thank you
 

Spacehead

Lifer
Jun 2, 2002
13,067
9,858
136
To do this they have to lower the altitude of their satellites low earth orbit of about 340 miles. Just a bit above where the ISS operates. This lowers the up/down latency to only 3.65ms plus the other ground latencies to connect to the internet.

The problem is satellites at that altitude orbit the earth in 90-100 minutes. So you won’t be able to point at a single satellite. Ground user will need to continually hand off from one Starlink satellite to another. Plus at that altitude you can only see a much smaller portion of the Earth. To view more users and maintain a connection SpaceX needs a lot more satellites.
So, can a stationary dish continuously pick up a signal from a moving satellite or will it need to be continuously moving to track it & each successive hand-off satellite?
 

BarkingGhostar

Diamond Member
Nov 20, 2009
8,410
1,617
136
Those latencies are not suitable for video, voice or even gaming. So, you are marketing to whom? The bandwidth is insufficient for long-range medical use ( a la video surgeries) but the only application I can think of is non-real time services like email, file download. Jesus, can you imagine the percentage of retransmissions.
 
Feb 4, 2009
35,851
17,382
136
Those latencies are not suitable for video, voice or even gaming. So, you are marketing to whom? The bandwidth is insufficient for long-range medical use ( a la video surgeries) but the only application I can think of is non-real time services like email, file download. Jesus, can you imagine the percentage of retransmissions.

I disagree 30 to 40 ping is very comparable to wired solutions and the 75 outlier is still good enough
 

ponyo

Lifer
Feb 14, 2002
19,688
2,810
126
Those latencies are not suitable for video, voice or even gaming. So, you are marketing to whom? The bandwidth is insufficient for long-range medical use ( a la video surgeries) but the only application I can think of is non-real time services like email, file download. Jesus, can you imagine the percentage of retransmissions.
Damn, you work for AT&T and can't see who this would appeal to or the vast market potential of Starlink? And you always complain about the clueless top management...
 

[DHT]Osiris

Lifer
Dec 15, 2015
16,789
15,804
146
Those latencies are not suitable for video, voice or even gaming. So, you are marketing to whom? The bandwidth is insufficient for long-range medical use ( a la video surgeries) but the only application I can think of is non-real time services like email, file download. Jesus, can you imagine the percentage of retransmissions.
As the two above me said, 30-70ms latency is fine for basically all applications, aside from the outlier with twitch shooters. The bandwidth is fine for medical use? Not even sure what that is supposed to mean. Who builds internet specifically for video surgeries?

This would be suitable as-is for 99% of users, and I expect it to get better over time.
 

Paratus

Lifer
Jun 4, 2004
17,437
15,352
146
So, can a stationary dish continuously pick up a signal from a moving satellite or will it need to be continuously moving to track it & each successive hand-off satellite?
That’s a good question. It’s one of the challenges SpaceX engineers would have had to overcome. Last I looked into it a couple of months ago they hadn’t released details on the ground stations.

It seems possible with enough satellites a second satellite would pass through the point in the sky your dish “sees”’before the first one leaves without having to move your dish.

With what looks like real results in the OP the answer is probably out there now.
 

Red Squirrel

No Lifer
May 24, 2003
69,825
13,398
126
www.anyf.ca
I think it will use beam steering, kinda like 5G. But the dish also has to mechanically adjust itself, just not sure how often it will be doing that, if it's like an initial setup thing, or if it will actually continuously be locking in to a satellite. From my understanding there will always be at least two active satellites so it will hand over. Satellites will be doing the same kind of hand over to each other as well as they will act as a mesh.

Come to think of it I wonder how many internet base stations connecting to rest of internet there will be, if it will only be in the states or if they will put them around the world. That will greatly affect latency for international users as say there is only a base station in the states and you are in Europe and go to access a server that's hosted locally, technically your connection would go to the states via starlink, then come back via fibre. I wonder if they will even have a program where people can setup their own base stations. Say you have access to lot of bandwidth you could basically volunteer some. That would actually be cool if they did that. I guess most ISPs would frown upon that though.
 

Spacehead

Lifer
Jun 2, 2002
13,067
9,858
136
@Red Squirrel
/\
Am i reading you wrong, wouldn't you need your own base station for this to work? What's the point of having satellite internet if the feed has to pass thru your crappy lines anyway which is the whole point of getting satellite in the first place?
 

Red Squirrel

No Lifer
May 24, 2003
69,825
13,398
126
www.anyf.ca
@Red Squirrel
/\
Am i reading you wrong, wouldn't you need your own base station for this to work? What's the point of having satellite internet if the feed has to pass thru your crappy lines anyway which is the whole point of getting satellite in the first place?

By base station here I'm talking about where the starlink network accesses the internet. Ex: as a customer when you connect to it, and access a website, it needs a way to access the normal terrestial internet where that website is hosted. So I am curious how they have that setup, if there's only one base station or if they have many or if they may even at some point allow people to essentially become a bandwidth provider if they have access to lot of bandwidth.
 

Midwayman

Diamond Member
Jan 28, 2000
5,723
325
126
Those latencies are not suitable for video, voice or even gaming. So, you are marketing to whom? The bandwidth is insufficient for long-range medical use ( a la video surgeries) but the only application I can think of is non-real time services like email, file download. Jesus, can you imagine the percentage of retransmissions.

The real client is financial markets. The latency between new york and london is lower via this than fiber. The advantage only rises the further you go. I have serious doubts about this replacing internet for the average joe. Any wireless solution runs into a hard wall of a bandwidth problem pretty quick.
 

Fritzo

Lifer
Jan 3, 2001
41,920
2,161
126
As an astronomy geek, I'm a little miffed about his whole Starlink thing- they littered the globe with these satellites and there going to seriously interfere with deep space observations :mad:
 

repoman0

Diamond Member
Jun 17, 2010
5,143
4,466
136
As an astronomy geek, I'm a little miffed about his whole Starlink thing- they littered the globe with these satellites and there going to seriously interfere with deep space observations :mad:

Douchebag billionaires polluted pretty much the entire planet for profit, why not the night sky too
 

Fritzo

Lifer
Jan 3, 2001
41,920
2,161
126
Douchebag billionaires polluted pretty much the entire planet for profit, why not the night sky too
Here's an example of what Starlink is doing to extended exposures:

1597689198548.png

Those dotted lines are all Starlink sats.
 

Spacehead

Lifer
Jun 2, 2002
13,067
9,858
136
I have serious doubts about this replacing internet for the average joe. Any wireless solution runs into a hard wall of a bandwidth problem pretty quick.
As was already mentioned, it's not a solution for people that already have decent access to the internet. It's for those of us that have few options & for areas with no options yet. It's supposed to be global.

As an astronomy geek, I'm a little miffed about his whole Starlink thing- they littered the globe with these satellites and there going to seriously interfere with deep space observations :mad:
12,000 approved Starlink satellites(30,000 potential), not sure how many are up at one time. Another 3,000 planned at least by Amazon. Who knows who else is planning anything.
 

BarkingGhostar

Diamond Member
Nov 20, 2009
8,410
1,617
136
Sorry, guys, I must be spoiled. I'm use to 4 ms ping times on my personal Internet service, and AT&T's mobility requirement for call setup is <10 ms. In fact I think the call setup requirement is now 4ms from handset to mobility switching center. As such, I was comparing latencies where I've seen it impacted on networks, especially considering the congestive nature. It takes one remote pornhubbian to make the entire unlit valley miserable. AT&T is clueless in a lot of things. But it is also known that they wish to not be in the a) landline telephone business, b) in the consumer ISP business, and c) not do business with any small businesses (T3 and above is their thing).
 

Red Squirrel

No Lifer
May 24, 2003
69,825
13,398
126
www.anyf.ca
As an astronomy geek, I'm a little miffed about his whole Starlink thing- they littered the globe with these satellites and there going to seriously interfere with deep space observations :mad:

They are suppose to address this, hopefully they do. Otherwise any long exposure of the night sky is going to look like graph paper.
 
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Ken g6

Programming Moderator, Elite Member
Moderator
Dec 11, 1999
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They are suppose to address this, hopefully they do. Otherwise any long exposure of the night sky is going to look like graph paper.
Honestly, I think that will happen one way or another at this point. If it isn't SpaceX it will be Amazon's 12,000-satellite constellation. If it isn't Amazon it will be someone else.
 

Red Squirrel

No Lifer
May 24, 2003
69,825
13,398
126
www.anyf.ca
Yeah if everyone is going to be getting in the game it will be quite crowded up there.

I think it's cool seeing the odd satellite but if some of these companies plain don't care and we see them all it will be pretty crazy. I even wonder if it could have some weird effect on wildlife that we don't realize. Like some nocturnal species might actually use the stars to some degree, now suddenly half of them will be moving and it might throw them way off.
 

[DHT]Osiris

Lifer
Dec 15, 2015
16,789
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146
Yeah if everyone is going to be getting in the game it will be quite crowded up there.

I think it's cool seeing the odd satellite but if some of these companies plain don't care and we see them all it will be pretty crazy. I even wonder if it could have some weird effect on wildlife that we don't realize. Like some nocturnal species might actually use the stars to some degree, now suddenly half of them will be moving and it might throw them way off.
Give it another few years, and McD's will figure out it can create some pattern-recognizable golden arches for the cost of a few hundred million. You think it's a matter of companies caring? Hah.
 

Red Squirrel

No Lifer
May 24, 2003
69,825
13,398
126
www.anyf.ca
Give it another few years, and McD's will figure out it can create some pattern-recognizable golden arches for the cost of a few hundred million. You think it's a matter of companies caring? Hah.

You know that's a scary thought, send out a couple 100 thousand satellites up with mirrors that can quickly tilt back and forth and you got yourself a giant space based DLP projector to beam ads to earth. Heck by having multiple tilt angles and multiplexing the whole thing you could even target ads by region. They would be moving in a criss cross pattern you just reassign the pixels as they move and it's seamless.