271–280 of 469 posts
Earlier quoted context omitted.
I think the average Instagram or TikTok user must be using more than 100GB/month. And if you count YouTube and Netflix, it's probably more than that.
Is resolution going to peak? Like speeding on a highway are there diminishing returns? On the other hand, bandwidth availability seems to also drive demand...
not for awhile. apple vision / oculus will stream (4k/8k) 3d movies.
So that is "432 Mbit/s per laser, and 9000 lasers total". I don't know you guys but I find that statement much more relatable than "42 PB/day". Interestingly, they also say each laser "can sustain a 100Gbps connection per link" (although another part of the article even claims 200 Gbit/s). That means each laser is grossly underused on average, at 0.432% of its maximum capacity. Which makes sense since 100 Gbit/s is p…
Data might get counted multiple times as it takes many laser hops to reach its destination.
Earlier quoted context omitted.
I think the average Instagram or TikTok user must be using more than 100GB/month. And if you count YouTube and Netflix, it's probably more than that.
Is resolution going to peak? Like speeding on a highway are there diminishing returns? On the other hand, bandwidth availability seems to also drive demand...
There's of course a limit. The "native" bitrate equivalent of your retina isn't infinite.
Next step though is going to be lightfield displays (each "pixel" is actually a tiny display with a lens that produces "real" 3D images) and I assume that will be a thing, we shall see if it does better than the last generation of 3D TVs/movies/etc. That's a big bump in bitrate.
There's also bitrate for things like game/general computing screen streaming where you need lots of overhead to make the latency work, you can't buffer several seconds of that.
The next gen sci-fi of more integrated sensory experiences is certainly going to be a thing eventually too. Who knows how much information that will need.
When more bandwidth becomes available, new things become possible, sometimes that are hard to imagine before somebody gets bored and tries to figure it out.
When I'm futzing around with ML models, I'm loading tens of gigabytes from disk into memory. Eventually something like that and things orders of magnitude larger will probably be streamed over the network like nothing. PCIe 4.0 x16 is, what 32 GBps? Why not that over a network link for every device in the house in 10 years?
Earlier quoted context omitted.
Laser links are not using phased array antennas. It's a physically moving "turret" with a laser and another with a receiver. And they need to be separate units, because the speeds and distances involved are long enough that you are not receiving from the same direction as you are sending.
> that you are not receiving from the same direction as you are sending It's a thrill to think about that. Starlink is really out there. I bet this is lost on a lot of people. Not to patronize anyone, but what Tuna-Fish is pointing out is that due to the speed of light, the distance between satellites and their relatives velocities, when one satellite is beaming data to another satellite it must aim where the receivi…
Assuming the lenses are about 2 inches across (from photos) and they are 1310nm IR lasers:
https://www.wolframalpha.com/input?i=single+slit+diffraction...
So we have a minimum beam width of 0.0014 degrees.
And the speed of light round trip distance is say 3.3 milliseconds.
So the question is, does the angle between the satellites change faster than 0.0014/0.0033 = 0.42 degrees/second?
Well the worst case is one satellite heading north at 7.4 Km/s and another heading south at 7.4 km/s. Lets assume the satellites are 550 km apart (the distance between planes at the equator), and use the small angle approximation... Comes out as 1.4 degrees per second.
So yes, these satellites do need the ability to aim transmit and receive in different directions! (although they might be able to just defocus the beam a little when angles are changing fast to trade off throughput for design complexity)
So that is "432 Mbit/s per laser, and 9000 lasers total". I don't know you guys but I find that statement much more relatable than "42 PB/day". Interestingly, they also say each laser "can sustain a 100Gbps connection per link" (although another part of the article even claims 200 Gbit/s). That means each laser is grossly underused on average, at 0.432% of its maximum capacity. Which makes sense since 100 Gbit/s is p…
>these laser links are used in bursts and the link stays established only for a few tens of seconds or minutes, until the satellites move away The way Starlink satellites are in orbit, the same satellites will remain "ahead" and "behind" you in the orbital plane. Those laser links (specifically!) will remain relatively persistent. This arrangement is similar to Iridium FYI. FTA: "in some cases, the links can also be…
I think there is a lot of variance. The article also states about 266,141 “laser acquisitions” per day, which, if every laser link stayed up for the exact same amount of time, with 9000 lasers, means the average link remains established for a little less than an hour: 9000 (lasers) / 266141 (daily acquisitions) * 24 * 60 = 49 minutes
So some links may stay established for weeks, but some only for a few minutes?
In the long run that could become a massive strategic advantage for the US. A 2nd layer of resilience over undersea cables
Real time video and telemetry for military drones that’s nearly immune to electronic warfare counter measures is the real end game. The fpv drone carnage in Ukraine is currently limited to the contact lines plus or minus a few kilometers. Satellite comms change that drastically. Yes it’s available now but highly restricted.
> "We actually serve over lasers all of our users on Starlink at a given time in like a two-hour window" I can't figure out what this sentence means.
I think it means pretty much all Starlink users have at least some data go over laser links every two hours. Which is a bit of surprise to me, if true. I have a year or so of fine-grained latency detail taken with IRTT on a Starlink connection, I should sit down and see if I can see times I'm using a satellite. Latency is highly variable in Starlink though so it's pretty noisy data.
So that is "432 Mbit/s per laser, and 9000 lasers total". I don't know you guys but I find that statement much more relatable than "42 PB/day". Interestingly, they also say each laser "can sustain a 100Gbps connection per link" (although another part of the article even claims 200 Gbit/s). That means each laser is grossly underused on average, at 0.432% of its maximum capacity. Which makes sense since 100 Gbit/s is p…
Just because they seem grossly underused, there are probably plenty of other non-ideal constraints like power usage for instance.
I'd be interested in what the sustained power/thermal budget of the satellites is.
Earlier quoted context omitted.
> “Another really fun fact is that we held a link all the way down to 122 kilometers while we were de-orbiting a satellite,” he said. “And we were able to downstream the video.” > For the future, SpaceX plans on expanding its laser system so that it can be ported and installed on third-party satellites. The company has also explored beaming the satellite lasers directly to terminals on the Earth’s surface to deliver…
So what happens to the laser beam when there are clouds?