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I accidentally refreshed the screen, fuuuuuck


Can anyone explain how upload would work? How can an unmodified cellphone upload data to a satellite?


There are a few factors that make this possible:

1. As others have pointed out, the link budget (how much energy loss a particular radio link can handle before it is broken) for D2C satellites assumes a nearly direct line of sight from your handset to the satellite. This is much easier to achieve with satellites in space than it is with traditional cell towers that might have numerous walls/buildings in the way.

2. The D2C satellites use massive phased array antennas that are able to point a very narrow beam very accurately to the ground. This provides a substantial amount of antenna gain that further helps the link budget. The gain from the antennas allows the satellites to pick up even relatively weak signals from a handset.

There are other tricks as well, but these account for the largest differences. Of course, doppler gets in the way, but it is a solvable problem.


So the satellite can point a narrow beam. How does it handle multiple connections. Can it aim 1000s of beams at once?


In theory, yes. Phased arrays can steer as many independent beams as the connected electronics support. I real life, it's probably going to be dozens or maybe hundreds of beams.


I guess the narrow beam, covers quite a bit of area on earth.

I guess the "narrow" in the current context is the beam widening to hundreds of miles on earth.


IIRC the current Starlink beams are of order 10 miles on the ground. So much narrower than you guess.


My thinking is that you can think of Starlink satellites as LTE towers that just happen to be ~350 miles away from your phone. It happens to work because while they are far away, the satellites have a very clear line of sight (directly down) with few (no) obstacles.

The complication is that the base stations will be moving much more rapidly than traditional terrestrial towers.


very slowly, with the radio at maximum power, and no obstructions


Yeah, this is going to decimate your battery life. It's great to have in an emergency, don't get me wrong, but I'd probably leave data off otherwise when out remote.


Your cell phone uses the nearest base station, the base station will handover to the satellite infra.


Why do you need satellite if you can connect to a base station? This makes no sense.

No, they claim direct phone to satellite link.


No, that’s just satellite backhaul for a cell tower. That’s not hard, but also typically if you can get power to a base station you can run fiber along the same poles the power runs on.

This is direct from handset to satellite, it’s clearly explained in the link.


> That’s not hard, but also typically if you can get power to a base station you can run fiber along the same poles the power runs on.

Or a directional microwave link to the next station in sight.


Aren't those satellites going to generate simulated cell tower signals so you won't require any modification whatsoever?


Worthy of the best TED talk ever: https://youtu.be/zAFcV7zuUDA



I've been using the secure version of this knot for a few years now, and I've been entirely satisfied with how it holds up in the real world!

https://www.fieggen.com/shoelace/secureknot.htm


What does that even mean? lol. The Ted way still works and the shoe laces have not come undone in 10 years since I've been using it, so why would I change method?


It's quite hard to maintain tension with the Ian knot and it also doesn't speed up the initial twist. It's a good party trick though!


You can just leave the initial twist on the shoestring


Am I really the only one thinking this is all AI-generated and completely fake?


whoops


The market have never been more ripe for a new player.


Maybe he's talking about the hyperloop.


> Data on the tape is stored at a record-breaking density of 317 gigabytes per square inch

Me wondering about those micro SD cards that can store 1Tb.


Maybe around an order of magnitude more. The big difference is that square inch of tape might be 3-5 orders of magnitude cheaper to manufacture.


Those SD cards aren't close to a single layer, so it's not really equivalent.

Ad absurdum, stacking two Micro SD cards on top of one another hasn't just doubled your density even though surface area is unchanged.


Fair enough but chances are the tapes will have a much longer lifetime for storing data, which is the primary use case for this sort of thing.


The density of flash memory is competitive with magnetic tapes, but the retention time is too low, making flash memory completely unusable for archival storage, even if it would have been as cheap as magnetic tape.

In theory, write-once memory cards, using some kind of antifuses, could be designed to have a lifetime good enough for archival storage, but nobody has attempted to develop such a technology, because it is not clear if there would be a market for them.

Most people do not think far ahead in the future, so they do not care much about archival data storage, until it is too late and the information had already been lost.


> The density of flash memory is competitive with magnetic tapes, but the retention time is too low, making flash memory completely unusable for archival storage, even if it would have been as cheap as magnetic tape.

I disagree that it's unusable. You'd end up with a puck the size of a data tape that can archive a petabyte of data and needs to be plugged in to a 5 watt power supply for long term storage. That's not super onerous. Then consider that tapes need to be stored at exactly room temperature with 20-50 percent humidity, while this puck would barely care about environment at all. And you could plug it directly into a computer without a $5k drive. Honestly it sounds pretty good to me. We just need to drop the price of flash by a factor of 20 to make the scenario happen.


It probably references the density within the data tape world, which is significant as there could be other ways to achieve a higher total storage, but this is one of the major components here it seems


Epic was simply asking for it


...what?


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