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A High-Bandwidth Interplanetary Connection
sciencehabit writes "A new study suggests that by twisting laser light, scientists could pack enough information into interplanetary beams to speed up extraterrestrial communications to the multi-gigabit level. The pulses would be passed through a hologram or multimode optical fiber, which twists the light. On the other side, a telescope would focus the light and a second hologram, or fiber would decode the signal. That could allow much more data-rich communication between, say, Earth and probes on Mars, the researchers say. Closer to home, the approach could provide Internet links of 100 gigabits per second."
> Hemmati and his colleagues estimate that receiving OAM data from a transmitter as distant as the sun would require a kilometer-wide telescope.
Sounds like even someplace closer like Mars is going to take an impractically large receiver.
--- Mercutio was right.
We need faster speeds here down on earth before we think of these "multi gigabit" speeds for interplanetary communications..
Nothing here... So... SHOOO!!!
They're going to have to do something about the terrible ping times. Its orbit is about 1.5AU, so when it's close to the Earth, the round-trip ping time will be about 8 minutes. When it's on the opposite side of the sun, it'll be about 40 minutes.
Closer to home, the approach could provide Internet links of 100 gigabits per second
Throttled down by your ISP to 24 megabits per second
Summation 2
Should give limitless bandwidth.
Latency of course is the factor here.
EMail: 0110001101100010010000000110001101110010 0110000101111010011011100110000101110010 0010111001100011011011110110
That's great, but the roaming charges will kill you.
Isn't the limiting factor for current bandwidth power rather than speed anyways? My understanding they've long had the technology for much high bandwidth but the limitations are always power demands.
Secondary to power is usability. There's a big difference between pointing an antenna in the general direction of home and precisely aiming a laser million of miles away. Several orders of magnitude more accuracy is required.
Personally I don't find anything practical about this project. At least not today.
Because most space probes now-a-days are data rate limited. LRO, MRO, Dawn, etc., all could take more data, if we could get it back.
I love the dumptruck analogy, but I'm not convinced of the math. Let's see if we can work it out:
A dumptruck has a volume of approximately 722 cubic feet (17 x 8.5 x 5) source. Converting that gets us 1,247,616 cubic inches.
A harddrive is 3.5" x 102 mm x 25.4 mm source. Or about 14 cubic inches.
This means that roughly, we can fit about 89,115 hard drives into a dumptruck, assuming everything fits perfectly.
The largest commercially available 3.5" harddrive is 3 TB. This means that we're going to have 267,343 TB on our truck.
Driving across the country takes 26 hours assuming no stopping. Source
This yields 267,343 TB / 26 hours = 2,138,744 Tb / 26 hours = 2,138,744 Tb / 93,600 seconds = 22.849 Tbps = 22,849 Gbps.
Compare that to a commercially available 10Gbps link available from any business class provider, and you're going to trounce them. The latest stuff is 100Gbps, which you should be able to get a hold of if you're willing to shell out right now, but it's still a blow out. You are indeed correct.
A couple of other items to note:
1. You can add a day at the front and a day at the back to load and unload the truck and you're still around 10 Tbps.
2. If you add another 2 days to collect all the data, write it to harddrives and then do the same 2 day process at the back end, you're still around 5 Tbps.
3. A more fair comparison is probably not using such a slow mechanism like a dump truck (I understand it's there to prove a point in your analogy). But instead use a cargo plan. You'll get 23,200 cubic feet of storage out of a Lockheed C-5 Galaxy cargo plane which is about 32 dumptrucks. Also, you can get across the country in 6 hours, even assuming some landing and takeoff. If you still assume it takes several days to load and unload the plane, you'd probably be up in the 1 Pbps range.
4. I was trying to think what would be the fastest way to load and unload the truck, and then I realized I was insane for trying to calculate such a dumb thing. The real answer here is to build storage arrays on the truck and have it roll back and forth. Essentially, it's a mobile data center. You have a few hundred 10 Gbps ports on the rear of the truck to plug in, and you can download all of your data on and off of it pretty quickly, without manual labor beyond plugging in a port. Further, this would be a very fun way for the Pirate Bay, or someone similar to distribute data if they ever wanted to go physical (and thus blatantly break the law). Once a week, the Pirate Bay truck would roll into town and all the kids could plug in the back to download petabytes of information before it leaves for the week. A fun concept, if nothing else.
Disagreeing with me does not mean you get to mod me troll.
Rather than actually doing it, couldn't we just auction the interstellar bandwidth to Google, Verizon, ATT, Sprint, etc.? Then we'd close the federal deficit! Centuries from now, they'd make the money back on roaming charges. We've been passing the buck to our kids, time to exploit the great-great-great-grandkids.
Gently reply