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German Researchers Hit 40 Gbps On Wireless Link
judgecorp writes "German researchers from the Fraunhover and Karlsruhe institutes have achieved 40Gbps transfers over 1km using a wireless link. The new record raises the hope that point-to-point wireless could be used instead of expensive fibers in some rural broadband applications."
Partially thanks to transmitting between 200GHz and 280GHz.
Here's another obligatory question
3. How many Australian Luddites care about what's happening in Germany?
Enquiring minds want to know
What part of "point to point" did you not understand?
1. How the hell is this going to fare in a real world test where a metropolis of people oversaturates the frequency?
From the summary.
...used instead of expensive fibers in some rural broadband applications
The higher the frequency, the more like light. It is a highly directional transmission, so unless there is another source of 200-280GHz signals within a few degrees of the transmitter sending in the direction of the receiver, there's not going to be interference.
When somebody tells you that fiber is a waste of money, ask them if we should stop building those expensive roads as well, because we can all fly helicopters instead.
Wireless LAN access points send at less than 1W (much less, depending on the regulatory domain), which is eventually converted to heat. Your brain on the other hand turns more than 10W of chemical energy into waste heat and you have only that stupid comment to show for it.
Well, I'm sure you've heard that Adolf Hitler was an Australian!
Religion is what happens when nature strikes and groupthink goes wrong.
The important facts are missing from both the summary and the English article. The german original has more info:
http://www.kit.edu/visit/pi_2013_12950.php
Basically, the important news is that they build new send/receive integrated chips that can be feed directly a optical link, transmit over radio waves and on the other side feed directly back to optical (fibre).
Formerly, you either have to:
* transcode from optical to radio link, and back on the other side, which is expensive (extra components), draws more power and is bulkier.
* OR use a laser, which is optical, and thus skips the transcoding, but fares bad in wether conditions like rain and fog
The new system combines the advantage of having an small 84x1.5mm) integrated chip system, which uses less power and can thus be cheaper with the advantage of a radio link over a laser link.
Of course it won't be unaffected by weather like a fibre laying in the ground - but it is still better (smaller, more robust, and still as simple as) than the existing laser links. And it is meant to be used where you can't just lay a cable, anyway.
Your average wifi antenna radiates 100mW.
Doing some very rough calculations in an hour that will heat a litre of water by about 0.08 degrees Celsius assuming that the water can't lose any heat to its environment.
Compared to say 2000 Watts for a microwave that does cook food with 'wireless energy'.
Also compare that with just the temperature from your car's engine and exhaust gasses.
I think the latter wins hands down.
yeah but helicopters are expensive compared to cars. I'm fairly certain that this setup is cheaper than the amount of fiber its replacing.
"His name was James Damore."
This band is not useful for long haul carriage due to atmospheric water vapor absorption. According to this chart, absorption between 200 and 280 GHz varies between 3 and 40 dB/km. That means at the low end only 50% of your signal is absorbed every km. At the high end, only 1/10,000th of your signal remains after each km.
this post speaks to similar issues including refraction.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
A 1km range is next to nothing for rural Australian
For Texans, 1 mile is "neighbors" . . .
. . . 100 miles is "just down the road" . . .
. . . 1000 miles is "just down the road, aways" . . .
Heh, I know people in the US like to think Texas is big, but the truth of the matter is that the area of the state of Texas is just under 700 thousand sq km, while the area of the state of Western Australia is a bit over 2.5 million sq km.
That's about 3.5 Texii*.
* I know - Texii probably isn't the correct plural for Texas, but Texases just sounded wrong.
You can never know everything, and part of what you do know will always be wrong. Perhaps even the most important part.
In rural Australia 100 miles is "neighbors" :(
Please don't mention Australia and neighbours in the same sentence. Now I have that terrible signature tune going through my head.