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New Fiber Optic Signal Processing Technique Doubles Communication Distance
hypnosec writes: Researchers at University College London (UCL) have demonstrated a new technique for fiber optic signal processing that doubles the distance at which data travels error-free through transatlantic sub-marine cables. The UCL research, published in Scientific Reports, has the potential to reduce the costs of long-distance optical fiber communications as signals wouldn't need to be electronically boosted during their journey, which is important when the cables are buried underground or at the bottom of the ocean. The study reports a new way of improving the transmission distance, by undoing the interactions that occur between different optical channels as they travel side-by-side over an optical cable. By eliminating the interactions between the optical channels, researchers increase distance signals can be transmitted error-free from 3190km to 5890km, which is the largest increase ever reported for this system architecture.
I guess they didn't teach you how to round.
No, it means they can oversubscribe now by twice as much as they do now.
NO technology will cause your internet to get cheaper -- the assholes who run telecom companies see to that.
Lost at C:>. Found at C.
EDFA.
"National Security is the chief cause of national insecurity." - Celine's First Law
Anything modern is running EDFA's where fiber is doped with Erbium and a pump laser is mixed in they get about 40db of amplification with a 100ma laser. Great part is it's not signal speed dependent as it's an all optical all analog method. The old way was to put a receiver and transmitter coupled back to back used a lot of power and was specific to a speed.
No sir I dont like it.
But there are still going to be amplifiers. They are referring to eliminating transponders, which we already don't use for modern sub-sea links. This is basically just 16QAM, but instead of using 4 symbols over 1 frequency, it's 2 symbols over 2 frequencies tightly spaced together. It's been understood for a while that widening the channels was probably the only way to go beyond 100gbps for a transmitter/receiver.
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"...error-free through transatlantic sub-marine cables." So those of us in Australia, which is bordered by bodies of water such as the Pacific and Indian oceans, amongst other, and NOT the Atlantic will continue to get error riddled internet. Typical Pom's, can't trust them further than you can smell them.....
Nothing bizarre here. Sharks (and other cartilaginous fish) have electroreceptors to hunt and track their prey, so anything generating an electromagnetic field will atract sharks to check if it's a viable food source.
http://en.wikipedia.org/wiki/Ampullae_of_Lorenzini
Though the article is not about speed, let me quote wikipedia on that matter, as I was shocked/amazed the other day when I found how slow the communication over the cables was in the beginning: ..had been vastly improved.. could transmit eight words a minute"
"The reception was very bad on the 1858 cable, and it took two minutes to transmit just one character (a single letter or a single number), a rate of about 0.1 words per minute."
"..the 1866 cable,
This sort of thing is measured in dBm to make the math easier. Decibel Milliwatts, where 0 dBm = 1 mw and it's a logarithmic scale up and down from there.
Individual channels are on the order of 0 to 5 dBm, or 1 to 3 mw. The composite signal coming out of an amplifier, which consists of multiple channels, is on the order of 20 dBm depending on how many channels are active and what the reach of the amplifier is. That's about 100 mw. Definitely a laser safety concern, but not military style death ray.
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