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Researchers Unveil High-Speed Laser Communications Device For Space
coondoggie writes "Using lasers to communicate quickly through the long distances of space has generally been the purview of science fiction. But researchers at the National Institute of Standards and Technology (NIST) and NASA's Jet Propulsion Laboratory (JPL) are out to change that notion with a prototype array (pdf) that can read more information — and allow much higher data rates than conventional systems — than usual from single particles of light. Lasers can transmit only very low light levels across vast distances, so signals need to contain as much information as possible, NASA said."
Using lasers to communicate quickly through the long distances of space has generally been the purview of science fiction.
The ESA Artemis satellite used the SILEX laser link to communicate with the SPOT-4 satellite. It was not the first project to use laser communications in space either. The datarates mentioned in this article are better than those of SILEX though.
Does it matter whether the emitted photons are from RF or Light? They both travel at the same speed.
I've invested way too much time to movies and books to not see laser communications, to at the very least, to the moon in my lifetime. There are many authors that have enjoyed my 25 cents or less of royalties they received that should finally be vindicated by including laser based communications in their books!
Does it have a Shark2Shark protocol (S2S) implemented?
I've found that most WiFi connections bragging about being highspeed, are not that far from being modem speeds. If it's high-speed, the marketers feel the terminology forces the users into giving them more cash. Evey time I here the phrase, I figuartively want to randomly strangle someone, anyone working in sales.
Lasers at modem speeds; there's a thought, or not.
...unless their laser can send signals traveling faster than the speed of light.
Even out of a high-gain antenna radio waves spread enough to lower EIRP a lot compared to a laser.
Conversely, optical comms could probably be received on any telescope on the planet. We already have a wide variety of equipment setup for receiving very faint optical signals. Just a matter of hooking that into a modulator (he says, casually describing several Ph D projects and millions of dollars).
I wonder if this will have any application to the delay-tolerant networking concepts for interplanetary networking done by Vint Cerf.
Keep the faith, share the code
According to the article, they use positioning information to generate additional bits of information. My question is how do they determine position at large distances when both bodies are obviously not standing still. The only thing I can think of is having one constant laser being used as a position reference for all communication lasers. Of course, they still have to be able to hold the laser on the detector array.
...also exploits polarization to a high degree. In fact, many developmental optical communication systems exploit polarization purity for higher base digital transmission, and even if polarization modulation slows things down for some schemes, the resulting bandwidth can overcome the obstacles by an order of magnitude or more over the reduced rate of the mux/demux. The issues with these schemes is more about cost. But most of these programs are directed at n-fold increases in existing optical fiber network bandwidth. Their time will come.
I think the equipment is of comparable reliability: doped fiber amplifiers, etc. are standard items. We've been flying pretty exotic lasers for a lot of years.
But wouldn't the fibers locally degrade over the years of being exposed to the effects of galactic radiation (heavy ion bombardment outside Earth's magnetosphere), paving way to some sort of local cascade failure (given the EM energy densities involved)? Klystrons don't face nearly the same issues.
Ezekiel 23:20