Scientists hit wireless speeds of 2.56Tbps using light vortex beams

By on June 26, 2012, 4:30 PM

Researchers at USC, JPL and Tel Aviv University have managed to transfer 2.56 terabits of information by multiplexing 8 x 300Gbps "twisted" streams of visible light into a single beam. The feat exploits a phenomenon which, up until recently, scientists thought may have been impossible to achieve with light: orbital angular momentum (OAM). 

OAM, the way a wave can be made to twist around itself, is what makes the team's discovery particularly exciting. It also makes their findings incredibly useful for wireless data transmission. Making light beams spiral to create an optical vortex is not necessarily a new idea, but putting that phenomenon to work for the transmitting information is something researchers have been striving for.

Currently, existing wireless technologies (i.e. radio waves) employ SAM (spin angular momentum) but not OAM. SAM differs from OAM in the same way that the Earth's spin differs from its orbit around our Sun -- imagine SAM as a spinning planet and think of OAM as the orbit of that spinning planet as it travels around a star.

Just as the rotational speed of SAM can be used to represent different numbers (i.e. data represented by the number of spins per second), the tightness of spirals produced by OAM can also represent numbers (faster the twist, tighter the spiral). Ultimately, researchers have managed to simultaneously utilize both SAM and OAM to represent data with light, giving them tremendous potential to represent huge ranges of information and deliver it at light speed.

Despite the amazing potential of their findings, there do exist complications. For one, researchers only managed to transmit data across one meter of distance. Regardless, the team believes it can achieve similar results using links over 1km in length. 

Additionally, because the beams are made entirely of visible light, such light vortices require clear line-of-sight between the sender and recipient. This means you most likely won't be replacing your Wi-Fi network with a wireless phase-modulating vortex beam station anytime soon.

There's also the matter of turbulence or otherwise less-than-perfect conditions for the medium in which the light passes through (i.e. the atmosphere). As a result, researchers suggested that communication between satellites may represent an ideal scenario, but there's much work to be done on producing hardware and software capable of managing light-based OAM. 

Previous research does suggest such beams could be contained within fiber optic cabling, but we already have plenty of room to grow there as it is. The real excitement seems to be transmitting data wirelessly, an area where our future endeavors may be limited by the finite amount of usable radio spectrum available. Leveraging light-based OAM could potentially provide an immediate solution to this problem.

The full paper can be found at Nature (only the abstract is free), but ExtremeTech provides a great look into their findings.




User Comments: 18

Got something to say? Post a comment
ikesmasher said:

*8x300Gbps.

multiplex= A system or signal involving simultaneous transmission of several messages along a SINGLE channel of communication.

MilwaukeeMike said:

"Additionally, because the beams are made entirely of visible light, such light vortices require clear line-of-sight between the sender and recipient. This means you most likely won't be replacing your Wi-Fi network with a wireless phase-modulating vortex beam station anytime soon."

That's a bummer... I was looking forward to coming home with one and saying 'Honey! I bought a wireless phase-modulating vortex beam station!'

Staff
Rick Rick, TechSpot Staff, said:

*8x300Gbps.

multiplex= A system or signal involving simultaneous transmission of several messages along a SINGLE channel of communication.

I added, "into a single beam" to satisfy your pedantry. :-)

Guest said:

hmmm very interesting...this will prove VERY useful for the satellite companies...imagine a clear line of sight if you live in the country. No cable, barely any cell phone reception...this would do wonders for everyone. This is really big, I can't wait to see what they do with it.

Guest said:

So would that take a bit of a toll on my smartphone battery? Because we need to move on from LTE. It's getting pretty long in the tooth... :p

3DCGMODELER 3DCGMODELER said:

Or puting it thru Glass Fibers...

ikesmasher said:

hm yea, that would make sense for satalllites maybe...its gonna need a hell of a light though...

tonylukac said:

I don't see how light would go thru cloud cover from a satellite. My brothers radio satellite dish fails when it merely rains.

ikesmasher said:

well maybe if you live in the middle of a desert.

spydercanopus spydercanopus said:

300Gbps! *drools* And people say there is no god...

Guest said:

"The real excitement seems to be transmitting data wirelessly, an area where our future endeavors may be limited by the finite amount of usable radio spectrum available."

Visible light is part of the electromagnetic spectrum and is limited as well. Right now our phones are using code division multiple access (CDMA) which allows multiple users to occupy the same exact frequency. That was our fix to the problem of finite radio spectrum.

The reason they're able to increase the speed is because the wavelengths of visible light are shorter. Long story short the amount of spectrum available is irrelevant.

Arris Arris said:

I don't see how light would go thru cloud cover from a satellite. My brothers radio satellite dish fails when it merely rains.

researchers suggested that communication BETWEEN satellites may represent an ideal scenario

DanUK DanUK said:

Oh man, the physics going into this is incredible/fascinating. The amount of technology like this we're seeing emerge these days... I can't wait to see what sort of devices we'll have 5/10 years down the line.

DanUK DanUK said:

I don't see how light would go thru cloud cover from a satellite. My brothers radio satellite dish fails when it merely rains.

Yeah I think they were talking about between satellites in space for example. Space = almost zero interference.

LinkedKube LinkedKube, TechSpot Project Baby, said:

You can move to places like Arizona or Utah U.S just to name a few, or the middle of Austrailia to avoid a lot of cloud cover.

jacques said:

and also not very cloudy in south africa hehe

Guest said:

so.. Does apple have a wireless phase-modulating vortex beam app yet?

Load all comments...

Add New Comment

TechSpot Members
Login or sign up for free,
it takes about 30 seconds.
You may also...
Get complete access to the TechSpot community. Join thousands of technology enthusiasts that contribute and share knowledge in our forum. Get a private inbox, upload your own photo gallery and more.