Radio breakthrough could double wireless performance

By on February 16, 2011, 5:22 PM
Stanford scientists have discovered a breakthrough that could double the speed of wireless networks. The technology reportedly allows radios to simultaneously send and receive signals over the same frequency -- something previously thought to be impossible. "Textbooks say you can't do it," said Philip Levis, Stanford's assistant professor of computer science and electrical engineering.

"The new system completely reworks our assumptions about how wireless networks can be designed," Levis continued. "When a radio is transmitting, its own transmission is millions, even billions of times stronger than anything else it might hear [from another radio]. It's like trying to hear a whisper while you yourself are shouting." The new technology resolves this by using two transmitters on each end.


"The two transmit signals interfere destructively at the receive antenna to create a dead signal that the receiver can't 'hear'," said Levis. "So you create this null position where the receiver can't hear that signal and so is able to receive packets from other areas." In doing so, performance is effectively doubled when sending and receiving data concurrently -- though it won't boost single-direction speeds.

The scientists noted that existing phone networks allow users to talk and listen at the same time, but they use a workaround that is more expensive and complicated than the new finding. It isn't clear when the technology will land in consumer electronics, but the researchers have applied for a patent and are tweaking signal strength to make it more suitable for Wi-Fi applications.




User Comments: 16

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Guest said:

Very impressive indeed! I personally never thought it was possible.

Kibaruk Kibaruk, TechSpot Paladin, said:

Cool, wireless is the future (Actually the present but... not that exploited) so go breakthroughs go.

jeffz6 said:

Breakthrough? this is 2011, "Back to the Future" has us flying in hover cars in 3 years and we are still working on lag free communications.

Guest said:

lol that was a movie real life actually moves alot slower. With governments, corruption and oil companies we won't see flying cars for another 500years.

Hell we would probably be alot further ahead if it wasn't for some of the current systems in place that hold back progress.

TomSEA TomSEA, TechSpot Chancellor, said:

This definitely goes into the mind-blowing department. Man, technology is growing by some sort of leaps and bounds within the last decade.

But I still want to see the first holographic home video game. Then I'll know we've "arrived."

Wagan8r Wagan8r said:

jeffz6 said:

Breakthrough? this is 2011, "Back to the Future" has us flying in hover cars in 3 years and we are still working on lag free communications.

Yeah, and my movie script "The Year of Awesomeness" has interstellar worm hole travel, freeze dried Insta-Food (just add water!), shrink-rays, enlarge-rays (bom chica wa wa!), nuclear powered coffee machines, auto-scrubbing showers, cyborgs, solar powered brain chargers, printers that don't jam, teleportation, telekinesis, telepathy, television telephones, telephone televisions, telephone televisions with telepathic, telekinetic, and teleportation transmission terminals, and shorts that don't hike up your crack. And we're still working on lag free communications!

lawfer, TechSpot Paladin, said:

wagan8r said:

jeffz6 said:

Breakthrough? this is 2011, "Back to the Future" has us flying in hover cars in 3 years and we are still working on lag free communications.

Yeah, and my movie script "The Year of Awesomeness" has interstellar worm hole travel, freeze dried Insta-Food (just add water!), shrink-rays, enlarge-rays (bom chica wa wa!), nuclear powered coffee machines, auto-scrubbing showers, cyborgs, solar powered brain chargers, printers that don't jam, teleportation, telekinesis, telepathy, television telephones, telephone televisions, telephone televisions with telepathic, telekinetic, and teleportation transmission terminals, and shorts that don't hike up your crack. And we're still working on lag free communications!

I laughed out loud while reading this!

Staff
Matthew Matthew, TechSpot Staff, said:

Haha, that's signature worthy wagan8r.

RaiDeR55 said:

I with you on that one Tom.. Me too

motrin said:

hha

thats has to be and is going to be the best user made post of twenty eleven!

Guest said:

Printers that don't jam? I call BS on your utopian vision.

hitech0101 said:

Well i thought we already had this technology but now i know we don't.

Benny26 Benny26, TechSpot Paladin, said:

Wagan8r said:

...and shorts that don't hike up your crack

Aye, we can all hope..I fear i shall be an old man by the time though

Loads of wacky stuff like the hover car could in fact be made..There's already the technology available (like the marrage of the car with the Harrier jump jet for example). It all comes down to the "financially viable" side of things. I guess that's why there's no such thing as currency in Star Trek

I agree that this Radio breakthrough is very impressive.

Guest said:

The idea is very old. It' called the RF nulling technique. The main problem is that how much TX signal can be canceled. Let's do a simple calculation: Average WiFi TX signal 10 dBm, RX signal -70 dBm. So the TX/RX ratio is 80 dB. Say, you need 20 dB signal to noise ratio to correctly decode the signal. This means you need to suppress the TX signal from 10 dBm to -90 dBm: a 100 dB gap! Now, with a very expensive hardware, you may get the TX cancellation of less than 40 dB. So the remaining TX signal is still 60 dB higher than the RX signal. It's almost impossible to go any further. There have been many people in the past trying to solve this interference cancellation problem. Spread Spectrum is one of them. They all have serious limitation. I personally don't believe the current "Standford Idea" will go anywhere in near future. However, I do feel proud of these young researchers for their endeavor.

James

Kibaruk Kibaruk, TechSpot Paladin, said:

The problem was that this was imposible according to books... and they cracked it... MIND BLOWING kind of stuff.

I'm also awaiting for the day printers wont jam... I will be so so happy that day...

Guest-borg said:

Does this mean I can listen to two wirelesses at the same time, or would I have to turn the sound down on one of the wirelesses.

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