Wireless spectrum is a finite natural resource, and all it takes is a look at recent deals like Verizon's $3.6 billion and AT&T's $1.9 billion purchases to see that it's in high demand. Since we can't make more spectrum, all we can do is use it more effectively, and researcher Fabrizio Tamburini and his team think they know just how to do it. They say that by twisting radio waves we'll be able to send multiple discrete signals over the same frequency, giving us, in theory, "an infinite number of channels in a given, fixed bandwidth." The technique uses a modified transmitting dish that's shaped like a portion of a corkscrew to send out signals called radio vortices with different orbital angular momentmum states (i.e. degrees of spin), each carrying different sets of data.
It does sound a bit far-fetched, but thankfully this isn't just a hypothetical solution. The researchers have just been published in the New Journal of Physics, where they discuss the findings of a proof-of-concept experiment that they performed in Venice last summer. The team transmitted two signals, one without any spin and another with a spin to two different receivers. Both signals were sent in the 2.4GHz Wi-Fi band over a distance of 442 meters. In their report, the researchers say that the signal was weaker than would be expected of a traditional method, but not by much. Only time will tell if the technology can be feasibly implemented in consumer and commercial applications, but if twisting radio waves can help reduce wireless interference, then we're all for it. Check the video below for an overview of the entire project, but skip to 7:28 to see the test in action.