updated 06:35 pm EST, Fri March 2, 2012
Researchers 'twist' airwaves, boost bandwidth
A team of Swedish and Italian physicists has developed an experimental technique that has the potential to dramatically increase both speed and bandwidth using the electromagnetic wireless spectrum. According the BBC, the method exploits a property of physics that can be observed in space known as the ‘orbital angular momentum’ of airwaves. Already in discussions to commercialize the technology, the researchers have used the phenomenon to impart the waves with a ‘twist’ to fit multiple data streams where previously there was only room for one.
The research conducted by Bo Thide of the Swedish Institute of Space Physics and his Italian colleagues has been published in the New Journal of Physics. The team successfully beamed two separate signals over one band using the 2.4GHz frequency by crudely splitting one side of a satellite dish (pictured below) and separating the two resulting edges. The beam was then transmitted with one wave slightly ahead of the other creating a corkscrew-like effect.
‘For me it was obvious this would work,’ said Prof. Thide. ‘Maxwell's equations that govern electromagnetic fields are... the most well tested laws of physics that we have.’ ‘We did this because other people wanted us to demonstrate it,’ he added.
Prof. Thide said the inspiration for the experiment came from observing the orbital angular momentum of light than can be seen manifesting around black holes. He had been mulling the idea of applying the same concept to radio frequencies after theoretically demonstrating it in an article published in Nature Physics demonstrating that spinning black holes can produce ‘twisted’ light.
Following the successful experiment, Prof. Thide says that he and his team have been engaged in talks with industry to develop a system that can transmit multiple frequencies over single bands using the different orbital angular momentum technique.