Full-duplex communications is a system that allows for simultaneous transmission and receiving of data through a single antenna. Previously, single antenna devices would have to alternate between sending and receiving, slowing both of the processes.
“The way I like to think about it is it’s like having a conversation between two people where both people can talk at the same time and still listen to what the other person is saying,” says lead researcher Harish Krishnaswamy
“So obviously you can imagine that if you’re able to do that, conversations would take half the amount of time that they take right now. And similarly, in full duplex, if we could have transmitters and receivers working at the same time, at the same frequency, we’d immediately be able to double wireless capacity at the physical layer.”
This advancement of wireless technology was achieved by electrical engineers at Columbia University. The new chip the team calls the circulator breaks Lorentz Reciprocity which is a principle in electromagnetics that states that waves must travel in the same manner both forward and backwards.
“Reciprocal circuits and systems are quite restrictive because you can’t control the signal freely,” said one of the team, Negar Reiskarimian, in a press release. “We wanted to create a simple and efficient way, using conventional materials, to break Lorentz Reciprocity and build a low-cost nanoscale circulator that would fit on a chip.”
Lorentz Reciprocity is disrupted by magnets. But magnets and silicon chips don’t play well. So the researchers emulated the effects of magnetism by using capacitor signals. The effect is cancelling the reciprocity, thereby allowing two-way signals on a singular antenna.
This development could completely change how our wireless system works. By doubling our capacity of every smartphone, tablet and personal communication device the possibilities are endless.