A wireless radio that can send and receive signals at the same time

Radio waves to make the world go around.  They make it possible for communication and navigation satellites, modern aviation support and provide access to wireless Internet.  A feature of radio technology is that traffic flows in one direction at a time on a specific frequency. This is why pilots, police and others walkie-talkie frequently use "over" as they take turns speaking.

But now researchers at Stanford have developed a way that allows wireless signals being sent and received simultaneously on a single channel. Their research could help build networks faster, more efficiently, at least double the speed of existing networks.

"Textbooks say that you can do," said Philip Levis, Associate Professor of computer science and electrical engineering. "The new system proposes completely our assumptions about wireless networks can be designed," said in a press release from the University.

Levis and his team made the discovery is based on a seemingly simple idea. What if radio could do the same thing that our brains do when we have to listen and speak simultaneously: exclude the sound of our voice?

The main obstacle to simultaneous two-way conversation is that incoming signals are overwhelmed by their radio transmissions, making it impossible to talk and listen at the same time.

"When is transmitting a radio, its transmission is million, billion times stronger than anything else that you may hear [from another radio]," Levis said. "Trying to hear a whisper, while she screams".

The researchers reasoned that, if the signal from its transmitter could filter a radio receiver, weak incoming signal could be heard. "You can make it so that you don't hear your cry and you can hear someone whisper," Levis said.

Each radio knows exactly what is being sent, and then what should filter its receiver. The process is similar for noise canceling headphones.

Up next for the team is to increase both the strength of broadcasts and distances to work before the technology can be of any practical use in WiFi networks.

But even more promising are the implications of the system for future networks. "Once a hardware and software are built to take advantage of simultaneous two-way transmission, there is no estimate the scale of results," said Levis.

Watch the accompanying video to see the set-up wireless in action.

Christopher Jablonski is a freelance technology writer.