Two way, simultaneous, wireless communications over a single channel has been demonstrated by Stanford's researching engineers Jung Il Choi, Mayank Jain, and Kannan Srinivasan.
"Textbooks say you can't do it," said Philip Levis, assistant professor of computer science and of electrical engineering. "The new system completely reworks our assumptions about how wireless networks can be designed." But wait, I can talk and listen on my cell phone! The research team claims the way companies achieve this effect is much more costly and cumbersome than there method.
Transmission of a radio signal is much more powerful than what the device needs to listen to. Levis explains, "When a radio is transmitting, its own transmission is millions, billions of times stronger than anything else it might hear [from another radio], It's trying to hear a whisper while you yourself are shouting." They defeated this issue with a simple idea: "What if radios could do the same thing our brains do when we listen and talk simultaneously: screen out the sound of our own voice?" Similar to noise cancelling headphones, the transmitter filters out what it is sending. Immediately the incoming signal can be heard.
Levis explains a major use of the technology in the future, " With current systems, if two aircraft try to call the control tower at the same time on the same frequency, neither will get through. Levis says these blocked transmissions have caused aircraft collisions, which the new system would help prevent."
The now patented technology has the potential to double data rates in every communication system. The team continues to work towards extending the range and power of their device.
Eavesdropper
