Ashutosh Sabharwal (via Rice University)

Full duplex Wireless Communication means getting your cake while you're eating it too. Ashutosh Sabharwal, a brilliant professor from Rice University, has made an amazing breakthrough in wireless data communications world of possibilities. The concept is like two people screaming at the same time in a large arena very far away from each other, but how can they hear each other? The answer is canceling out the sound of the screams coming from the sender so that the only sound they can hear is the sound of the other person's voice.

Sabharwal explained, "We send two signals such that they cancel each other at the receiving antenna -- the device ears. The canceling effect is purely local, so the other node can still hear what we're sending." These extra antennas send out canceling frequencies from the sending receiver.

Sabharwal continued, "We repurposed antenna technology called MIMO, which are common in today's devices. MIMO stands for 'multiple-input multiple-output' and it uses several antennas to improve overall performance. We took advantage of the multiple antennas for our full-duplex scheme, which is the main reason why all wireless carriers are very comfortable with our technology."

Rice University's idea was conceived and tested some months ago.

Now the team is back with a new goal, Sabharwal stated that their technology could be added to all cell towers, and no additional structures will be needed.  They have already "attracted the attention of just about every wireless company in the world." No wonder, the possibility of doubling the data throughput is quite exciting.

This technology will not be available until carriers upgraded their speed to "4 1/2G" or "5G" speeds, but the team is hopeful that this will be available in the next couple of years. Sabharwal is head of the WARP project at Rice University the acronym WARP stands for wireless open-access research platform. This enables them to be able to experience full-duplex wireless communication.

Eavesdropper

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