Scientists Crack Simultaneous Two Way Single Channel WiFi Communications
Posted: 16th Feb, 2011 By: MarkJ
Scientists working at Stanford University in California could be on the verge of making Wi-Fi networks, including other wireless communication solutions, significantly faster after they developed a new technology that allows the radio signals to be sent and received simultaneously on a single channel.
Philip Levis, Assistant Professor of Computer Science and Electrical Engineering, said:
"Textbooks say you can't do it. It's like two people shouting messages to each other at the same time. If both people are shouting at the same time, neither of them will hear the other. The new system completely reworks our assumptions about how wireless networks can be designed."
It might surprise some readers to learn that wireless networks haven't been able to do this before. In reality radio traffic can flow in only one direction at a time on a specific frequency, which prevents truly simultaneous two-way single channel communication. As a result most networks use a lot of clever and expensive tricks to avoid the problem, such as channel changing and frequency hopping.
The new solution, which could "at least double" the speed of existing networks, essentially makes it so that the radio receiver can filter out the signal from its own transmitter. This allows weak incoming signals to still be heard and is similar to how noise-cancelling headphones work.
Perhaps the most impressive thing about their development is that it's incredibly simple and could have significant implications for radio networks and communications across the world.
However there are a few problems that need to be overcome first, not least with distance and transmission strength. Receiving a weak signal is all very well in the lab but it makes long range communications more difficult.
The team are confident that these problems can be overcome and already have a patent on their technology. Check out the above video for a better explanation.