Full Duplex Wireless Tech Could Double Bandwidth 60
CWmike writes "Rice University researchers announced on Tuesday that they have successfully demonstrated full-duplex wireless tech that would allow a doubling of network traffic without the need for more cell towers. Professor Ahutosh Sabharwal said the innovative technology requires a minimal amount of new hardware for both mobile devices and networks. However, it does require new standards, meaning it might not be available for several years as carriers move to 5G networks, he added. By allowing a cell phone or other wireless device to transmit data and receive data on the same frequency, unlike with today's tech, the new standard could double a network's capacity. Rice has created a Wireless Open-Access Research Platform (WARP) with open source software that provides a space for researches from other organizations to innovate freely and examine full-duplex innovations."
more on why this is difficult (Score:5, Informative)
The idea, as they mention, has been around for a while, in fact since at least the early 1970s, with some information-theoretic work putting bounds on ideal full-duplex operation. The main idea is that you can cancel your own transmitted signal locally because you know what you're transmitting. The difficulty is that the transmitted signal is much stronger locally than the received signal, so there is little margin for error for imperfect cancellation; even if you cancel out 99.9% of the signal, there might still be too much noise left to decode the incoming signal. Errors can come from nearly anything; slightly imperfect knowledge of the characteristics of your device, changes due to weather or motion, interference from surrounding objects, etc.
Also note that terminology here is a bit confusing. In some uses (esp. radio), "full-duplex" just means any system that is capable of having people speak in both directions simultaneously, even if it's done by using separate frequencies for each direction, or by using a multiplexing scheme. In contrast, this usage of full-duplex means that both directions are transmitting simultaneously on the same channel, without segmenting or multiplexing it.
I don't actually know how they solved the problem, though, and the article is light on details.