I recently read a very interesting paper that discusses one of the coolest wireless comm-related projects I have seen around for a while. A team of researchers from University of Washington presented this paper at Sigcomm this summer in Hong Kong. The paper was, by the way, awarded with the best paper award.

The idea is simple but could lead to a whole new technology with a great spectrum of applications. These researchers have designed a simple communication system that operates with no need for battery or power. Essentially, the nodes use the signals that are transmitted around them (for example TV signals) and modulate them in such a way that they are able to communicate with each other. Essentially, is a further step more from, for example, RFID tags that use the power of the transmitted signal to power themselves and send a reply. Although ambient backscatter (which is the name the authors give to this technology) has very short range, it could potentially be used for multiple applications, including certain types of wireless sensor networks.

The ambient backscatter project website presents the following video. One can observe the huge antennas these small devices have, which indicate that they operate at not too high frequencies and give an idea of the very low power they operate at. No room for inefficiencies of small twisted or patched antennas. They keep it simple for now with a dipole tuned at the wavelength.

By the way, this project is lead, among others, by Prof. Shyam Gollakota. He was recently awarded with the prestigious ACM Doctoral Dissertation Award and shortly after got a position as Assistant Professor at the University of Washington. Good stuff.


While browsing more stuff for this post I found about another project from Gollakota: WiSee. Again, really cool stuff. They are using subtle variations in wireless signals when a person moves to do gesture control. Very interesting. Check it out here.