Nov 06, 2006This article was originally published by RFID Update.
November 6, 2006—After a few years commercializing his technology at Dust Networks, a key innovator of so-called smart dust has returned to the lab to extend the technology's capabilities into the RFID realm. According to an article in eWeek, UC Berkeley electrical engineering and computer science professor Kristofer Pister believes potential enhancements in meshed sensor networks could fulfill RFID's promise of asset visibility. The only difference is: Pister's smart dust would not require the same expensive reader infrastructure.
"The sound bite on RFID is that most people think it's going to tell them where their stuff is at all the time. In fact, what RFID does is tell you where your stuff was the last time it went through a reader successfully," Pister is quoted as saying. "Contrast having to put in readers everywhere you want [information] to just having the tags know where they are and having that broadcasted every few feet."
Pister is focusing on a technique called RF Time of Flight, which would allow the many sensors, or "motes", that comprise a mesh network to calculate their locations. Each sensor measures the time it takes radio frequency signal to reach its neighboring sensors, a measurement which correlates to distance. With enough such measurements, an approximate location of the mote can be ascertained.
Recall that a mesh network is a collection of physical sensors distributed across a geographical coverage area. The sensors detect environmental characteristics like temperature, vibration, and light. They also detect each other, forming an ad-hoc network based on the presence of one another. They are then able to daisy-chain the data they collect in the field back to a central repository. The applications are myriad, but favorite examples include gathering battlefield intelligence or monitoring ecosystem and habitat changes.
Smart dust is a futuristic extension of this concept, in which the sensors are cheap, expendable, and the size of a speck of dust.
To enable RF Time of Flight will require, among other things, the incorporation of radio frequency capabilities onto the sensor chips, something Pister hopes to accomplish by mid-2007. He is actually so bullish on the technology that he believes software will be the laggard, not hardware. "I do think RF Time of Flight is going to be a big deal and [will] give people the localization capability that delivers on the promise of RFID. But it will take creative people getting the applications right. The technology's almost ready."
Read the article from eWeek
