U.S. scientists say they've designed a system capable of simultaneously measuring and testing hundreds of radio frequency identification tags.

The new system allows the measurement of the signal strength of tags hidden behind other tags, said Georgia Institute of Technology Assistant Professor Gregory Durgin, who led the research.

RFID tags are used for applications that include inventory management, toll collection and airport luggage security.

The tag absorbs some radio frequency energy from a reader signal and reflects it as a return signal, delivering information from the tag's memory.

If several RFID tags are in the vicinity of a reader, the reader usually communicates with the tag transmitting the most powerful signal first and then puts it to sleep to prevent it from transmitting repeatedly. Then the reader moves to the next most powerful signal. This process can be very time-consuming.

We designed a really inexpensive, simple anti-collision system that transmits multiple unique signals back to us simultaneously without this complicated back and forth process, said Durgin.

The research that included graduate students Anil Rohatgi and Joshua Griffin was presented in Las Vegas last month during the IEEE International Conference on RFID. (c) UPI