RFID windshield tag drives cashless parking system  Parking
technology has finally caught up to our on-the-go culture: pay
without paying attention. Researchers have built a device that
does for parking lots what radio transponders do for highway
tolls. You park, it keeps track.  The near field communications
(NFC) system, dubbed Viatag, consists of 0.5 inch by 4-inch RFID
windshield tags, parking lot transceivers that read tags, and a
central database. The windshield tag signals the parking
transceiver as you're entering and exiting a parking lot. A
central database tallies your time in the lot and debits your
account accordingly.  The tag is unobtrusive compared with bulky
highway toll transponders. This is because it's a passive RFID
tag--no batteries. Instead it draws power through the air--from
radio waves sent by the transceivers.… Read more