At Infosys, a 'Live Lab' RFID App Eases Parking

By Mary Catherine O'Connor

Feb. 22, 2007—Some 800 employees of information technology consulting and software services company Infosys Technologies can probably afford to snooze in the morning for just a few extra minutes, now that their employer has deployed an RFID-based parking system at its main campus in Bangalore, India. That's because cars no longer have to queue up outside the five-level parking garage at the start of each workday, explains Girish Ramachandra, delivery manager for Infosys RFID Solutions.

To enter the garage, each employee used to stop the vehicle, roll down a window and wave a personnel badge, which contains a low-frequency HID RFID transponder, in front of a reader near the gate. Once the system verified the employee ID encoded to the card, the gate would lift. During the morning rush, those steps led to backups that, on occasion, extended out to the street.

To alleviate this problem, and also to help employees find parking spaces once they entered the garage, Infosys installed a combination of ultrahigh-frequency RFID tags and magnetic sensors. Now, interrogators detect RFID tags embedded in windshield stickers attached to employee cars from as far as 3 meters in front of the gate. The readers send each tag's unique ID number to a middleware layer, which verifies that the employee associated with that ID has access to the garage. The middleware then sends a trigger for the gate to lift.

Each time a car drives onto one of the parking levels, a magnetic sensor embedded under the entrance sends a signal to middleware that is part of a device-management and decision-making engine designed by Infosys for the application, just as an identical sensor embedded under the pavement leading off the parking level does. The middleware keeps track of the number of cars driving onto and off each level. When a given floor reaches its capacity for cars, the middleware triggers a "level full" message to appear on displays positioned before each level entry.

"We looked at several options," explains Ramachandra, in regard to designing the system. While active (battery-powered) tags would have provided a long read range and good readability despite the metal in the car frames, such tags would also have broken the budget. "We needed an economically viable system," he says, "and active tags are too costly for this application." Active tags run from $15 to $20 apiece, and usually require readers that support a proprietary air-interface protocol. Passive UHF tags embedded into windshield stickers, on the other hand, cost around 30 cents each.