New Active RFID System Strives to Eliminate the 'Overhead'

According to Fenson, the U.S. Army's Armament Research, Development and Engineering Center (ARDEC) is testing the Roll-Call system in an RF-hostile environment containing the quantity of metal and RF interference that would make other RFID technology unreliable. For the ARDEC test, he says, InPoint deployed the system in an area of approximately 1,000 square feet, with tags buried among items with very high metal content that were densely packed on pallets. Six separate hubs, he says—each with multiple reader modules, and sending data to a central server—allowed the system to perform extremely well. "Pallets were moved around within the area with forklifts," Fenson states, "and at no time did any tag become invisible to the system." The data is displayed on a monitor attached to a hub in real time, with a picture of the tagged item, as well as location and condition information, displayed continuously.

InPoint has partnered with WinLab, at Rutgers University, to develop the system for the health-care industry as well, using it to tag medical records, equipment and patients. (InPoint's co-founder, Rich Howard, is one of WinLab's visiting professors.) When comparing Roll-Call with any other active RFID solution currently on the market, Fenson says, "the main advantage is [the] size and price" of InPoint's tags.

The prototype reader module contains a short wire antenna and a small circuit board that plugs into a computer's USB port.

Both health-care companies testing the system have asked to remain unnamed. The function of identifying the movement of, or around, a tag can be useful in many industries, Fenson says—and in this case, it can be accomplished without motion sensors. In a hospital, for example, the system can determine the amount of activity there has been around a specific patient, even if those administering to that individual lack tags, thus indicating he or she is receiving some assistance.

The movement-detecting function can also provide security alerts in, for example, a retail application, identifying the presence of someone in a location, such as a storage room, at a time when people are not permitted (the individual would need to be between the tag and the reader, and within 20 feet of the tag). This is accomplished by detecting a change in the tag's RF signature, or by identifying how often a product is picked up and placed back on a store shelf. While the tags are still too large for tracking most individual items of jewelry , they can be used on cartons to track the location of goods within a supply chain, as well as to track work in progress on some jewelry.

The system also supports sensor data, though there have not been any pilots of a sensor used with the Roll-Call hardware. A tag with an integrated sensor would have a reduced battery life (according to InPoint, the battery of a tag without a sensor, beaconing every two seconds, is expected to last for up to five years), and could also suffer some reduction in reception by the reader due to the larger packet payload. However, Fenson adds, "Because sensor data does not typically require 100 percent reliable packet reception every second, that overall effect should be minimal."