At Wayne Memorial, RFID Pays for Itself

The readers pass along the data collected from the tags to collectors, which manage multiple readers, explains Stephen Jackson, RadarFind's CTO and one of three company founders, alongside CFO and COO Bobby Bahram, and chief medical officer Vincent N. Carrasco. The readers can communicate to the collectors—RadarFind suggests installing one collector per floor—using either the 902-928 MHz band or the hospital's power lines, by sending special data signals over the power wiring. The collectors then pass the data, via a local area network, onto a RadarFind server.

RadarFind has opted not to employ tags and readers using the 802.11 Wi-Fi 2.4 GHz communications protocol, which a number of other RTLS providers are currently leveraging. The company says this is because hospitals need to reserve their Wi-Fi networks for other applications.

"We spent an enormous amount of time really looking at what hospitals need, looking at the type of technologies, type of frequencies and even how hospitals will evolve in the future," Carrasco says. "I would not take lightly the fact that we are purposely avoiding the 802.11 approach because of the data needs of hospitals. The potential of using a locating or tracking system that leverages 802.11 is that these systems can actually disrupt other systems because of the load of tracking data is going to increase."

In a typical installation, each patient's room will have one interrogator. The read range for each reader is programmable, Jackson says, from about 3 feet to about 150 feet, Jackson says. In a larger area, such as a cafeteria, a hospital could decide to break the area into zones, then place readers corresponding to the number of zones. For example, a cafeteria could be broken into four quadrants and, thus, have four readers.

"The system is modeled in very much the same way that aircraft are tracked," Jackson says. "At commercial airports, there is a big antenna that spins around to monitor where aircraft are. The antenna sends out a signal as it spins around, and as the signal hits the airplane, there's a box in the airplane and that box responds, 'I'm aircraft such and such; I'm flying at this air speed, at this elevation.' Instead of one big gigantic reader, we have hundreds of these that are electronically scanning the room."