This week, Aeroscout, the company formerly known as Bluesoft (famous around these parts for a system that locates lost children in Legoland) has announced a more active version of its system, which includes real-time location and active RFID location and passive location-tracking applications onto a single wireless infrastructure.

The addition of the "Exciter" component to AeroScout's Wi-Fi-based radio frequency identification (RFID) platform enables items to be tracked as they pass through a particular "choke point," such as a gate, doorway, or particular section of a shop floor, to help manage various processes or conserve an RFID tag's battery life, says Andris Berzins, vice president of marketing and business development.

Competitor WhereNet offers a similar capability with its WherePort II and Where Tag II RFID products.

Berzins describes a couple of scenarios where the combination of real-time and passive RFID on a combined network could be useful:

Tell your truckers where to go
Say you have a distribution centre with trucks arriving and checking in at a gate with a guard, who looks up the vehicle's particulars and then instructs the driver where to park and unload - a time-consuming process.

Instead, you could have a passive RFID Exciter (or Where Tag II) tag in the truck that switches on upon arrival and transmits the tag ID with gate information to a server, which matches it to information about the truck at hand in an application. The application then sends back display information directing the driver, thus eliminating the interaction time between guard and driver.

However, should the truck go missing outside the distribution yard, the RTLS component kicks in for location tracking.

Track carts when you need to
In a grocery store, you might want the RTLS tag on a shopping cart to transmit frequently for business intelligence purposes - to understand store traffic patterns and perhaps aid in merchandising and store layout decisions. However, when the cart heads for the parking lot where it might sit idle for a number of hours, you might wish the battery on the RFID tag to be turned off to preserve the life of the tag. So when the cart exits the door (a "choke point"), the tag could be switched off.

There are also applications for combined RTLS and passive RFID in healthcare, as equipment passes from one facility to another and ends up lost or even stolen, Berzins says.