Metro Group Says New Tag Helped It Meet Its RFID Goals

By Claire Swedberg

The German retailer is using Avery Dennison's AD-843 tag to track pallets loaded with food products, providing nearly 100 percent read rate.

After two years of employing radio frequency identification to track some pallets of goods it ships to its supermarkets and wholesale food stores, Metro Group has fully deployed the system at all of its food markets in Germany, and at least 89 in France. The retailer is using what it describes as a new, more effective ultrahigh-frequency (UHF) tag: the AD-843, from Avery Dennison. The inlay was developed specifically for Metro Group, though it is now being marketed to other customers who ship pallets with loads that can make RFID reads difficult—such as products containing liquid, or those packaged in metal cans.

Metro Group first began utilizing the AD-843 in January 2009. Thus far, says Gerd Wolfram, managing director of MGI Metro Group Information Technology, the company's IT services division, the new tag gives the company nearly 100 percent read rates despite being attached to pallets loaded with goods containing metal and fluids.

The German retailer began applying UHF Gen 2 tags to its pallets two years ago, using tags and interrogators from a variety of vendors (see Metro Fleshes Out its RFID Plans). "Since 2007, we've seen the quality of Gen 2 tags increasing," Wolfram says. As a result, he adds, Metro Group has seen improved read rates for tags attached to pallets loaded with products that include metal and liquid. "We are pretty close to 100 percent."

Vendors ship pallets loaded with cases of food and other goods to nine Metro Group distribution centers (DCs) in Germany. Those products are then stored prior to being packed on new pallets and shipped to Metro Group's Cash & Carry wholesale stores and Real supermarkets. Typically, when one of Metro's DCs receives an order from a store, employees pick the requested cases of goods and place them on mixed pallets to be shipped to the site. Those mixed pallets are tagged with one AD-843 tag, which is then encoded with a unique ID number.

As the pallets are loaded onto trucks, Sirit or Intermec RFID interrogators capture their tag ID numbers—reading them even in instances where a tag is obstructed by cases of goods—and send those ID numbers, along with a date and time stamp, to software running on Metro Group's server. The software, designed and integrated by MGI Metro Group Information Technology, includes a database of pallet RFID tag ID numbers linked to the bar-code serial numbers of the products loaded on those pallets, enabling the software to interpret the RFID data and track when a pallet was shipped.

When the pallet arrives at one of the company's 400 retail locations—whether Metro Cash & Carry stores in Germany and France, or Metro Real supermarkets in Germany—Sirit, Impinj or Intermec RFID readers installed at those locations' receiving docks again capture the ID number on each pallet's tag. The software is then updated to show that the pallets were delivered to the specific retailer.

In 2008, Metro Group tagged and tracked approximately 3 million pallets that were shipped from the DCs and bound for stores in Germany and France (see Metro Group, DHL to Roll Out RFID in France). However, the system still had some snags. Although the tags performed well, Wolfram says, their read rate was not as good as Metro Group would have liked, in large part because the UHF tags were difficult to read through the liquid and metal goods loaded on the tagged pallets.

One year ago, Metro tried Avery Dennison's commercially available AD-840 tag, which contains an NXP G2XL chip with 240 bits of EPC memory (with an option for 512 bits of additional user memory) and measures 3.8 inches (97 millimeters) long and 1.6 inches (41 millimeters) wide. Metro tested the tag's performance when used on pallets loaded with RF-unfriendly products (liquids, as well as metal containers), and confirmed that the 840—a narrow tag designed for airline baggage-tracking applications—provided a good read rate, according to Maggie Bidlingmaier, Avery Dennison's global director of sales and marketing RFID.

At Metro's request, Avery Dennison agreed to develop a new tag offering even greater performance. Metro chose the final inlay from design options provided by Avery Dennison, Bidlingmaier says. The resulting wide tag, the AD-843 (which measures 3.8 inches in width and 1.6 inches in length), contains an Impinj Monza 3 chip with 96 bits of memory and an antenna that's larger than that of the AD-840.

"The AD-843 is especially powerful on a broad variety of products," Bidlingmaier says. "It shows top performance on liquids, as well as in reflective, metallic environments, plus a superior basic performance for standard benign products. Although it was designed for this application, the AD-843 turned out to be a superior performer for a broad range of applications, due to its robustness and its performance near metal and near liquids." Consequently, she explains, Avery Dennison is now marketing the AD-843 to other end users.

According to Wolfram, Metro Group hopes to move the use of RFID further up its supply chain. "We have a strategy to start tagging pallets first," he says. "However, our next step is to use the same infrastructure for tagged cartons." How soon that tagging will begin has not yet been decided. In part, he states, "it depends on the interest of our suppliers."

Metro Group also sells commercial electronics at its Saturn and Media Markt stores, though these products and the pallets on which they are shipped are not yet being tagged. In 2007, the company's Galeria Kaufhof department store division launched a project involving the application of EPC tags to individual garments, as well as the use of RFID-enabled dressing rooms and displays and a smart mirror (see Metro Group's Galeria Kaufhof Launches UHF Item-Level Pilot).