Post Danmark to Tag Its Roll Cages

By Jonathan Collins

Apr. 20, 2006—In a project set for completion by the end of the year, Post Danmark—the Danish postal service—will tag all of the 25,000 roll cages at its facility. These wheeled containers are used to move mail around its mail-distribution network.

The mail carrier believes tagging its roll cages will help reduce the loss of such cages, as well as improve the security of mail during transport and track roll-cage usage. The carrier also expects to reduce supply chain inefficiencies and improve workflow. For the purpose of this project, Post Danmark plans to use semi-active RFID technology—battery-powered tags programmed to transmit only when requested. The carrier is already using semi-active tags to monitor its international mail operations. The decision to expand the use to roll cages has not been a speedy one.

Claus Jensen, Lyngsoe Systems

"We initially completed a trial of a few hundred tagged cages more than a year ago as a proof of concept," says Claus Jensen, area sales manager at Lyngsoe Systems.The Danish RFID company will supply the hardware and install the new RFID system at Post Danmark.

The initial trial deployment used Lyngsoe's semi-active tags and interrogators. "Post Danmark then looked for an alternative, passive RFID solution," Jensen recalls, "but they couldn't find one to meet their read-rate requirements. That's why the decision [to deploy Lyngsoe's semi-active system] took a year."

According to Lyngsoe, Post Danmark sought a passive-tag solution for roll cages. That way, if it ever adopted a passive-tag system to track letters, trays, parcels and other items, the carrier could use a single system to track both the mail and the cages. For cage-tracking, Post Danmark demanded the rate of successful read attempts be at least 98 percent—and as close to 100 as possible. Without such a high performance level, the system would not be able to provide sufficient data for load control, volume forecasting and tracking and tracing. According to Lyngsoe, the passive solution did not reach this target.

Post Danmark's failed effort involving passive tags stands in contrast to Finland Post's success in using passive tags to track its own roll cages. This past summer, Finland's national mail carrier tagged 200 of the 200,000 roll cages it uses to store and transport packages and letters. The 200 roll cages were fitted with passive 856 MHz UHF tags made with Philips Semiconductors' U-Code HSL chips (see Finland Post Finds RFID Can Deliver ROI). However, the two roll-cage types are not identical. Finland Post's cages have three closed metal sides (the fourth side is open), whereas Post Danmark's have all four closed.