Issue #26 | April 28, 2005
My team is on a mission to conquer the world. That's right. We're working on a project right now that tests the limits of how well RFID technology operates in a global supply chain. First, let's talk differences...The frequency range of operation in Europe is 865.6 - 867.6 MHz, whereas in North America it is 902 - 928 MHz. Also, Europe has greater limitations on RF power, channels, and bandwidth. But the good news is that a new standard (ETSI EN 302-208) allows devices to use more power, bandwidth, and channels than the older standard. Make sure any EPC-compliant, UHF readers you plan to use in Europe support this new standard.
All devices should carry a 'CE Mark' that shows compliance with standards used in Europe. A reader that uses only the North American specifications cannot be used in Europe without a site license. Finally, none of the North American readers I've seen have power supplies that will operate unless you use a power converter. You simply won't be able to plug the Yankee version into any of the European electrical sockets. It's a rookie mistake.
Now comes the toughest hurdle to clear: tags. Most antenna patterns on tags are designed to perform best within a specific frequency range. This means there are tags optimally tuned for European frequencies and tags tuned for North American frequencies.
For our project, the requirements include an EPC global Class 1 tag that achieves a 3-meter read distance with minimal orientation sensitivity. As we set out to conquer the world, we compared two tags:
- Tag A is designed for North American use and has an antenna designed for optimal performance when operating with readers using 902 - 928 MHz. Let's call this the "NA"
- Tag B is designed for European use and has an antenna designed for optimal performance when operating with readers using 865 - 868 MHz. We'll name this the "Euro Tag."
Both
NA Tag and
Euro Tag worked with our North American and European Class 1 readers. Great, but you're looking for optimal performance, not just OK. So as you would expect,
NA Tag does not perform as well with European readers as it does with the North American readers. Similarly,
Euro Tag works better with European readers.
So which tag do you use if your process requires RFID tags to be affixed to products in Europe that are shipped to North America?
Here's a solution to consider:
The most challenging read in Europe is the outbound read point. The tag is moving at forklift speed and can be a couple meters from the antenna. The goal at this point is to verify a pallet is being loaded into the correct truck. Since
Euro Tag performs better in Europe at greater distances, because the tag is specifically designed for the region, it serves as a good pallet tag.
NA Tags can be affixed to the cases since it is important that they're read on the conveyance systems after the pallet is broken-down in North America. It's not necessary to verify all the cases on the pallet during the outbound load process in Europe. We found that
Euro Tags still work respectably well with the North American readers so they will serve the inbound operation.
This solution does require a printer / RFID encoder that supports both tag-types as well.
I know what you're thinking, "But Lou, we manufacture products in Asia. There are even more differences when you consider countries in Asia."
Never fear. Our engineers are currently researching a third option. There are some new tags on the market that have antenna patterns designed for operation in the entire UHF frequency range: 860 - 960 MHz. I don't expect them to perform as well in Europe as Euro Tag or as well in North America as NA Tag, but they might be the best option if you have tags moving around the globe.
Happy travels.
Written by Louis Sirico
Copyright ? 2005 Louis Sirico
