RFID technology provider Impinj has developed a system that it says can encode numerous ultrahigh-frequency (UHF) EPC Gen 2 tags after they’ve been affixed to items and packed into cases. The system is designed to help pharmaceutical and other companies that need to tag individual items.
If companies want to encode tags in labels individually as they are automatically affixed to prescription bottles, blister packs and other product packages on lines during the packaging process, they must retrofit the RFID-encoding system into existing processes. Such a system, however, can slow line speeds considerably. Impinj’s system, on the other hand, encodes the tags of products after they’ve been labeled and aggregated into bundles or cases. The product, which the company has not yet officially named but refers to as a Commissioning Station, can be set up on a conveyor belt at the end of a single packaging line, or at the end of multiple packaging lines converging at the station.
“This product is the outcome of work we’ve done with some pharmaceutical companies that were implementing RFID traditionally in-line,” says Impinj VP Vince Moretti. “They were getting the tags [encoded] but were seeing how difficult it is to do it that way, how long it takes and how invasive it is to their packaging lines.”
Some pharmaceutical companies, Moretti says, are currently implementing RFID with two-dimensional serialized bar codes. “When they do that, they are driven to an in-line solution,” he explains. “Two-D can be encoded only in-line, and RFID must also be encoded in-line to assure that the bar-code and RFID serial numbers match. Pharma companies did not know that end-of-line encoding could be done reliably. There were the early myths about problems operating with metal [blister packs] and liquids. Near-field UHF addressed these issues.”
The Commissioning Station is designed to work specifically with RFID tags and labels made with Impinj’s Monza EPC Gen 2 chip, and will consist of two Impinj near-field RFID antennas and an Impinj Speedway RFID interrogator running specialized software designed to eliminate network latencies that could slow encoding functions.
“On a packaging line, there are many devices [cameras, printers, RFID readers and computers] that are connected via a private network,” Moretti says. “When labels and bottles are moving at hundreds of items per minute, there is only tens of milliseconds of time to complete operations. If the network is busy transferring data from one device, or the computer is busy decoding a poor quality 2-D code, another device may not get serviced in a timely manner and the tag will be gone. We have put software on the reader to minimize the low-level network traffic to accomplish RFID operations such as read, write and lock. The reader CPU can also work independently from the computer on low-level tag interactions. This virtually eliminates the possibility of missing tags.”
Encoding is a much more complex operation than reading, Moretti explains. “It takes more time and requires higher power to be delivered to the tag. You need sensitive tags, a good reader and the right algorithm to encode reliably, especially on a large population of tags. Impinj has tackled these challenges over the last year using our Monza silicon, Speedway reader and special pharma firmware that runs on the reader.”
The Commissioning Station will also include an RFID printer-encoder. According to Moretti, Impinj will decide on a specific printer-encoder for the product prior to the product’s official launch, which is expected sometime in the second quarter of 2008.
Here’s how the station will work: As a packed case of products approaches the station, the RFID printer-encoder will print and encode an Electronic Product Code (EPC) to an RFID label and apply it to a case. The case will then move between the two antennas, and the Speedway interrogator will begin encoding a unique EPC to the RFID tag attached to each item within the case. The specialized software running on the interrogator will track the encoding progress by counting the tags successfully encoded, and comparing that total with the number of tags it is supposed to encode.
“The system will know how many items are shipping in a case,” Moretti says. “For example, it’ll know that the case holds 72 items, and that it needs to encode 72 tags. So if it is able to encode only 71, the system will know there’s a problem.” In the event that a problem is discovered, the system will send the case out through a rejection chute to a rework station. The software in the Speedway reader will also be able to control the conveyor belt speed, he adds, “so if the encoding of the tags slows, it’ll slow the belt down in order to catch all the tags.”
Impinj debuted its Commissioning Station earlier this month at the Track & Trace Health Care Industry Adoption Summit, sponsored by the National Association of Chain Drug Stores (NACDS) and the Healthcare Distribution Management Association (HDMA). During the demonstration, the station successfully encoded between 500 and 800 tags per minute. An in-line system can encode only about 250 UHF Gen 2 item tags per minute, Moretti notes, adding that for high-frequency (HF) RFID tags, the encoding speed is about 120 items per minute.
“Nobody wants to slow their line to accommodate serialization, 2-D or RFID,” he says. “Speed is going to be a problem for in-line systems. Mass serialization at the end of the line will always be the fastest method of encoding.” The Impinj demo successfully encoded item tags inside cases containing 48 bottles with tags embedded on the bottoms of the bottles, as well as another 48 with labels affixed to their sides. It also encoded item tags in cases containing 72 closely packed blister packs and 72 bottles of liquids.