RFID Packaging Primer

In the simplest terms an RFID packaging system consists of a tag (transponder) and a reader (interrogator).

The technology of RFID packaging deals with the remote collection of information stored on a tag using radio frequency communications. The information stored on the tag can range from as little as an identification number, to kilo-bytes of data written to and read from the tag, to dynamic information maintained on the tag, such as temperature histories. The information from the tag/reader combination is either presented to a human operator typically using a hand-held device with a alpha-numeric display or a host computer which automatically manages the information.

Frequency

Critical performance variables in an RFID packaging system involve the range at which communication can be maintained, the size of the information space contained on the tag, the rate at which the communication with the tag can take place, the physical size of the tag, the ability of the system to “simultaneously” communication with multiple tags, and the robustness of the communication with respect to interference due to material in the path between the reader and the tag. Several factors determine the level of performance that can be achieved in these variable. The factors include the legal/regulatory emission levels allowed in the country of use, whether or not a battery is included in the tag to assist its communication back to the reader, and the frequency of the RF carrier used to transport the information between the tag and the reader.

Over the course of decades of RFID package development, industry has evolved RFID packaging solutions that variously trade the regulatory constraints, the signal propagation characteristics of various RF carrier frequencies, and the economics of tag size and optional batteries. These solutions employ only a few RF frequencies around which the vast majority of RFID systems are fielded today. The RF frequencies include relatively narrow bands centered at: 125/134KHz or low frequency (LF) 13.56MHz or high frequency (HF) 433/869/915MHz or ultra-high frequency (UHF) 2.45/5.8GHz or micro-wave (uW).

These frequency values are commonly referred to the RFID packaging technology. Thus, tags and readers combinations are described as employing LF, HF, UHF, or uW technology.

Passive/Active Tags

Within any one technology there is a wide variety in tag performance reflecting semiconductor chip performance, tag antenna size and efficiency, and whether a battery is included in the tag. There are two broad classes of tags with respect to the source of energy used to power the tags: passive tags or those that receive their energy solely from the RF field supplied by the reader, or active tags that have a battery to boost the read range of the tag.

Read Range

In many cases there is a sharp delineation between the read range of two classes of tags employing passive technology, those that have a relatively short read range and those that have a relatively long read range, especially at LF and HE Like many radio systems, short range RFID systems tend to be less expensive and relatively easy to design and build. Long range RFID packaging systems tend to be more expensive and difficult to build. Typically, the range performance of RFID packagin systems is determined to a major extent by the reader, the power of the signal it radiates and the sensitivity of its receiver.

Anti-Collision

In many applications it is desirable to communicate with a tag when other similar tags are simultaneously visible to the reader. In the case of tagging pigs, it is unlikely two pigs will need to be in the read space at the same time. In the case of library books an important design feature is the ability to read and “check-out” multiple books as the same time. The ability of the tag/reader system to talk unambiguously with one tag at a time is determined by the anti-collision algorithm used to identify each tag and establish a communication session with the tag.

Tag/Reader Communication Protocols

How information is communicated to and from the tag has historically been determined by the original designer of the semiconductor device in the tag. These protocols vary widely in the ways the carrier is modulated, the data is encoded, read, write, verify commands are structured, how multiple tags are read without interfering with one another, and whether privacy or security services are provided. These varying protocols have relative advantages and disadvantages, depending upon the application being considered.

Standards

Over time RFID manufacturers and users have typically concluded that while there are advantages to having several communication protocols from which to choose for any application, there would at each frequency be an advantage to settling on one protocol, or at most a couple of protocols, which multiple suppliers could offer chips and readers.

The appearance of these standards is relatively recent and reflects the work of industry bodies including the UCC and the EAN, the International Standard Organization ISO, and national bodies like ANSI in the U.S. Many of these standards are new or are in the process of being defined and there is considerable uncertainty what their form will ultimately be.

Summary

The RFID industry today represents a dynamic attempt by manufacturers and users to build and deploy solutions reflecting trade-offs between a wide range of technical, political, and regulatory constraints. It is in this dynamic environment that SAMSys provides RFID readers which enable end-users, system integrators, and automatic data capture (ADC) equipment suppliers to make timely and safe decisions about how to employ RFID.

For more information on the RFID packaging, please contact:

Bar Code Specialties
12272 Monarch Street
Garden Grove, CA 92841
1-844-411-CODE

RFID Packaging For Wal-Mart

Do you do business with Wal-Mart?

Soon, all suppliers to Wal-Mart will be required to affix special radio frequency identification, or RFID tags onto all cases and pallets.

Many of the top suppliers are still trying to figure out all this out. How will these new tagging requirements affect them, as well as the effort necessary to meet the goal? Several leading suppliers acknowledge it will be a huge effort.

Once again contract packagers across the national may be called upon to assist in this tagging challenge. As these new scope of work requirements are really no different than changes in the marketplace during the 1980’s when Sol Price opened the first Price Club warehouse stores. Clients are asking for something a little different and until they can find or develop manufacturing systems to handle the problem contract packagers may have the least cost, most effective, and quickest solution to manage the opportunity.

Wal-Mart has identified several key advantages to having these RFID tags used…

• Better tracking and moving of inventory
• Faster receiving and shipping
• Improved quality inspection
• Fewer out-of-stock items resulting in improved shopper satisfaction
• Greater predictability in product demand
• Better value for shoppers as efficiencies occur
• The right products, in the right stores, at the right prices

The RFID tags are not without problems today and Wal-Mart has advised their 20,000 suppliers that they will work with them to address and potential problems:

• Tags cost thirty cents today and Wal-Mart hopes that the price will be driven down to the $0.10 range as more and more suppliers purchase them
• Lack of agreed upon industry standard
• Smart Tag technology is far from perfect, as about 20% of today’s tags do not function properly
• Physical limitations of tags still exist, as tags can not be read through liquids or metals
• Nylon conveyor belts and other radio frequencies can disrupt the tags transmissions in warehouses

Wal-Mart is pushing the envelope of today’s tag technology before this technology is mature. Suppliers too are challenged by the equipping of warehouses and trucks with devices to read data from the tags. These devices will have to have integrated readers that can return real-time information to corporate computer networks. This means that there will be additional costs related to hiring tech consultants and additional hardware.

Wal-Mart is asking nothing more creative than Sol Price did when he started selling multi-packs of product or larger size containers. These companies have pushed the edge of the envelope out for the whole industry.

Contract packagers were there providing special handling and multi-pack services for warehouse club stores then, and many within our industry will be there this year for Wal-Mart’s RFID tags special handling services as well. Finding solutions for uncharted new packaging technology is what many contract packagers, including Aaron Thomas Company, do best.

CNBC reported through MSN Money recently wrote, “Do you speak RFID? Get used to it. This is the tech acronym most likely to get big media play in 2004. It stands fro Radio Frequency Identification Tracking, and with Wal-Mart, the Pentagon, Visa, and American Express behind it, the technology will generate a lot of excitement.” Sounds a lot like what we read about Y2K a few years back.

Four public companies were identified to watch: Zebra Technologies and Printronix as they are both bar-code printer makers that are expanding into RFID printing, Checkpoint Systems a maker of integrated systems for retail security systems, and Symbol Technology a maker of the wireless networks needed to collect data from RFID tags.