Tego Introduces Radiation-Resistant EPC Tag

By Claire Swedberg

The Radion, capable of withstanding high levels of X-ray and gamma radiation, will be available in a variety of form factors, for use in the health-care, food, aerospace and defense industries.

RFID chip manufacturer Tego has released an EPC Gen 2 ultrahigh-frequency (UHF) tag that can withstand exposure to high levels of X-ray and gamma radiation, as well as other types of electromagnetic radiation, such as that found in the nuclear energy and defense sectors.

Most passive UHF tags that are exposed to high levels of gamma or X-ray radiation can suffer damage to their data, Tego reports. As such, the tags are not useable in applications that employ radiation for processes such as sanitization, as with medical implants, surgical kits, food containers and some defense industry applications in which radiation may be utilized. Tego has been developing a high-memory tag resistant to gamma rays for several years. It provided a 32-kilobyte gamma-resistant EPC Gen 2 (ISO-18000-6C) chip that was used by RCD Technology in its Sentry Tag for the aerospace industry. RCD continues to market the Sentry Tag, though it has not yet been used by a customer.

However, says Timothy Butler, Tego's president and CEO, the chip company is now offering a tag made with a lower-memory version of its 32-kilobyte chip, as a more immediate path to getting the tag onto the market. The tag, known as Radion, with 1.5 kilobits of memory, was developed to provide high-memory tags for tracking flyable aircraft parts.

Tego expects that the Radion's 1.5 kilobits of EPC and user memory will be a boon to supply chain, asset-management and logistics applications, as well as maintenance tracking. With the Radion tag, the company reports, users will be able to read and write tag data on the spot, without relying on back-end data systems, thereby significantly reducing the time and cost required for decision-making with assets and applications. One example cited by the company is the ability to view maintenance logs, configurations or other historical data at the point of read—a key benefit of Tego's extended-memory products.

The Radion tag is not susceptible to memory loss in the presence of radiation, as standard tags are, in part due to the way in which the memory is designed. "We optimized ours," Butler says. Standard tags have nonvolatile memory, but are still at risk of being destroyed or altered by radiation. That means both functionality—the ability to be read, and to be read accurately—and the memory on the tag itself are at risk, explains Bob Hamlin, Tego's CTO.

With the Radion tag, Hamlin says, the difference is in the circuit design, and in the firmware. By using a mechanical storage method, the data is less susceptible to damage in the presence of radiation, because the mechanical structure of the data storage can not be destroyed. Unlike all other EPC Gen 2 tags on the market, however, each unit of memory on the company's TegoChip is write-once—though, Hamlin notes, users could encode data to the tag 100 times or more without reaching the memory's limit. Therefore, he says, from a user's point of view, the memory functions in the same manner that re-writeable memory does. The Radion tag, Butler says, has a read range of 1.5 meters to 3 meters (4.9 feet to 9.8 feet), depending on the physical environment. The price will be similar to that of other high-memory tags, he adds—$3 to $5 apiece in high volumes, and $7 to $9 in low volumes.

Tego is presently working with RCD Technology and other partners that provide the inlays for the Radion tag, which Tego is marketing. For the past six months, the company has been testing the tag through a series of sterilization cycles, resulting in the total absorption of 100 kilograys (kGy) of gamma radiation (a chest X-ray, by comparison, results in a dose of approximately 0.5 kGy of radiation). According to Butler, the firm tested 36 million memory bits, or the equivalent of 380,000 tags, without suffering any malfunctions.

Tego worked with two companies in the life sciences and medical industry. At those firm's facilities, Tego tested 140 tags through three separate sterilization cycles, with the tags receiving a dosage of at least 25 kGy per cycle. All still functioned properly after the testing was completed, Hamlin says, adding that the testing is not yet finished. "Multiple passes is a great way to achieve a high confidence level," he states, so the company intends to continue testing the same tags through additional cycles.

The tag is the first of its kind, says Drew Nathanson, a research analyst at VDC Research. "I think there's a lot of potential with it," he asserts, due to the strong need for high-memory UHF passive tags that may be exposed to radiation.

In 2006, Advantapure announced a passive HF tag that it said could sustain radiation (see RFID Tag Built to Survive Gamma Rays). And last year, Smartrac made a similar announcement (see RFID News Roundup: Smartrac Launches Gamma Radiation-Proof RFID Tags).

Tego will exhibit the Radion tag next week at the RFID Journal LIVE! 2011 conference and exhibition, being held on Apr. 12-14, 2011, in Orlando, Fla. The company will have as many as 20 form factors to meet the needs of a variety of industries that could utilize the tag. For example, there will be one form factor for aerospace, while the food and medical-device sectors would require different sizes and dimensions. All 20 form factors should be commercially available by the end of the year, the firm reports.

Tego's chips and the Radion tag do not yet have EPCglobal certification, Hamlin says, though it has conducted EPC testing itself, and has verified the chip against about 12 standard readers. The company has yet to submit the chip used in the Radion tag for third-party compliance testing, he adds, stating, "We plan to pursue full certification this year."