All that hype surrounding radio-frequency identification (RFID), particularly those predictions for gargantuan growth in the retail supply chain, seems to have simmered down. Though it's bounced around for more
than 20 years and has the support of industry consortium EPCglobal, Electronic Product Code (EPC)
RFID tagging still waits to become the next big thing.
While implementation of the EPCglobal Gen 2 standard for supply-chain tagging has rolled out much more
slowly than many analysts predicted, the program does continue to push forward. Before long, RFID carton
and pallet tagging will join the dozens of other established RFID applications—from toll transponders to animal
tags—that track and identify everyday items without line of sight and tie the physical world to the IT realm.
Despite its snail-like progression, some heat remains behind the Gen 2 hype. The standard has united the tracking demands
of major retailers like Target and Wal-Mart with the packaging initiatives of consumer-goods manufacturers. More importantly, EPC was the first major initiative to move RFID beyond its traditional closed-loop paradigm: Often, all parts of the
system come from the same supplier, or at least they're precisely tuned for a given application. While such closed-loop systems work well, they aren't really relevant in the toolbox of electronic designers—except for those who have directly been
designing the RFID systems. And now, that's starting to change.
With a combination of open standards and a potential ubiquity of low-cost readers and tagged goods, RFID is moving away
from proprietary applications toward a more fluid future. Readers and tags will be embedded inside cell phones, laptops, and
other electronic devices. As an electronic designer, you may soon find yourself designing RFID into your next product.
PAIRING UP
One key driver in this new wave of applications is the use of RFID for "pairing," or automatically identifying items that need to be coupled. These items can include electronics peripherals establishing communications or consumable components that need to be correctly matched or controlled.
EM Microelectronic, the semiconductor company of the Swatch Group, has implemented numerous projects where physical objects are logically bound via RFID. One example involves "smart refills" for electrical appliances with replaceable
parts, such as electric toothbrush heads. Another is inkjet print cartridges that communicate their identity to a printer, which
adapts its performance accordingly.
EM president Mougahed Darwish says that in pairing applications, an electronic device integrates an RFID reader chip,
and the corresponding disposable or refill part integrates a transponder chip. The transponder operates as a configurable
EEPROM, and the "host" device can then adapt its behavior according to the parameters that are communicated.
The miniaturization,
low power, and new
capabilities of the latest
RFID reader ICs operating at 13.56 MHz make it
easier for systems designers to develop embedded
RFID applications,
according to Johnsy
Varghese, manager of
high-frequency reader
products at Texas Instruments.
The newest RF chips feature more functionality, such as an integrated
analog front end,
encoders/decoders, filters,
voltage regulators, variable gain settings, automatic gain control (AGC), and available output supply and clock for external circuitry. These features reduce overall system complexity, bill of materials (BOM), and the need for additional software. Furthermore, smaller RF chip packages about
the size of a quarter enable smaller system designs that expand the realm of
products for embedded RFID.
Startup company SkyeTek focuses
on low-cost embedded tag readers
that can work with standards-based
tags from any supplier. Having trademarked the term "tagnostic," SkyeTek
CEO Rob Balgley says RFID readers
have traditionally been designed for given markets, like the supply chain, and have been complex and expensive.
SkyeTek's goal is a common RFID architecture,
creating a commonality
around frequency protocol
and choice of tags. "We
make it a lot easier for
somebody to make different design decisions. They
don't have to get locked
into a particular frequency
or a particular protocol or
even a particular tag,
because we are pretty agonistic with regard to all
three of those," Balgley
says.
The company's HF and UHF products have the same mechanical, electrical, and software interfaces—even the
same pin-outs. At the last minute, then,
the designer can decide between UHF
and HF. "Or, if you've got a whole family of products and you want to go in
both directions, your inventory and
stock is simplified," he says ().
SkyeTek's goal is the least expensive
hardware platform with the greatest amount of functionality and performance in the software. When designing
RFID for embedded systems, Balgley
says, it's important to keep BOM cost
low. "You don't want to hand somebody
a BOM with a lot of expensive parts,
high-end amplifiers, and parts like circulators, which, in and of themselves, can
be $100 to $200," he says.
The M9 UHF SkyeModule uses low-cost cell-phone components. The UHF
board costs $200, a price
Balgley says is 50% lower
than competitive modules,
while offering a 3-m read
range at 20 or 30 tags per
second. SkyeTek also licenses
its modules, driving costs
lower and enhancing the level of integration.
The ease of embedding
RFID technology is opening
new markets, and SkyeTek
foresees traditional RFID
applications like inventory
management and access
control converging into one
market. "There won't be
this fragmented, nonconsolidated view of RFID. When
there's one big market, that's
where things get interesting in terms of being able to
scale revenue and innovation," says Balgley.