Enabling smart tracking for the supply chain and Industry 4.0 with RFID
Do you know where your product has been and where it is going right now? This is the challenge that many manufacturers and logistics companies face in the management of their supply chains. As more functions are outsourced and supply chains become more complex, traditional approaches to keeping track of product movements are unable to keep pace.
In food and medicine supply chains understanding how products are transported is critical. If the temperature rises beyond a safe threshold at some point during transportation, the food may no longer be safe to eat at its destination and medicines become ineffective. During transport, goods will often change hands several times. The producer can keep track of the temperature of their pallets while they hold them. But when handed over there are no guarantees their guidelines will be followed. Spot checks with data loggers at points on the product’s journey can only provide a snapshot. This is where RFID technology is beginning to make a difference.
An RFID tag that integrates a temperature sensor can perform regular measurements to show that the supply chain requirements have been met and that the product is still safe. When interrogated by an RFID reader at ingress and egress points along the way, the tags provide data on how the temperature changed during the journey.
Within the manufacturing plant itself, RFID provides one of the technologies that will drive the Industry 4.0 revolution. A key advantage of RFID technology in the manufacturing environment is that it enables mass customisation. Everything from the morning cereal to motorbikes can be tuned to a customer’s preference. If you want more raisins in your muesli or a specific paint job, manufacturers are now beginning to let you do that as part of the ordering process. Without a technology like RFID, it is extremely difficult to support such a level of customisation. The manufacturer would need to synchronise multiple systems to make sure that a specific product moving through a factory receives the right mix of ingredients or treatments. With RFID tracking, the product itself can tell the machines and operators what it needs.
Typically, a product carrier contains the RFID tag into which is programmed a unique identifier at minimum. Potentially, the tag can store many other data items that may be used by machinery to optimise the product’s journey through the plant. In the case of custom cereal, when the carrier arrives at the raisin dispenser, the unit knows how much to add and mix. If the dispenser is unable to comply, it can write the error to the tag so that the product is not sent out incomplete. This is where barcodes, which have been used in the past to support product customisation, are not as effective.
There are a number of core requirements for industrial and supply chain RFID tags. The tag needs to be robust, offer consistent performance and be easy to apply to a product. There are standards that determine the level of performance needed from an RFID tag. The key standard for industrial applications is EPC Global Ultra High Frequency Gen 2. It can use a smaller antenna than the low- and high-frequency RFID technologies and offers a communications range from 0.5 to 8m depending on antenna design. The antenna structure is crucial to performance. Fortunately for OEMs and integrators, the high frequency of Gen2 communications makes it possible to incorporate the antenna in the same convenient package as the RFID interface and controller IC. This can make the solution much more robust than with a PCB-printed antenna and chip.
An example of a high integration Gen2 RFID device is Murata’s MAGICSTRAP (right). It
contains a complete interface IC integrated with matching circuitry and antenna inside a
low temperature co-fired ceramic (LTCC) and resin substrate. By providing the RF
matching internally, the MAGICSTRAP device optimises power transfer between the IC
and the customer antenna. The controller ICs can be multiple-sourced for maximum
flexibility but with the same customer’s own preferred antenna pattern. The design uses
inductive coupling between the antenna and the strap. In contrast to traditional RFID IC
packages that need to be soldered to the PCB to provide an electrical connection, the
MAGICSTRAP package needs only a mechanical connection, so that non-conductive
epoxy can be used in place of solder.
Thanks to its design and attachment method, the MAGICSTRAP can withstand a 2kV
ESD pulse. The tag also offers full-band impedance matching. This allows a single device
to operate from 850MHz to 960MHz frequency covering all the recognised UHF bands
used for RFID to support fully global operation.
Abracon provides a further range of package options based on ceramic packages and the choice of RFID ICs from leading providers Alien, Impinj and NXP. Abracon provides a number of standard designs to suit different supply chain RFID requirements supporting attachment to the product casing directly rather than a PCB. Tags can be attached directly to metal or embedded in the product’s surface, allowing maximum design flexibility.
Custom design options for the tag packages allow the integration of other devices alongside the RFID circuitry, supporting the inclusion of temperature sensors, additional memory and independent power sources for regular measurements. If you have any questions about RFID tag technology, or you need some advice on your application design, get in touch with our technical specialists by visiting the Ask an Expert page or clicking the button to the right of this post.