RFID systems offer significant benefits in applications such as supply chain management, enabling new business opportunities by providing efficient tracking solutions for production lines, warehouses, libraries and even livestock says Philips Semiconductors product manager for tags and labels Josef Preishuber-Pflügl
In the future RFID tags, containing integrated circuits, may come to completely replace current solutions such as bar codes. This rapidly growing trend is a result of the compelling logistical benefits of RFID – all that is needed now is to bring down the cost of RFID systems.
When introducing an RFID system into an application, setting up the infrastructure is the largest part of the cost, while the tags themselves represent only a small fraction. It is important for the system operator to carefully decide upon infrastructure – especially the readers – if the system is to be as cost-effective as possible.
For this reason, user groups and standardisation organisations define standards to offer both system integrators and users a common base that allows multiple silicon providers and tag manufacturers to provide interoperable products.
While the data processing and reader infrastructure represents a large fixed initial cost, the RFID tags are usually considered part of the running costs of the system. Accounting for a relatively small proportion of the initial cost, the cost of the tags becomes more significant as the application grows and larger quantities are needed.
As volumes grow, tags can be made cheaper through advances in the manufacturing processes used to make the ICs and integrate them into the tags.
While advances in manufacturing technology are important for cost reduction, the guarantee of multi-vendor support through standardisation is even more important.
EAN International and the Uniform Code Council together represent over a million users worldwide and are best known for the EAN.UCC system on bar codes. Since 1996, the organisations have been investigating the potential benefits of RFID in logistics and SCM.
In November this year EAN International and UCC will take ownership of the EPC network. Work done by the auto-ID Center at MIT and EAN.UCC will be used to launch a global multi-industry standard for the identification and networking of items using RFID.
Having such a standard developed for open systems allows multiple vendors to provide both tags and readers compatible with the EPC specifications and ensures broad product availability for end users. With multi-vendor scenarios creating competition on the market, it is an efficient approach to bringing down the cost of RFID tags.
In parallel to the activities on standards, silicon providers like Philips also work towards reducing costs in the manufacturing process. Today, vibration assembly is a well-known low-cost assembly method for discrete semi-conductors.
This assembly method, where vibration allows the silicon dies to fall into their appropriate place on the package, is well established and regularly used for assembling discrete semiconductors as used in mobile phone antenna circuitry. This method is an appropriately scalable assembly process for RFID to follow.
It remains cost-effective from low to high volume production – providing a strong foundation for the expected rapid growth in demand for RFID tags – and can function as a suitable add-on to standard pick and place methods as volumes increase and further cost reductions are required.
Choosing the right tag for the application can also help reduce costs. Most applications start with using read/write tag ICs like those in Philips’ I-Code family.
They operate at different RFID frequencies that allow contactless multiple reading and writing of data on the tag. This makes it very easy to maintain the legacy solution – in most cases barcode based – in parallel to RFID introduction. Most applications maintain the legacy data structure and leverage the RFID features.
Then, after some experience with the RFID installation, the focus moves towards additional cost reduction through optimisation and RFID becomes the sole means of product identification.
In supply chain applications, with a mixed population of returnable and disposable items, a selection of different tags is often used such as R/W tags for returnable items [to enable modification of data] and one-time programmable tags for disposable items.
The OTP products only implement the basic commands needed to get the data from the RFID tag, while the R/W products offer additional functionality by using the optional commands within ISO 18000.
OTP tags offer the same convenient contactless programming of the tag as R/W tags. As they are based on simpler manufacturing processes and, typically, have much smaller memory sizes than R/W tags, this helps keep costs down.
The use of standards as the basis for a competitive environment ensures that end users receive the best prices for RFID tags.
As volumes rise manufacturers can gain further leverage from scalable production methods.