A lot has been written lately about the use of smart RFID (Radio Frequency Identification) labels on pallets, packages and items for real-time, accurate data tracking. The evolution of warehouse management demands an efficient, low-cost and error free means of keeping track of fast moving supply chain goods.

An RFID label is just a plain paper label with some kind of RFID tag on it – Right?

The application of using smart labels on packaged goods has been considered for some time to increase the efficiency of tracking within the supply chain. Radio frequency ID labels have been around for many years in various forms and mostly used in access control, security and financial applications. The technology utilized was most likely proprietary to their supplier and no open systems had existed. Most of these labels, and sometime cards, used passive radio frequency identification, ”RFID”, techniques in the frequency range of 125kHz to 135kHz. These cards and labels were considerably thicker than most common labels and cards, much more expensive, had limited memory space and could only be read one at a time.

During the past few years numerous standards have emerged and are currently being adopted by the RFID transponder manufacturers. ISO 15693 for “vicinity” labels and cards, recommend 13.56 MHz as its carrier frequency. These standards feature a thinner foil inlet, higher memory space availability and allow numerous labels in the field to be read almost simultaneously using anti-collision, bit masking and time slot protocols.

ISO 15693 vicinity labels offer a maximum usable range of out to 28 inches from a single antenna or as much as 4 feet using multiple antenna elements and a high performance reader system.

RFID Inlay
The manufacture of the label starts with the “inlay” or “foil” which contains the metallic antenna loop, silicon chip and associated components. Dynasys specializes in supporting Texas Instruments HF-I Tag-It inlays. These 13.56 MHz inlays meet ISO 15693 specifications and come in various sizes.

Dynasys provides labels, laminated with various inlay sizes:

• 22.5mm x 38mm - Miniature Rectangle
• 35mm x 65mm - Access Control Rectangle
• 45mm x 45mm - Square
• 45mm x 76mm - Large Rectangle

High Performance Cards
Getting maximum range from an ISO 15693 vicinity label, referred to as an “ISO” label for short, requires the proper integration of RFID reader, RFID antenna system and choice of label inlay.

In order to obtain optimum range from a passive RFID label the largest inlay size typically offers the best range. The magnetic flux energy from the radio field of the reader induces currents in the conductors of the inlay. Typically, the larger the loop aperture of the inlay’s antenna, the more energy that is captured and usable by the tag.

The relative angle that the card is presented to the reader antenna is a major factor in the available coupling. Antenna systems can be designed for parallel or perpendicular coupling to the label. If the label presentation angle is random, every effort should be made to capture energy at various angles and positions in the field.

Consideration should be given whether the label will be used in a holder, mounted vertical or horizontal. Also, proximity to anything metallic may cause significant degradation in performance range.

Anti-collision protocols will allow multiple labels to be detected within a common field. Just how well multiple labels are handled is a function of the reader’s intelligence and the antenna’s field pattern.

Making the Right Choices
Choosing the proper components for an RFID system is far from a trivial undertaking. Many options exist for selecting the reader, antenna system, and reader software as well as choosing the optimum compatible label components.

There are numerous places to obtain technical information and get some familiarity on RFID technology. This site is a good start. We also offer numerous get-acquainted RFID kits in case you want to get some hands-on experience.

Dynasys engineers are expert in RFID technology and are available to you to answer any questions you may have. We will help you to design an RFID system that will work best for your application. Texas Instruments has selected Dynasys, and only Dynasys, to represent and support their RFID product line in the United States. We are proud of this achievement and continue to earn this honor by offering you the best support possible.

Give us a call!