RFID stands for “Radio Frequency Identification”.
This refers to the possibility of uniquely identifying an object with the aid of a small electronic circuit.
This electronic circuit is now so small that it can even be integrated into stickers, paper, cartons, clothing buttons etc.
The electronic circuit, which is fixed to all objects which are to be identified, is generally called a TAG. Each TAG number is unique worldwide.
These TAGs are available in various designs for different tasks. For the user, significant differences arise on the basis of the following criteria, in particular:
The distance from which a TAG can be read with the aid of an RFID reading device may vary between a few centimetres and a few hundred metres, depending on the TAG.
TAGs function with different frequencies (125 kHz – 2.54 gHz).
The various frequencies react very differently to interference factors such as the presence of metal and water.
Simple RFID TAGs haves only one function: To transfer their globally unique ID number to the RFID reading device. More complex TAGs have memory built in, which can be written onto by an RFID read/write device, and subsequently retrieved. This makes it possible to store additional information in a TAG regarding the object to which it is fixed.
We differentiate between passive and active TAGs.
Passive TAGs have a short range, and therefore do not require a built-in battery. The lifespan for these TAGs is very long. As such TAGs have not been manufactured for long, there isn’t really any practical experience relating to their lifespan.
Active TAGs have a built-in battery, which restricts their lifespan to approx. five to ten years.
Der Wunsch der Logistiker sind TAGs mit einem Preis deutlich unter 1 Cent. Nur dann ist es wirtschaftlich sinnvoll, jede Milchtüte mit einem Tag zu versehen und so das Ausräumen des Einkaufswagens an der Kasse zu vermeiden.
Die Realität ist eine andere: passive TAGs kosten derzeit ca. 20 Cent bis 1 Euro, aktive TAGs ca. 15 bis 50 Euro pro Stück.
Damit kommen derzeit nur solche RFID-Anwendungen in Frage, bei denen o.g. TAG-Kosten nicht ins Gewicht fallen.
