RFID is an acronym for Radio Frequency Identification. This technology allows embedding a small and usually very cheap (few pence) radio transmitters (called "RFID tag") into objects (like boxes, pallets, containers but also animals), which can send information when interrogated by a reader using radio signals (see structure of an RFID system).
This information can be as simple as just a number (like the one found in barcodes) called tag id, up to large and complex piece of data, and can be used to quickly and efficiently "keep track" of items as they go through the manufacture and the supply chain - please see the business improvements.
The biggest advantages of RFID compared to other AIDC technologies (such as barcodes) are:
- RFID does not require line of sight – radio waves travel through objects;
- RFID can support anticollision, i.e. the ability to read information from more than one tag at the same time;
- RFID tags can be writable, this means you can use radio waves not only to read the content of a tag, but also to modify its content;
- RFID tags ID can be globally unique, and the tag's memory can contain a considerable amount of data;
- RFID tags content can be password protected or even encrypted.
While this is a relatively old technology (it is based on concepts developed during the Second World War) it is only recently that it has found many of its applications, thanks to a substantial reduction in cost and a constant improvement to its accuracy.