RFID in automation
RFID stands for Radio Frequency Identification
RFID makes it possible to provide objects (mostly workpieces or workpiece carriers) with so-called transponders, so that not only can they be clearly identified, but also data can be exchanged with the control system - reading and writing. As a result, not only can data be recorded and stored during the machining process, but control decisions can also be made more flexibly than before. In contrast to the barcode, no visual contact is necessary and the workpiece can also be detected over a greater distance. This makes RFID systems an integral part of a "Smart Factory" or the basis for Industry 4.0.
The actual data carriers of an RFID system form the so-called transponders or RFID tags, which can be attached to the workpiece itself or on a workpiece carrier. You can distinguish between the so-called passive and active transponders. More on this later. In order to be able to access the data remotely, an RFID Read / Write unit is used. This Read/Write device can communicate with the RFID tag via an alternating electromagnetic field. Futhermore a computing unit, PC or PLC, can process this data and e.g. store in a cloud.  Transponder - data medium of the RFID; the term transponder is composed of "transmit" and "respond"
How can you classify RFID systems?
Meantime, this technology has advanced so far that the right RFID system can now be offered for most applications. This is just an attempt to give an overview of these different RFID systems: