Unlike with optical systems, an RFID transmission works without a line of sight via an air interface. A reader transmits electromagnetic waves, thereby generating an electromagnetic energy field and supplying the transponder with energy. The individualized data or numbers stored in the memory of the RFID transponder can be read out and/or modified.
While reading/writing, the reader’s software controls the actual process. In addition, the system uses RFID middleware with interfaces to ERP systems and databases.
An RFID system consists of the following components:
- Transponder (tag/smart label) with data memory and antenna
- Read/write unit (reader) with antenna
- Host/SPS with data processing software
An RFID transponder basically consists of a chip (storage), an antenna (transmitting and receiving) as well as a substrate material. The transponder may be complemented (for example) by an additional cover film or an adhesive coating for fastening.
The main functional component of an RFID transponder is the chip. The required read/write speed, encryption, data volume to be stored and other criteria determine the selection and dimensioning of the chip.
Size, shape and frequency of the antenna influence the range of the RFID system.
An inlay is the simplest version of an RFID transponder. It consists of a substrate film onto which the chip and antenna are combined. Inlays can be converted into labels or hardtags.
Version: RFID label or RFID tag
Self-adhesive RFID labels or tags integrate an inlay into a label format. The substrate material is provided with an adhesive coating to ensure the desired adhesion. An additional cover coating is applied on top of the inlay. This coating can be printed with additional information and/or design elements such as logos and inscriptions by digital printing. Many applications use RFID labels in combination with barcode solutions.
Version: casting with PU resin
Another option is casting the inlay into a PU resin coating. Due to the self-healing and pressure-compensating surface RFID inlays withstand even extremely high loads.