The use of RFID systems in metallic environments is problematic. Either the transponder (tag) is located in a metallic environment, for example in a container, or it is attached directly to a metallic substrate. UHF transponders come up against physical limits that prevent reliable bulk reading, for example by forming standing waves. Inductive couplings (LF and HF) are also not suitable for parallel detection, since they also prevent bulk reading. Therefore, the Fraunhofer Institute for Microelectronic Circuits and Systems IMS in Duisburg is researching the next RFID generation together with partners. For this purpose, the SHF band (Super High Frequency) is used: Especially in the 5.8 GHz ISM band, it offers several advantages over UHF-based solutions due to the higher bandwidth of 150 MHz. Communication in the developed tag is based on the RFID standard in the UHF band ISO 18000-6 EPC Gen 2. An essential feature is the reliable reading of several tags by collision avoidance when several tags respond in parallel.
This solution was nominated for the Automation Award 2020 in the TECHNOLOGY category.