The most common and efficient way to supervise cold chains while producing medication and groceries are RFID sensors. The RFID sensors that are currently used for such supervision are so called active transponder - equipped with a battery - to be able to send the data wirelessly to the target system. In the University in Zurich a team came up with a better idea, because they didn´t like the size and the complexity of the currently used sensors. They are currently working on a 0.8 mm big RFID sensor with its own charger that gets recharged when captured by a RFID Reader.
Charging via HF-Energy-Harvesting
This topic literally means "Harvesting Energy". In this case HF-Energy-Harvesting means power supply through RFID in the HF field when the RFID sensor is been read by a RFID Reader. The battery in the new, tiny RFID sensor is only 0.2 mm, all-electronics reports. With its wireless recharging, the annoying part of changing the batteries disappears, which currently takes place every three years. The supervision with these new RFID sensors with rechargeable batteries not only will be more environmentally friendly but also more safe and secure and the sensors cannot fail because they are out of charge.
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