Battery-free RFID moisture sensor tag

Paul Boughton

The HYDRO from Farsens SL is a new battery-free RFID tag featuring a humidity sensor. These sensors are compatible with commercial EPC C1G2 compliant readers. Multiple HYDRO tags can be used in a short area and the reader will receive specific ID numbers with the associated humidity level data.

The HYDRO has a 96 bits EPC number, a 32 bit TID and a password protected Kill command. Built in a PCB format, it is available in different sizes. The read range is up to 1.5 metres and the operating temperatures are from -30°C to +85°C (-22°F to 185°F).

HYDRO tags can be embedded in different materials and read wirelessly from the outside for an effective moisture level monitoring. These tags allow for applications such as irrigation automation (activating irrigation just in the areas that require such activity) or detection of liquids in areas/items that should be completely dry.

Farsens designs and manufactures full passive RFID sensor solutions. Their proprietary UHF RFID IC allows Farsens to develop long range solutions for asset tracking – via the unique ID – and monitoring – via the attached sensor – without the need of any battery on the tag.

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