The possibilities of passive UHF RFID textile tags as comfortable wearable sweat rate sensors

Sweat rate measurements can be used for healthcare purposes as well as for helping in exercising. In this paper, the suitability of passive UHF (ultra high frequency) RFID (radiofrequency identification) technology for sweat rate sensing is investigated. The technology has a great potential in wearable, comfortable, and wireless sweat sensing systems, although it is not originally used for sensing purposes. Two types of textile sensing tag prototypes are presented, their performance is evaluated by wireless measurements, and the prospects and concerns of these are discussed in this paper. The achieved results indicate high potential of textile RFID tags in perspiration sensing.