Wireless Temperature Sensing with BST-Based Chipless Transponder Utilizing a Passive Phase Modulation Scheme

A passive wireless temperature sensor with identification capabilities based on a phase modulation scheme is discussed in this paper. The approach presented utilizes a pulse backscatter technique based on slow wave (metamaterial) transmission lines. The focus of the work are the material engineering for the temperature-sensitive element and the integration of this element into a passive phase modulation circuit and the entire sensor tag. The approach makes use of temperature-sensitive bariumstrontium-titanate thick film capacitances. The discussed principle has been experimentally verified with a prototype.