Chipless RFID Temperature Memory and Multiparameter Sensor

This chapter presents a chipless radio‐frequency identification (RFID) memory sensor and multiparameter sensor development in two phases. It first discusses the theory of temperature threshold detection and memory material characteristics. The chapter then presents design of a single electric inductive‐capacitive (ELC) resonator loaded with memory material. Next, detailed experimentation is carried out for a highly compact chipless RFID memory sensor. Multiple parameter sensing enables a single chipless tag with a distinct ID to sense a number of physical parameters independently. Experimentation on humidity sensing and temperature threshold violation was performed in two steps. In the first step, humidity variation before temperature threshold violation was investigated. In the second step, humidity sensing is examined after the temperature exceeded the threshold. Finally, the chapter discusses the effect of temperature and humidity on each smart material to explain the lower sensitivity of polyvinyl alcohol (PVA) in high temperature conditions.