Wireless Temperature Monitoring With Shape Memory Alloy-Based Antenna

• Published in: IEEE antennas and wireless propagation letters Vol. 20; no. 3; pp. 313 - 316
• Main Authors: Wang, Wei, Zeng, Wenxin, Sadeqi, Aydin, Sonkusale, Sameer
• Format: Journal Article
• Language: English
• Published: New York IEEE 01-03-2021; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antennas; Austenite; Data logging; Dipole antennas; Electronic devices; Frequency response; Impedance; Martensite; Sensors; Shape memory alloy (SMA); Shape memory alloys; Temperature measurement; Temperature profiles; temperature recording; temperature sensing; Temperature sensors
• ISSN: 1536-1225; 1548-5757
• DOI: 10.1109/LAWP.2020.3048884

Economical sensing and recording of temperature are important in the transportation and management of fragile goods such as medicine, fish/poultry, and other temperature-sensitive items. Existing approaches measure the entire temperature profile using electronic devices running on a continuous power source. This letter presents a simple, intelligent, and battery-free solution for capturing interesting temperature events using the natural thermo-mechanical state of a shape memory alloy (SMA). Our approach utilizes the temperature variation induced irreversible configuration of SMA, which provides a natural ability to capture the temperature history without the need for electronic data logging. In this letter, SMA is used to record the threshold temperature violation event. A prototype antenna is shown to monitor the temperature at 30 <inline-formula><tex-math notation="LaTeX">^\circ</tex-math></inline-formula>C with a <inline-formula><tex-math notation="LaTeX">\pm</tex-math></inline-formula>1 <inline-formula><tex-math notation="LaTeX">^\circ</tex-math></inline-formula>C error. A difference of 17 dB in frequency response was observed with and without temperature violation. Detailed design and experimental studies have been performed to validate the proposed approach.