Toward the Optimal Antenna-Based Wireless Sensing Strategy: An Ice Sensing Case Study

• Published in: IEEE Open Journal of Antennas and Propagation Vol. 3; pp. 687 - 699
• Main Authors: Wagih, Mahmoud, Shi, Junjie
• Format: Journal Article
• Language: English
• Published: IEEE 2022
• Subjects: antenna gain; Antenna measurements; antenna sensors; Antennas; Ice; ice sensing; impedance matching; materials; Radio frequency; Radiofrequency identification; relative permittivity measurement; Resonators; RF ice sensing; RFID; Sensors; wireless sensing
• ISSN: 2637-6431; 2637-6431
• DOI: 10.1109/OJAP.2022.3182770

Remote ice detection has emerged as an application of Radio Frequency (RF) sensors. While antenna-based "RFID" sensing can detect various measurands, antenna-based sensors are not currently designed based on a systematic methodology, and in most cases may have a low sensitivity requiring specialist hardware or broadband interrogation signals, incompatible with spectrum regulations. Here, we develop a systematic methodology for designing an antenna-based sensor, applicable to measurands inducing a dielectric change in the near-field of the antenna. The proposed methodology is applied to designing printable antennas as highly-sensitive sensors for detecting and measuring the thickness of ice, demonstrating best-in-class sensory response compared to more complex antenna designs. Antenna design is investigated systematically for wireless interrogation in the 2.4 GHz band, where it is found that a loop antenna outperforms a dipole owing to its more distributed capacitance. The antenna's realized gain was identified as the optimum parameter-under-test, with "positive" sensing proposed as a method of improving linearity and immunity to interference. The developed loop antenna sensor exhibits resilience to interference and applicability to different real-world deployment environments, demonstrated through over 80% average ice thickness measurement accuracy and at least 5 dB real-time sensitivity to ice deposition.