Towards the Optimal Antenna-Based Wireless Sensing Strategy: An Ice
Sensing Case Study
Abstract
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.