A High-Q Microwave Antenna Sensor Based on Multiple Ring Resonators for Ice Monitoring

In this paper, we design a microwave antenna sensor with a high quality factor ($Q$) based on multiple ring resonators for passive and efficient ice detection applications. The sensor uses a microstrip antenna structure with concentric ring resonators to achieve multi-resonance mechanisms in a compact planar design. The proposed sensor array operates in the frequency range of 1.0 GHz to 5.0 GHz with a$Q$value as high as 827. The sensor works by detecting significant differences in the dielectric constants of air, ice, and water. Among them, the outer ring resonator is mainly used as sensitive unit for ice detection, which can produce a resonant frequency shift up to 1.16 GHz during the phase change process between ice and water. The inner ring resonator achieves 3-bit encoding capability through multi-frequency resonance. To enhance the coding stability, the inner ring of the resonator is covered with a polydimethylsiloxane (PDMS) protective coating, which effectively avoids interference from the external dielectric environment. The simulated results show that the proposed sensor has multi-resonance characteristics and excellent coding expansion capabilities. At the same time, the shielding ground plate set on the back effectively isolates the interference of the installation background material, so that the sensor can reliably monitor ice accumulation under various environmental conditions.