Abstract:
Passive LC sensors, composed of an inductor (L) and capacitor (C), are widely used in applications where sensors are implanted or operated in hazardous environments. However, their readout typically relies on commercial devices such as impedance analyzers or vector network analyzers, which are not cost-effective for use outside laboratory settings. Existing custom-made readout solutions also often depend on frequency or time-sweep measurements that require relatively complex hardware. This paper presents a novel LC sensor readout method based on single-frequency impedance measurement, featuring a unique approach for directly estimating the sensor’s capacitance. By eliminating the need for measurements with a large number of data points, the proposed method enables capacitance estimation at frequencies different from the sensor’s resonant frequency. The approach is validated through both simulations and experimental results, and its suitability for implementation on embedded hardware platforms is also demonstrated.
The article is available via the following link: https://doi.org/10.1109/TIM.2025.3637952