Zeroth-Order Resonator Based on Mushroom-like Structure for Liquid Mixture Concentration Sensing of Sodium Chloride Solution

This paper presents the liquid-mixture sensor using a zeroth-order resonator (ZOR) based on mushroom-like structure. The mushroom-like structure is designed using Jerusalem shape for reducing the size of a resonator and providing a high Q-factor that operating frequency at 5.90 GHz. By using the perturbation theory, each dielectric properties of the liquid-mixture affect to the resonance frequency. In this paper, four conditions, only zeroth-order resonator sensor, with empty Teflon tube, inserting deionized water and inserting Sodium Chloride solution (NaCl), are investigated the sensor performance with the reflection coefficient,| S11|, technique. The measured can classify the liquid under test (LUT) by detecting the resonant frequency change of the reflection coefficient,| S11|. The zeroth-order resonator sensor also offers other advantages, e.g., non-destructive method, real-time monitoring and no life-cycle limitation.