volume | PIER Journals

Abstract

This paper presents the design and implementation of a microstrip patch sensor based on a single complementary split ring resonator (SC−SRR), operating at a resonant frequency of 2.44 GHz for salinity detection. The sensor evaluates liquid under test (LUT) by monitoring variations in resonant frequency, reflection coefficient, and quality factor to extract the complex permittivity. The proposed design was simulated using High Frequency Structure Simulator (HFSS) and fabricated on an FR−4 substrate, incorporating a Teflon container to prevent direct contact with the sensing surface. Simulated and measured results exhibit a significant agreement, validating the sensor's performance. A frequency shift of 104.4 MHz was observed as the salinity concentration varied from 0 to 100 parts per thousand, attributed to dielectric perturbation effects. The proposed sensor demonstrates several advantages, including non-contact and non-destructive measurement, reusability, cost-effectiveness, high sensitivity, minimal fluid volume requirement, and reliable accuracy. These features highlight its potential for applications requiring precise and efficient.

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Mr. Hussein Jasim

Dr. Amer Abbood Al-Behadili

Dr. Sadiq Ahmed