Compact dual-band asymmetrical five-line microstrip sensor based on CSRR for water–ethanol mixtures characterization

Abstract This work presents an innovative compact dual-band microstrip sensor based on a complementary split-ring resonator (CSRR) for the precise characterization of water–ethanol mixtures. The sensor, optimized via HFSS, offers high sensitivity and an impressive quality factor through dual-band operation at 3.5 GHz and 4 GHz. The validity of the sensor’s performance is supported by both simulated and measured results, which demonstrate its capacity to extract the complex dielectric permittivity of liquids. The proposed sensor utilizes CSRR and offers dual-band resonance, making it a promising alternative to traditional CSRR. This innovative sensor’s dual-band capability, achieved through its unique use of CSRR, renders it particularly suitable for applications in chemical and biomedical fields.