A 10 GHz metamaterial sensor to detect SARS COV-2 and dust particles in free space

ABSTRACT

An X-band, free-space microwave sensor consisting of 30 radial spokes connected in a central hub with a gap region was designed, fabricated and tested. The sensor structure results in an electric dipole at 10 GHz with a split circular disc capacitor at the center. Viruses, dust, and soot particles in the gap region change the sensor’s impedance and its reflection coefficient monitored by a horn antenna and a network analyzer. The sensor sensitivity was 85.02 MHz/microliter for deionized water, 89.5 MHz/microliter for uninfected saliva, and 94.6 MHz/microliter for SARS-COV-2 infected saliva with 103 viruses/μL. Its sensitivity to a dielectric sample (ερ~5.84) was 3.23 MHz/mm3, and for iron particles was 16.25 MHz/mm3. All these samples were smaller than λ/30 at 10 GHz and could not be detected on uniform dielectric or metallic substrates without the spoke structure. A 2x2 array of spoke sensors was also constructed and tested as a feasibility study for designing larger metamaterial (MTM) periodic arrays. IEEE