Self-Complementary Archimedean Spiral UHF Antenna for Partial Discharge Detection with Parallelogram Geometry Feed

This work presents the circularly polarized antenna design operating in the ultra-high frequency (UHF) band, which is developed to detect partial discharge (PD) signals functioning across a broad spectrum from 0.8 GHz up to 3 GHz.The projected design includes a self-complementary Archimedean spiral antenna with two spiral slots and a parallelogram-shaped central feed port. This eliminates the need for a cavity, absorber, and balun. The antenna was built using an FR-4 substrate with a dielectric constant of 2.4 and a metal layer thickness of 0.035mm. This study depicts that the proposed antenna achieved less than -10 dB reflection coefficient over the entire UHF frequency range and - 46.21 dB at 1.05 GHz. The results also show a good VSWR, better gain, and excellent impedance matching (50 Ω).