In this study, polymer matrix composites based on high-density polyethylene (HDPE) and recycled HDPE (HDPEr) were reinforced with zinc oxide nanoparticles (ZnO NPs). Four formulations (M1-M4) with HDPE/HDPEr/ZnO NP mass ratios of 50/50/0, 48/47/5, 45/45/10, and 43/42/15 were produced via melt injection molding. Disc-shaped samples (Ø30 ± 0.1 mm × 2 ± 0.1 mm) were evaluated in unaged and aged states (840 h at 100% humidity and 100 °C) using scanning electron microscopy, X-ray diffraction, ultraviolet–visible and Fourier-transform infrared spectroscopy, water absorption, thermal resistance, and mechanical and dielectric testing. Among all composites, M2 showed the best performance, with the highest aging resistance (estimated lifetime of 3891 h in humidity and 2361 h in heat). It also exhibited superior mechanical properties, with the highest indentation hardness, Vickers hardness, and elastic modulus before (0.042 GPa, 3.846 HV, and 0.732 GPa) and after aging under humidity (0.042 GPa, 3.932 HV, 0.706 GPa) and elevated temperature (0.085 GPa, 7.818 HV, 1.871 GPa). Although ZnO NPs slightly reduced electrical resistivity, M2 showed the most stable dielectric properties. In its unaged state, M2 had 22%, 30%, and 3% lower surface resistivity, volume resistivity, and dielectric strength, respectively, than M1 polymer. M2 was identified as the optimal formulation, combining mechanical strength, dielectric stability, and resistance to moisture and heat.

This study emphasizes how the Global Navigation Satellite System (GNSS) receiving antenna technology transcends the boundaries of traditional ceramics manufacturing techniques, expanding their design options and improving the functional attributes of ceramic components for GPS, Galileo, GLONASS, and BeiDou applications. Ceramics exhibit exceptional material characteristics, such as excellent thermal resistance, outstanding electrical insulation, considerable hardness, and notable wear resistance, making them suitable for GNSS technology, due to their capacity to form intricate shapes and microstructures for applications in aerospace, electronics, and automotive sectors. The research systematically outlines the impact of advanced ceramic-based structures upon various antenna design, technology and types, relevant to their particular applications: antennas with alumina substrates, antennas that use FR4 substrate, antennas that use a PCB substrate, antennas with a dielectric ceramic backing, and antennas employing different concepts of Rogers substrates. This study also highlights temperature-stable ceramics, which represent a novel development in research, crucial for improving GNSS technology due to their ability to retain a consistent dielectric constant over a broad temperature range; these ceramics eliminate frequency variations in patch and dielectric resonator antennas, guaranteeing precise signal reception, even in extreme outdoor and satellite conditions.