Characterizing Carbon Fiber Conductivity for Structural Antenna Applications

This study explores the potential applications of carbon fiber composite material for structural antennas. Carbon fiber composite materials provide excellent specific strength and stiffness; however, their electrical properties, such as conductivity, are not well established, especially in the very high-frequency (VHF) range. Knowledge of a material's conductivity is required for electrical performance estimation through simulations. Through combined experimental and simulated analysis of multiple carbon fiber antennas, the effective conductivity for a biaxial weave carbon fiber composite was determined to be between 7000 and 13 000 S/m in the VHF spectrum. Carbon fiber antenna performance is found to be particularly sensitive to the contact between the carbon fibers and the copper feed; however, radiation efficiencies (REs) of carbon fiber composite antennas are found to be within 2%-10% of a geometrically identical copper antenna, and their bandwidths are nearly identical. The electrical performance of carbon fiber composite antennas demonstrates significant promise for structural antenna applications in the VHF range.