Structural composite materials near a broadband Log-Periodic-Dipole-Array (LPDA)

This paper presents the effects of structural composite material loading on a broadband LPDA. The proposed antenna operates from 350-750 MHz and has a unique bi-layer design where the two antenna trace layers are disposed of on two separate fiberglass composite skin surfaces. The effects of the presence of a tubular structural member on the antenna performance are studied by considering various dielectric materials to mimic a structural support member, such as a spar. Measured VSWR results of the LPDA in the presence of Kevlar structural support member are presented.