Thin structure HF directional aerial for guided missile - has two conducting plates separated by dielectric layer of width determined by dielectric constant and cone angle of radiation

摘要

The aerial consists of two flat conductors (1,2) connected by a narrow wall (3) of conducting material perpendicular to the flat conductors. The space between the conductors is parallelepipedic and maybe simply air, but is pref. a dielectric material such as epoxy glass of teflon (RTM) glass which need to be either a mm or several mm thick respectivley. The aerial is supplied at a point (P) on the upper plate, which is consequently called the supply plate, the second plate being the earth plate. The aerial may radiate in a narrow angular field. The length of the spaces is several times the wavelength of the radiation in air, and the width of the space is determined by the following relationship lamda/4 root (epsilon- cos squared theta) where epsilon is the dielectric constant of the material filling the space and theta is the cone angle of transmitted radiation.