Radome wall design having broadband and mm-wave characteristics

DETAILED DESCRIPTION These and other objects of the invention are accomplished by a multi-layer radome construction which may be termed a "D-sandwich" and allows excellent transmission efficiency over the entire spectrum of DC to at least 100 GHz.
The radome wall construction comprises a core layer of a low dielectric constant material bounded by intermediate layers of high dielectric constant material which themselves are bounded by additional layers of low dielectric constant material.
The terms "low" and "high" are used herein in a relative sense with specific values of the dielectric constants being within the skill of a radome designer to determine, based upon the specific intended use and conditions of use of the radome being designed.
Each of the layers, including the low dielectric constant layers, will have a substantial electrical effect upon the performance of the radome, i.
e.
removal of any layer will substantially change the electrical performance of the radome.
In a preferred form, the multi-layer radome wall may utilize material having a low dielectric constant such as DuPont's Teflon.
RTM.
polytetrafluoroethylene polymers or Allied-Signal, Inc.
's Spectra.
RTM.
highly oriented polyethylene polymers in a resin matrix, and the high dielectric constant material layers may be formed from a resin matrix such as polyester or epoxy having glass fibers incorporated therein for reinforcement of these layers.
The radome may be further provided with one or more conventional surface protective coatings which are very thin layers of materials which provide enhanced erosion protection for such as rain or other precipitation as well as ultraviolet light protection.
The coatings provide desired resistance for use under certain environmental conditions without destroying the desired transmission characteristics of the radome and without exhibiting any substantial electrical effect on the performance of the radome.
The dielectric constants, loss tangents, and thicknesses of the various materials to be used in the multi-layer constructions of the invention are designed to provide excellent transmission efficiency over the frequency range desired