US 4,786,914 AGranted

Meanderline polarization twister

AssigneeE-Systems, Inc.

InventorsTe-Kao Wu, Darrell L. Helms

Life of this patent

Estimating the term…

Loading patent…

Abstract

A polarization twister for twisting the polarization of a wide angle incident electromagnetic wave is described. Specifically, the polarization twister includes a reflector for reflecting the wide angle incident electromagnetic wave, a dielectric substrate having a longitudinal axis, a spacer bonded on a first side thereof to the dielectric substrate and on a second side thereof to the reflector, and an array of meanderline conductive strips etched on the dielectric substrate. Each meanderline conductive strip has an axis extending at a 45.degree. angle with respect to the longitudinal axis of the dielectric substrate. In operation, the meanderline conductive strips serve to advance the phase of a parallel component of an incident E-field vector, and delay the phase of the perpendicular component thereof. Accordingly, the reflected field has its polarization twisted 90.degree. from the incident polarization.

Claims13

Dependent claims

A wide angle polarization twister fo twisting the polarization of an incident electromagnetic wave of wavelength .lambda., comprising:

a dielectric substrate having a longitudinal axis and a dimension in thickness equal to 0.017.lambda.;
a spacer having first and second sides and a dimension "x" given by the expression x=0.275 .lambda., said dielectric substrate bonded to the first side of the spacer;
a single layer of a plurality of meanderline conductive strips etched on said dielectric substrate, each meanderline conductive strip having a width "d"=0.31 .lambda. and an axis extending at a 45.degree. angle with respect to the longitudial axis of said dielectric substrate;
a reflector bonded to the second side of the spacer for reflecting the wide angle incident electromagnetic wave with its polarization twisted 90.degree.;
and
wherein each of the meanderline conductive strips has a longitudinal period "a", a distance "b", a transverse length "h", and a width "w" determined by the wavelength .lambda. to provide the 90.degree. twist of the electromagnetic wave by the single layer of meanderline conductive strips.

3 more elements

Dependencies are inferred from the claim text.