# Coplanar Conical Plates in a Uniform Dielectric Lens with Matching Conical Plates for Feeding a Paraboloidal Reflector

## Abstract

One form of an impulse radiating antenna (IRA) consists of a paraboloidal reflector fed by conical transmission lines that propagate a spherical TEM wave, which originates from the focal point of the reflector. A diagram which depicts such an IRA is shown schematically in Figure 1. The design considerations of a uniform dielectric lens useful in launching a spherical TEM wave onto such a paraboloidal reflector have been investigated in earlier work^{1, 2, 3}, and the geometrical parameters for the lens design are indicated in Figure 2. The lens design in essence consists of specifying certain parameters. These include the cylindrical radius, *h*, of the outermost ray which intercepts the reflector, the relative permittivity *ε* _{ r } of the lens medium, and the angle, *θ* _{ r } ^{(out)}, from the apex of the conical transmission line (focal point) to the edge of the reflector. This angle is determined by the reflector geometry through the ratio *F*/*D*, where *F* is the focal distance from the center of the reflector and *D* is the reflector diameter. We also need to specify the angle *θ* _{ r } ^{(in)} made by the line inside the lens with respect to the directions of launch.

## Keywords

Characteristic Impedance Spherical Wave Reflector Geometry Lens Design Lens Region## Preview

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## References

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