Conference Paper

Mesh pillowing in deployable offset paraboloidal umbrella reflector antennas

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Abstract

An analytical formula capable of describing, with high accuracy, the offset paraboloidal umbrella reflector mesh shape is presented. This formula takes full account of the pillowing effect, and also applies to the front-end geometry, which is simply a degenerate case of an offset paraboloid. The basic steps used in deriving this formula parallel the ones used for the front-fed geometry. The validity of the analytical solution presented has been confirmed by comparison against a numerical solution obtained using the finite-difference technique.

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Conference Paper
An analytical solution for the umbrella reflector surface shape, including the pillowing contribution, is presented. The solution is simple and sufficiently accurate for most antenna applications, and apart from being useful as a design tool, it can be easily incorporated into an existing computer code, allowing for more realistic evaluations of the umbrella reflector electrical characteristics. The analytical solution was tested by numerically solving the equations using a successive overrelaxation procedure. The gain degradation and the gore-related sidelobes clearly show the significance of pillowing on the antenna radiation characteristics