# The Fresnel Zone Calculator

A choice of two calculations: one based upon distance and the other based upon co-ordinate selection.

## Define a Distance

The simplest calculation using an ideal earth globe. The distance between the link ends is defined. The erth curvature
is calculated and refraction added

Distance

## Define the Co ordinates

The link end co-ordinates are given: this allows the terrain profile to be calculated. The earth curvature is compensated for before
calculating the fresnel zone.

Co-ordinates