Origin of this Application
When analyzing radar data, it is often helpful to know the height of the radar volume. Numerous charts exist that show this information on a gross scale. We thought a simple interactive SWF to compute this information for a specific range gate would be more applicable. The application provides the user the beam center height, beam top height, beam bottom height, and the beam width. Most charts that provide beam heights don't contain information on these other parameters.
The application derives this information using some simple approximations and equations. Assuming a standard atmosphere, the height of a radar beam can be computed using the following equation:
h = (R*sin(PHI)) + (R2 /2*IR*Re),
h = height of the beam centerline above radar-level (ARL) in km,
The beamwidth of the radar beam is calculated using
To determine the beam top and beam bottom heights, the component of the beamwidth perpendicular to the ground is first calculated using
This distance is then divided in half and added (subtracted) from the beam center height to get the beam top (beam bottom) height.