Radiant Energy Display and Analysis Software Package (REDAP) is a computer program for processing antenna-radiation- pattern data that have been preprocessed by a data-collection program and stored in a spherical-coordinate format. REDAP is designed specifically for application to data generated in testing of antennas in an anechoic chamber at Johnson Space Center; parts of REDAP may be reusable for processing antennatest data collected elsewhere. REDAP provides a graphical user interface (GUI) and executes mathematical and plotting routines on a personal computer. The routines include statistical calculations (e.g., maximum, minimum, 3-dB-falloff points, and percent coverage); addition and subtraction of offsets; multiplication and division by scaling factors; and computation of circular-polarization characteristics from linear-polarization measurement data.

A Sample Polar Plot illustrates one of the formats that can be generated from REDAP.
REDAP can display radiation-pattern data in a variety of formats that include, for example, lines plotted on rectangular coordinates, images of radiation patterns in three-dimensional space, and contour plots on polar coordinates (see figure). All characteristics of a display, including contents of plots, coordinate axes, marks, colors, and the destination (e.g., printer or file) to which the display data are to be sent are controlled through a series of GUI dialog boxes.

This work was done by Jim Siekierski of Johnson Space Center and Ash Henson of Lockheed Martin Corp.

NASA Tech Briefs Magazine

This article first appeared in the September, 2007 issue of NASA Tech Briefs Magazine.

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