Predicting radiation characteristics from antenna physical dimensions

This report explains the fundamental theory and equations used in writing a set of software applications which predict antenna radiation parameters. Each application predicts the radiation characteristics of a particular type of antenna over a planar surface which serves as a model of either earth or seawater. The radiation parameter predictions are based solely on an antenna's physical dimensions, the properties of the underlying surface, and electromagnetic theory. Existing electric field equations provide the basis for radiation parameter predictions, and the accuracy of the predicted radiation parameters is totally dependent upon the extent to which the electric field equations used realistically model the actual radiated electromagnetic fields of the antennas. In addition to a review of applicable electromagnetic field theory, this report is also intended to be a user's guide for the corresponding computer applications. The appendices contain computer hardcopies of sample calculations for several antenna types and remarks regarding the conformity of predicted radiation parameters to expectations. Radiation parameters computed thus far are consistent with expectations based on other computational programs and empirical measurements.