WKB Mode Summing Program for Dipole Antennas of Arbitrary Orientation and Elevation for VLF/LF Propagation. Calculation of VLF/LF Field Strengths in the Earth-Ionosphere Waveguide

摘要

A computer program was developed for calculating vlf/lf field strengths in the earth-ionosphere waveguide whose characteristics may vary along the direction of propagation. The computer program described in this report is a modified version of that described in NELC Interim Report 713, WKB Mode Summing Program for VLF/LF Antennas of Arbitrary Length, Shape, and Elevation. Changes consist of an increase in the number of waveguide slabs from 25 to essentially an unlimited number, more convenient formatting of the input data, especially in the reduction from three to two cards per waveguide mode, an increase in the number of allowable modes from 15 to 30, and the addition of two new output options. This program is referred to as WKBFLDS or FLD4. Use of this program is recommended in instances where the characteristics of the earth or ionosphere vary slowly along the propagation path.