Radio navigation coordinate corrections for excess phase accumulation over irregular, inhomogeneous terrain

J. Ralph Johler and Duane C. Hyovalti

Abstract: This report reviews the techniques for calculating position with the Loran navigation system, including the use of phase correction factors computed for ground wave propagation over a smooth spherical earth. If the earth is rough or inhomogeneous, there may be an excess phase accumulation over that for a smooth earth. Some time-difference calculations for 100 kHz propagation over a perfectly-conducting surface with a uniform distribution of finitely-conducting, hemispherical, bosses show large but physically possible excess phase accumulations. A computer program to calculate time differences, gradients, latitude, longitude, and distances along a geodetic line is listed. Sample input and output are included.

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