Accession Number : ADP006296

Title :   Upgrades for Efficient 3D Ionospheric Ray Tracing. Investigation of HF NVIS Effects,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s) : Reilly, Michael H.

Report Date : 03 MAY 1990

Pagination or Media Count : 10

Abstract : An earlier, three-dimensional (3D) ray-tracing program has been upgraded to include magnetic field effects, variable step sizes, improved propagation loss computation, and efficient homing and focusing computation algorithms. A combination of fourth-order Runge-Kutta and Adams methods, with error control, has been included. The program is applied to an investigation of high-frequency (HF) near-vertical-incidence-skywave (NVIS) effects. Model simulations of oblique ionograms are found to be consistent with experiment. Implications for NVIS geolocation are discussed.

Descriptors :   *IONOSPHERIC PROPAGATION, RAY TRACING, THREE DIMENSIONAL, TRANSMISSION LOSS, MAGNETIC FIELDS, RUNGE KUTTA METHOD, HIGH FREQUENCY.

Subject Categories : Radiofrequency Wave Propagation
      Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE