Accession Number : AD0639500

Title :   AN EXPERIMENTAL STUDY OF GROUND WAVE PROPAGATION ACROSS SEMI-INFINITE STRIPS AND ISLANDS.

Corporate Author : COLORADO UNIV BOULDER DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : Tsukamoto,W. I. ; King,R. J. ; Maley,S. W.

Report Date : 17 MAR 1966

Pagination or Media Count : 70

Abstract : Experimental amplitude and phase measurements of electromagnetic ground wave propagation across semi-infinite strips and islands were conducted for normal incidences. Models for propagation were used with aluminum plates simulating highly conducting media and water simulating imperfectly conducting media. The frequency used was 4.2937 Gc/s. An open-end waveguide located at the water surface and a small switching dipole were used as the transmitting and receiving antennas, respectively. Both amplitude and phase measurements were made by using a modulated scattering dipole technique. The theoretical formulation for normal incidence very low frequency (VLF) ground wave propagation across a simple mixed path was developed by J. R. Wait, using a perturbation technique. Wait's work was extended to semi-infinite strips and islands by R. J. King who used an equiavalent formulation in an elliptic coordinate system. In both formulations, an approximate solution for the forund wave attenuation function was obtained. Computer methods were used by King for numerical calculations. The experimental data obtained verified the theoretical calculations and also substantiated the limitations of theory implied in the formulation. (Author)

Descriptors :   (*RADIO WAVES, PROPAGATION), LOW FREQUENCY, VERY LOW FREQUENCY, ELECTROMAGNETIC RADIATION, TERRAIN, LAKES, ISLANDS, PHASE MEASUREMENT, EXPERIMENTAL DATA, WAVE FUNCTIONS

Subject Categories : Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE