Accession Number : AD0721371
Title : On Calculations of the Modal Parameters of an Idealized Earth-Crust Waveguide.
Descriptive Note : Technical rept.,
Corporate Author : OFFICE OF TELECOMMUNICATIONS BOULDER COLO INST FOR TELECOMMUNICATION SCIENCES
Personal Author(s) : Spies,Kenneth P. ; Wait,James R.
Report Date : 17 MAR 1971
Pagination or Media Count : 64
Abstract : Calculations for the mode characteristics for the earth-crust waveguide are presented. The formulation allows for any depth-conductivity profile, but the specific results are only for a homogeneous sub-surface waveguide region with a finitely conducting lower layer and a perfectly conducting upper layer. Attenuation rates of the order of 1 dB/km are possible for operating frequencies of 20 kHz or lower if the crystalline rock in the waveguide has conductivities less than 0.000001 mhos per meter. The tabular data include results for the phase velocity and excitation factors of the dominant modes. (Author)
Descriptors : (*RADIO TRANSMISSION, UNDERGROUND), WAVEGUIDES, STRATIGRAPHY, MATHEMATICAL ANALYSIS, VERY LOW FREQUENCY
Subject Categories : Radiofrequency Wave Propagation
Distribution Statement : APPROVED FOR PUBLIC RELEASE