Mining Publication: Theoretical Noise and Propagation Models for Through-the-earth Communication
Original creation date: September 1982
A survey of the literature on ELF and VLF atmospheric noise has been made. Most measurements have concentrated on the vertical electric field and the horizontal magnetic field rather than the vertical magnetic field which is of interest in transmission between horizontal loops. The limited vertical magnetic field data indicates that the vertical component is generally 10 to 20 dB below the horizontal component. Three laterally inhomogeneous earth models have been analyzed for conversion of horizontal to vertical magnetic field. The rough surface model examines surface effects, the inhomogeneous thin sheet model treat volume effects, and the buried cylinder model treats localized man-made effects. All three models predict the possibility of significant conversion from horizontal to vertical magnetic field. A thin sheet model has also been used to examine transmission from a buried magnetic dipole source. It found that the predicted fields more nearly model the measured data than does the homogeneous half-space model.
Authors: DA Hill, JR Wait
Contract/MOA Report - September 1982
NIOSHTIC2 Number: 10003392
National Telecommunications & Information Admin., Institute for Telecommunication Sciences U.S. Bureau of Mines contract No. J0113058. NTIS: PB84-166628, 1982; Sept :52 pages
See Also
- Advanced Tutorial on Wireless Communication and Electronic Tracking: Communication System Performance
- Communication Systems Research At Bruceton Safety Research Mine
- Experience with an Integrated, Computer-Controlled Communications and Monitoring System at the Robena Mine
- Propagation of EM Signals in Underground Mines
- Research and Development Contract for Coal Mine Communication System: Volume 3 - Theoretical Data Base
- Technology News 551 - Through-the-Earth, Post-Accident Communications—an Emerging Technology - TN-No. 551
- Through-The-Earth Wireless Real-Time Two-Way Voice Communications
- Ultra-Low Frequency Through-the-Earth Communication Technology
- Vertical Magnetic Noise in the Voice Frequency Band Within and Above Coal Mines
- Wireless Through-The-Earth Modeling and Support
- Page last reviewed: 9/21/2012
- Page last updated: 9/21/2012
- Content source: National Institute for Occupational Safety and Health, Mining Program