Wireless subterranean signaling method
US3967201A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 25, 1974 |
| Grant date | Jun 29, 1976 |
| Priority date | — |
| Expiry date | Jan 25, 1994 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/13
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A relatively low frequency wireless electromagnetic communication link is established through a subterranean lossy medium such as ground or water by launching and propagating magnetic waves of generally vertical magnetic polarization through the intervening subterranean region of earth or water between a pair of magnetic dipole antennas. A suitable subterranean dipole magnetic antenna includes an elongated electrical solenoid having a ferromagnetic core, as of ferrite or laminated iron. Relatively low frequency magnetic waves are utilized wherein the frequency is related to the conductivity of the subterranean region and distance between transmitter and receiver such that the range is less than 10 skin depths at the carrier frequency.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.