Method and apparatus for communicating signals from within an encased borehole
US5576703A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1995 |
| Grant date | Nov 19, 1996 |
| Priority date | — |
| Expiry date | Dec 19, 2015 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/13
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method and apparatus for communicating signals from within an encased borehole including a wireless communications system for transmitting down-hole environmental data signals between a down-hole tool and a surface receiver. The down-hole tool is disposed within a borehole encased in an electrically conductive casing; the receiver is located at the ground surface. The tool includes a conductive upper and lower tool housing, a plurality of down-hole sensors, and a signal generating device. The sensors and signal generating device are housed within the tool. The generating device receives analog or digital signals of the down-hole environmental conditions from the sensors, converts these signals into a modulation pattern signal which is applied to a carrier signal and conducts a modulated carrier signal into the upper and lower tool housings. An upper contactor or spreader electrically connects the upper housing to a first position on an inside wall of the casing. Similarly, a lower contactor or spreader electrically connects the lower housing to a second position on the inside wall of the casing. The first and second positions are spaced-apart by a pre-determined separation, and d…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.