Enhanced performance antennas for NMR logging
US6586932B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 2002 |
| Grant date | Jul 1, 2003 |
| Priority date | — |
| Expiry date | Oct 16, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/32
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An antenna design for a downhole nuclear magnetic resonance logging tool is enhanced to shape the resultant RF field generated by the antenna. The enhancement is accomplished by adding additional turns to a portion of the antenna, either circumscribing a ferrite material or located on the surface of an at least partially non-conductive material. The additional turns or half turns in combination with the RF field from parallel antenna portions result in a RF field contribution that is proportionally higher than the RF field contribution from the coil portions which are not enhanced. Further, the total RF field can be shaped over a earth sample region depending on placement of the enhancing turns. In this way, for example, the total RF field can be generated to achieve an orthogonal alignment with a static magnetic field over a larger region of the sample.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.