Patent · US Expired

Efficient processing of NMR echo trains

US5517115A · kind A · utility

87Cited by
7References
29Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 16, 1993
Grant dateMay 14, 1996
Priority date
Expiry dateDec 16, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R33/4625
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus is disclosed for efficient processing of nuclear magnetic resonance (NMR) echo trains in well logging. Apriori information about the nature of the expected signals is used to obtain an approximation of the signal using a set of pre-selected basis functions. A singular value decomposition (SVD) is applied to a matrix incorporating information about the basis functions, and is stored off-line in a memory. During the actual measurement, the apparatus estimates a parameter related to the SNR of the received NMR echo trains and uses it to determine a signal approximation model in conjunction with the SVD of the basis function matrix. This approximation is used to determine in real time attributes of the earth formation being investigated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.