Adaptive telemetry system for hostile environment well logging
US5365229A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 22, 1994 |
| Grant date | Nov 15, 1994 |
| Priority date | — |
| Expiry date | Mar 22, 2014 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/12
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The operation of hostile environment logging tools at temperatures up to 250.degree. C. stresses not only the tools, it also places severe demands upon the wireline telemetry due to the wide variations in the logging cable transmission characteristics. A robust adaptive wireline telemetry system for use in hostile environments has been developed that combines sophisticated digital communication methods with modern Digital-Signal-Processing (DSP) techniques. The downhole telemetry transmitter outputs a multilevel signal. The uphole receiver includes an adaptive transversal-filter equalizer (TFE) that is continually optimized to correct for changing signal distortion. The system operates robustly at high data rates over the temperature range of 0.degree. to 250.degree. C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.