High data rate wireline telemetry system
US5387907A · kind A · utility
24Cited by
9References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 25, 1993 |
| Grant date | Feb 7, 1995 |
| Priority date | — |
| Expiry date | Jun 25, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V1/22
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a well logging tool forming a data stream for telemetry to the surface, an encoding system is located downhole cooperative with surface located decoding equipment. The encoder converts serial data into NRZ symbols, then duobinary code of seven levels and then into quadrature modulating signals on a complex carrier. The decoder at the well surface receives the quadrature modulated complex carrier, forms inphase and quadrature components and decodes the two components. The decoder includes circuit means removing the intersignal distortion and also intersymbol smearing. This enables very significant telemetry ratio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.