Downhole telemetry signal modulation using pressure pulses of multiple pulse heights
US9574441B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 2013 |
| Grant date | Feb 21, 2017 |
| Priority date | — |
| Expiry date | Jan 31, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/34
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A method for modulating a downhole telemetry signal uses a fluid pressure pulse generator that generates pressure pulses of multiple pulse heights in a drilling fluid. The method comprises: converting measurement data into a bitstream comprising symbols of a selected symbol set; encoding the bitstream into a pressure pulse telemetry signal using a modulation technique that includes amplitude shift keying, wherein each symbol of the selected symbol set is assigned a pressure pulse having a unique amplitude; and generating pressure pulses in the drilling fluid corresponding to the telemetry signal. Alternatively, the method can comprise a modulation technique that includes amplitude shift keying and phase shift keying and wherein each symbol of the selected symbol set is assigned a pressure pulse having a unique combination of amplitude and phase.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.