Patent · US Expired

Downhole telemetry system using discrete multi-tone modulation having repeated symbols

US7026952B2 · kind B2 · utility

10Cited by
11References
38Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 21, 2003
Grant dateApr 11, 2006
Priority date
Expiry dateAug 14, 2024

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V11/002
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A downhole telemetry system and method using discrete multi-tone modulation having repeated symbols. The system includes a surface receiver, a cable, and a downhole transmitter coupled to the surface receiver via the cable. The transmitter communicates a time-domain signal to the receiver. The time-domain signal has a cyclic prefix for a symbol at least as long as the length of the symbol. The system may alternatively include the time-domain signal having a symbol followed immediately by a copy of the symbol. The method includes receiving a time-domain signal carrying desired information at specific frequencies. The signal has at least one symbol. The method includes prepending a cyclic prefix having first length to the beginning of the symbol. The cyclic prefix has a second length no longer than the first length. The method may alternatively include appending a copy of the at least one symbol to the end of the at least one symbol.

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