Classifications

• • E—FIXED CONSTRUCTIONS
  • E21—EARTH DRILLING; MINING
  • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
  • E21B47/00—Survey of boreholes or wells
  • E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
  • E21B47/14—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves
  • E21B47/18—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves through the well fluid, e.g. mud pressure pulse telemetry
  • E21B47/20—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves through the well fluid, e.g. mud pressure pulse telemetry by modulation of mud waves, e.g. by continuous modulation
• • E—FIXED CONSTRUCTIONS
  • E21—EARTH DRILLING; MINING
  • E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
  • E21B47/00—Survey of boreholes or wells
  • E21B47/12—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling
  • E21B47/14—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves
  • E21B47/18—Means for transmitting measuring-signals or control signals from the well to the surface, or from the surface to the well, e.g. for logging while drilling using acoustic waves through the well fluid, e.g. mud pressure pulse telemetry
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
  • H03L7/00—Automatic control of frequency or phase; Synchronisation
  • H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
  • H03L7/08—Details of the phase-locked loop
  • H03L7/10—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range
  • H03L7/101—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range using an additional control signal to the controlled loop oscillator derived from a signal generated in the loop
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03L—AUTOMATIC CONTROL, STARTING, SYNCHRONISATION, OR STABILISATION OF GENERATORS OF ELECTRONIC OSCILLATIONS OR PULSES
  • H03L7/00—Automatic control of frequency or phase; Synchronisation
  • H03L7/06—Automatic control of frequency or phase; Synchronisation using a reference signal applied to a frequency- or phase-locked loop
  • H03L7/08—Details of the phase-locked loop
  • H03L7/10—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range
  • H03L7/107—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range using a variable transfer function for the loop, e.g. low pass filter having a variable bandwidth
  • H03L7/1075—Details of the phase-locked loop for assuring initial synchronisation or for broadening the capture range using a variable transfer function for the loop, e.g. low pass filter having a variable bandwidth by changing characteristics of the loop filter, e.g. changing the gain, changing the bandwidth
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L27/00—Modulated-carrier systems
  • H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
  • H04L27/22—Demodulator circuits; Receiver circuits
• • H—ELECTRICITY
  • H04—ELECTRIC COMMUNICATION TECHNIQUE
  • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
  • H04L27/00—Modulated-carrier systems
  • H04L27/18—Phase-modulated carrier systems, i.e. using phase-shift keying
  • H04L27/22—Demodulator circuits; Receiver circuits
  • H04L27/227—Demodulator circuits; Receiver circuits using coherent demodulation
  • H04L27/2275—Demodulator circuits; Receiver circuits using coherent demodulation wherein the carrier recovery circuit uses the received modulated signals

Applications Claiming Priority (3)

Publications (1)

Family

ID=27420508

Family Applications (1)

Country Status (13)

Families Citing this family (15)

Family Cites Families (3)

• 1979
  • 1979-02-14 NO NO790496A patent/NO790496L/en unknown
  • 1979-02-22 PH PH22226A patent/PH18212A/en unknown
  • 1979-02-22 IT IT20429/79A patent/IT1111989B/en active
  • 1979-02-22 GR GR58435A patent/GR66583B/el unknown
  • 1979-02-23 DE DE19792907085 patent/DE2907085A1/en not_active Withdrawn
  • 1979-02-23 BR BR7901224A patent/BR7901224A/en unknown
  • 1979-02-27 GB GB8115020A patent/GB2087177B/en not_active Expired
  • 1979-02-27 OA OA56744A patent/OA06193A/en unknown
  • 1979-02-27 IN IN179/CAL/79A patent/IN153402B/en unknown
  • 1979-02-27 FR FR7905021A patent/FR2434522A1/en not_active Withdrawn
  • 1979-02-27 NL NL7901534A patent/NL191549C/en not_active IP Right Cessation
  • 1979-02-27 AU AU44621/79A patent/AU524811B2/en not_active Ceased
  • 1979-02-27 GB GB7906841A patent/GB2015307A/en not_active Withdrawn
  • 1979-02-27 GB GB8115019A patent/GB2094578B/en not_active Expired
  • 1979-08-08 IE IE561/79A patent/IE48319B1/en not_active IP Right Cessation
  • 1979-09-24 FR FR7924006A patent/FR2433860A1/en active Granted
• 1982
  • 1982-07-06 AU AU85672/82A patent/AU8567282A/en not_active Abandoned
  • 1982-07-06 AU AU85673/82A patent/AU8567382A/en not_active Abandoned

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