Loading patent…
AssigneeHalliburton Energy Services, Inc.
InventorsWallace R. Gardner, Vimal V. Shah, Donald Kyle
Estimating the term…
A reliable downhole acoustic telemetry system with increased data rate is disclosed. In one embodiment, the telemetry system includes a receiver having an envelope-detection demodulator and a multipulse-block distance detector that compares a baseband envelope signal to stored waveforms and indicates for each symbol interval the multipulse block having the waveform closest to the baseband envelope signal. The receiver may also include a timing recovery module that models the baseband envelope signal for the detected multipulse blocks and determines a distance for early-sampling and late-sampling of the baseband envelope signal. The timing recovery module then provides a sampling clock that minimizes the average difference between the early- and late-sampling distances. The telemetry system may further include a transmitter having an encoder and a modulator. The encoder converts a data signal into a sequence of multipulse blocks having a settling interval between the blocks. The modulator modulates the multipulse block sequence with a carrier frequency to produce an amplitude modulated signal. The telemetry system may have the transmitter and receiver coupled to a tubing string by an acoustic signal generator and an acoustic transducer, respectively. The acoustic signal generator converts the amplitude modulated signal into acoustic waves that propagate along the tubing string to the acoustic transducer, which then converts the acoustic waves into a receive signal. The system and method disclosed may advantageously provide a robust, low-power telemetry system that communicates telemetry along a tubing string at a rate that is at least an order of magnitude greater than existing acoustic telemetry methods.
A telemetry receiver that comprises:
A telemetry transmitter that comprises:
A telemetry system that comprises:
A method for communicating telemetry data via a tubing string, wherein the method comprises:
Dependencies are inferred from the claim text.