System for doppler positioning of seismic sensors and method
AssigneeSeabed Geosolutions B.V.
InventorsOlivier Winter, Thomas Bianchi
Life of this patent
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Abstract
Method and system for determining positions of underwater sensors. The method includes sending a Doppler variant signal from a moving source; recording the signal with the at least one seismic sensor; evaluating a frequency drift of the recorded signal; and determining a position of the at least one seismic sensor based on the evaluated frequency drift and a source movement relative to the at least one sensor.
Claims19
A method for determining a position of at least one seismic sensor when deployed underwater, the method comprising:
- sending a first mono-frequency signal from a moving source;
- recording the first signal with the at least one seismic sensor;
- evaluating a frequency drift of the recorded first signal;
- determining a position of the at least one seismic sensor based on the evaluated frequency drift and a source movement relative to the at least one seismic sensor;
- repetitively sending the first signal from the source;
- recording locations of the source and associated times when repetitively emitting the first signal;
- determining a modeled frequency drift curve based on the first signal and its corresponding times, radial velocities of the source, and medium parameters;
- and
- determining a measured frequency drift curve from the recorded pressures, particle velocities or particle accelerations and their corresponding times.
A method for determining a position of at least one seismic sensor when deployed underwater, the method comprising:
- emitting a Doppler variant signal from a moving source;
- recording pressures, particle velocities or particle accelerations and associated times with the at least one seismic sensor fixedly attached to the bottom of the ocean, wherein the pressures, particle velocities or particle accelerations contain the emitted Doppler variant signal modulated by the Doppler effect;
- measuring a frequency drift from the recorded pressures, particle velocities or particle accelerations;
- and
- determining a position of the at least one seismic sensor based on the measured frequency drift and a source movement relative to the at least one seismic sensor,
- wherein the Doppler variant signal is one of a sine wave, a triangular wave, a rectangular wave or a combination thereof.
A system for determining a position of at least one seismic sensor when deployed underwater, the system comprising:
- a moving source configured to send a Doppler variant signal having a first frequency;
- the at least one sensor configured to record pressures, particle velocities or particle accelerations and associated times, wherein the pressures, particle velocities or particle accelerations contain the Doppler variant signal modulated by Doppler effect;
- and
- a control device configured to,
- receive data from the source and from the at least one sensor to calculate a frequency drift from the recorded pressures, particle velocities or particle accelerations, and
- determine a position of the at least one seismic sensor based on the calculated frequency drift and a source movement relative to the at least one sensor,
- wherein the Doppler variant signal is one of a sine wave, a triangular wave, a rectangular wave or a combination thereof.
Dependencies are inferred from the claim text.