Methods for data compression and optimization for downhole telemetry
A method includes obtaining, by a downhole tool, a first shape of sensor data representing one or more characteristics of a wellbore, comparing, by the downhole tool, the first shape with a set of pre-determined reference shapes stored in a downhole memory to select a pre-determined reference shape that can be imposed on the first shape, calculating one or more delta values between the first shape and the selected pre-determined reference shape, and transmitting, by the downhole tool, the pre-determined reference shape and the delta values to a processor at a surface of the wellbore.
1. A method, comprising:
obtaining, by a downhole tool and from a sensor incorporated within the downhole tool, a first shape of sensor data representing one or more characteristics of a wellbore arranged on a polar plot;
selecting, by the downhole tool, a pre-determined shape from a set of pre-determined reference shapes stored in a downhole memory that matches the first shape;
imposing the pre-determined shape on the first shape arranged on the polar plot;
adjusting, by a user at a surface of the wellbore, a shape, a size, and a location of the pre-determined shape to minimize an area between the first shape and the pre-determined shape;
calculating, by the downhole tool, one or more delta values between the first shape and the adjusted pre-determined shape; and
transmitting, by a downhole transmitter, the adjusted pre-determined shape and the delta values to a processor at a surface of the wellbore.
2. The method of claim 1 , wherein selecting the pre-determined shape comprises selecting the pre-determined shape that matches the first shape.
3. The method of claim 1 , further comprising transmitting, by the downhole transmitter, a code and/or size of the pre-determined shape to the processor.
4. The method of claim 1 , further comprising transmitting, by the downhole transmitter, a magnitude and a phase of a sine-wave function to the processor.
5. The method of claim 1 , further comprising transmitting, by the downhole transmitter, a magnitude and/or a location of the pre-determined shape to the processor.
6. The method of claim 1 , further comprising transmitting the pre-determined shape, size and/or a code of the pre-determined shape, or a location of the pre-determined shape to the processor in real-time during a drilling operation or a logging operation.
7. The method of claim 1 , wherein the pre-determined shape comprises a circle, an oval, a rectangle, or an ellipse.
8. The method of claim 1 , further comprising determining the sensor data by the downhole tool at different points around a circumference of the wellbore drilled within a formation at a selected depth.
9. The method of claim 8 , further comprising assigning the delta values to a plurality of azimuthal bins, wherein each azimuthal bin corresponding to an angular sector around the circumference of the wellbore.
10. The method of claim 1 , wherein the sensor data is determined based on measurements obtained from an angle sensor incorporated within the downhole tool.
11. The method of claim 1 , wherein the sensor comprises an at-bit inclination sensor, a survey sensor, a pressure sensor, a directional sensor, or a resistivity sensor.
12. The method of claim 1 , further comprising calculating the one or more delta values by subtracting the adjusted pre-determined shape from the first shape.
13. A system, comprising:
a downhole memory;
a downhole sensor device;
a downhole tool coupled to the downhole memory and the downhole sensor device, and configured to:
obtain, from the downhole sensor device, a first shape of sensor data representing one or more characteristics of a wellbore arranged on a polar plot;
select a pre-determined shape from a set of pre-determined shapes stored in a downhole memory that matches the first shape;
impose the pre-determined shape on the first shape arranged on the polar plot;
adjust, by a user at a surface of the wellbore, a shape, a size, and a location of the pre-determined shape to minimize an area between the first shape and the pre-determined shape; and
calculate one or more delta values between the first shape and the adjusted pre-determined shape; and
a transmitter to transmit the adjusted pre-determined shape and the delta values to a processor at a surface of the wellbore.
14. The system of claim 13 , wherein the downhole sensor device is configured to collect the sensor data while the downhole sensor device is within the wellbore.
15. The system of claim 13 , wherein the transmitter is further configured to transmit a code and/or a size of the pre-determined shape to the processor via the downhole tool in real-time during a drilling operation or a logging operation.
16. The system of claim 13 , wherein the transmitter is further configured to transmit a magnitude and a phase of a sine-wave function to the processor via the downhole tool in real-time during a drilling operation or a logging operation.
17. The system of claim 13 , wherein the transmitter is further configured to transmit a magnitude and/or a location of the pre-determined shape to the processor via the downhole tool in real-time during a drilling operation or a logging operation.
18. The system of claim 13 , wherein the pre-determined shape comprises a circle, an oval, a rectangle, or an ellipse.
19. The system of claim 13 , wherein the sensor comprises an at-bit inclination sensor, a survey sensor, a pressure sensor, a directional sensor, or a resistivity sensor.
20. The system of claim 13 , wherein the downhole tool is further configured to calculate the one or more delta values by subtracting the adjusted pre-determined shape from the first shape.