Abstract: A gimbal sensor platform positionable in a tool body includes an inner gimbal and an outer gimbal. The inner gimbal is rotatably coupled to the outer gimbal, and the outer gimbal is rotatably coupled to the tool body. The inner and outer gimbals may each be rotated by an angular positioning device. A gyro or other sensor may be coupled to the inner gimbal. The gyro or other sensor may be reoriented by rotating the outer gimbal, the inner gimbal, or both.

Abstract: A method for transmitting data from a MWD system at the BHA of a drill string may include transmitting the data in a MWD signal from the MWD system. The MWD signal may be modulated at a position closer to the surface onto a mud pulse modulated signal. The mud pulse modulated signal may be generated by a downhole friction reducing device. The downhole friction reducing device may include a mud motor. The mud motor may create pressure pulses based on its speed of rotation. The downhole friction reducing device may include a modulating valve. The modulating valve may be electromechanically or mechanically operated. The modulated signal may be detected at the surface by a receiver using one or more pressure or flow sensors. The receiver may use one or more harmonics of the modulated signal to receive the data.

Abstract: A method of interpreting a signal transmitted through a drilling fluid disposed within a telemetry channel of a wellbore that includes defining a finite number of distinct message signals for representing conditions within the wellbore. The method also includes transmitting one of the message signals through the telemetry channel, and receiving a distorted signal that includes the message signal as distorted by transmission through the telemetry channel. A channel impulse response is estimated and applied to at least one of the message signals to generate at least one predicted signal. A comparison is made between the predicted signal and the distorted signal, and an estimation is made as to which of the finite number of message signals is included in the distorted signal based on the comparison.

Abstract: A method for transmitting data from a MWD system at the BHA of a drill string may include transmitting the data in a MWD signal from the MWD system. The MWD signal may be modulated at a position closer to the surface onto a mud pulse modulated signal. The mud pulse modulated signal may be generated by a downhole friction reducing device. The downhole friction reducing device may include a mud motor. The mud motor may create pressure pulses based on its speed of rotation. The downhole friction reducing device may include a modulating valve. The modulating valve may be electromechanically or mechanically operated. The modulated signal may be detected at the surface by a receiver using one or more pressure or flow sensors. The receiver may use one or more harmonics of the modulated signal to receive the data.

Abstract: A gimbal sensor platform positionable in a tool body includes an inner gimbal and an outer gimbal. The inner gimbal is rotatably coupled to the outer gimbal, and the outer gimbal is rotatably coupled to the tool body. The inner and outer gimbals may each be rotated by an angular positioning device. A gyro or other sensor may be coupled to the inner gimbal. The gyro or other sensor may be reoriented by rotating the outer gimbal, the inner gimbal, or both.

Abstract: A method for transmitting data from a MWD system at the BHA of a drill string may include transmitting the data in a MWD signal from the MWD system. The MWD signal may be modulated at a position closer to the surface onto a mud pulse modulated signal. The mud pulse modulated signal may be generated by a downhole friction reducing device. The downhole friction reducing device may include a mud motor. The mud motor may create pressure pulses based on its speed of rotation. The downhole friction reducing device may include a modulating valve. The modulating valve may be electromechanically or mechanically operated. The modulated signal may be detected at the surface by a receiver using one or more pressure or flow sensors. The receiver may use one or more harmonics of the modulated signal to receive the data.

Abstract: A gimbal sensor platform positionable in a tool body includes an inner gimbal and an outer gimbal. The inner gimbal is rotatably coupled to the outer gimbal, and the outer gimbal is rotatably coupled to the tool body. The inner and outer gimbals may each be rotated by an angular positioning device. A gyro or other sensor may be coupled to the inner gimbal. The gyro or other sensor may be reoriented by rotating the outer gimbal, the inner gimbal, or both.

Abstract: A method for transmitting data from a MWD system at the BHA of a drill string may include transmitting the data in a MWD signal from the MWD system. The MWD signal may be modulated at a position closer to the surface onto a mud pulse modulated signal. The mud pulse modulated signal may be generated by a downhole friction reducing device. The downhole friction reducing device may include a mud motor. The mud motor may create pressure pulses based on its speed of rotation. The downhole friction reducing device may include a modulating valve. The modulating valve may be electromechanically or mechanically operated. The modulated signal may be detected at the surface by a receiver using one or more pressure or flow sensors. The receiver may use one or more harmonics of the modulated signal to receive the data.

Abstract: A method for transmitting data from a MWD system at the BHA of a drill string may include transmitting the data in a MWD signal from the MWD system. The MWD signal may be modulated at a position closer to the surface onto a mud pulse modulated signal. The mud pulse modulated signal may be generated by a downhole friction reducing device. The downhole friction reducing device may include a mud motor. The mud motor may create pressure pulses based on its speed of rotation. The downhole friction reducing device may include a modulating valve. The modulating valve may be electromechanically or mechanically operated. The modulated signal may be detected at the surface by a receiver using one or more pressure or flow sensors. The receiver may use one or more harmonics of the modulated signal to receive the data.

Abstract: A gimbal sensor platform positionable in a tool body includes an inner gimbal and an outer gimbal. The inner gimbal is rotatably coupled to the outer gimbal, and the outer gimbal is rotatably coupled to the tool body. The inner and outer gimbals may each be rotated by an angular positioning device. A gyro or other sensor may be coupled to the inner gimbal. The gyro or other sensor may be reoriented by rotating the outer gimbal, the inner gimbal, or both.

Abstract: A method for transmitting data from a MWD system at the BHA of a drill string may include transmitting the data in a MWD signal from the MWD system. The MWD signal may be modulated at a position closer to the surface onto a mud pulse modulated signal. The mud pulse modulated signal may be generated by a downhole friction reducing device. The downhole friction reducing device may include a mud motor. The mud motor may create pressure pulses based on its speed of rotation. The downhole friction reducing device may include a modulating valve. The modulating valve may be electromechanically or mechanically operated. The modulated signal may be detected at the surface by a receiver using one or more pressure or flow sensors. The receiver may use one or more harmonics of the modulated signal to receive the data.

Abstract: A method of interpreting a signal transmitted through a drilling fluid disposed within a telemetry channel of a wellbore that includes defining a finite number of distinct message signals for representing conditions within the wellbore. The method also includes transmitting one of the message signals through the telemetry channel, and receiving a distorted signal that includes the message signal as distorted by transmission through the telemetry channel. A channel impulse response is estimated and applied to at least one of the message signals to generate at least one predicted signal. A comparison is made between the predicted signal and the distorted signal, and an estimation is made as to which of the finite number of message signals is included in the distorted signal based on the comparison.