Abstract: A drilling system and a method of drilling a wellbore in an earth formation. A first antenna is disposed at a first location near a drill string. A second antenna is disposed at a second location of the drill string. The first antenna has a first specific moment. One of the first antenna and the second antenna is operated as a transmitter that transmits a transmitted signal, and the other is operated as a receiver that receives a received signal in response to the transmitted signal. The processor determines a property of an earth formation from the received signal.

Abstract: A drilling system and a method of drilling a wellbore in an earth formation. A first antenna is disposed at a first location near a drill string. A second antenna is disposed at a second location of the drill string. The first antenna has a first specific moment. One of the first antenna and the second antenna is operated as a transmitter that transmits a transmitted signal, and the other is operated as a receiver that receives a received signal in response to the transmitted signal. The processor determines a property of an earth formation from the received signal.

Abstract: Systems, methods, and devices for evaluation of an earth formation intersected by a borehole using a logging tool. Methods include performing EM logging in a borehole intersecting an earth formation using a measurement signal from an antenna system in the borehole, the measurement signal dependent upon a parameter of interest of the formation and at least one antenna system parameter of the antenna system, comprising feeding a calibration signal into a signal path of the antenna system to generate a resultant signal; estimating at least one value of the at least one antenna system parameter by using the resultant signal; and performing further logging operations in dependence upon the at least one value of the at least one antenna system parameter. The calibration signal comprises at least two calibration subsignals with a first calibration subsignal having a first frequency and a second calibration subsignal having a second frequency.

Abstract: A system for determining bending of a drilling tool includes at least one element attached to the drilling tool and the at least one element includes a magnetic material, and at least one electrical conduit in the drilling tool and electro-magnetically coupled to the at least one element. The system also includes at least one signal source that feeds a signal into the electrical conduit and a measurement system that: measures at least one property of the signal in the electrical conduit as the signal source feeds the signal; and determines the bending of the drilling tool based on the measured property of the signal.

Abstract: A method to measure a parameter of interest is provided. The method includes receiving a first signal via an antenna of a reception circuit. The method further includes generating a second signal by a signal generator of the reception circuit. The method further includes mixing the first signal and the second signal in a mixer of the reception circuit to generate a third signal. The method further includes measuring a parameter of the third signal using an instrument. The method further includes adjusting, by a processor, a frequency of the second signal to substantially match a frequency of the first signal based at least in part on the measured parameter of the third signal. The method further includes determining, by the processor, the parameter of interest using the adjusted frequency of the second signal.

Abstract: Systems, methods, and devices for evaluation of an earth formation intersected by a borehole using a logging tool. Methods include performing EM logging in a borehole intersecting an earth formation using a measurement signal from an antenna system in the borehole, the measurement signal dependent upon a parameter of interest of the formation and at least one antenna system parameter of the antenna system, comprising feeding a calibration signal into a signal path of the antenna system to generate a resultant signal; estimating at least one value of the at least one antenna system parameter by using the resultant signal; and performing further logging operations in dependence upon the at least one value of the at least one antenna system parameter. The calibration signal comprises at least two calibration subsignals with a first calibration subsignal having a first frequency and a second calibration subsignal having a second frequency.

Abstract: A system for determining bending of a drilling tool includes at least one element attached to the drilling tool and the at least one element includes a magnetic material, and at least one electrical conduit in the drilling tool and electro-magnetically coupled to the at least one element. The system also includes at least one signal source that feeds a signal into the electrical conduit and a measurement system that: measures at least one property of the signal in the electrical conduit as the signal source feeds the signal; and determines the bending of the drilling tool based on the measured property of the signal.

Abstract: A method to measure a parameter of interest is provided. The method includes receiving a first signal via an antenna of a reception circuit. The method further includes generating a second signal by a signal generator of the reception circuit. The method further includes mixing the first signal and the second signal in a mixer of the reception circuit to generate a third signal. The method further includes measuring a parameter of the third signal using an instrument. The method further includes adjusting, by a processor, a frequency of the second signal to substantially match a frequency of the first signal based at least in part on the measured parameter of the third signal. The method further includes determining, by the processor, the parameter of interest using the adjusted frequency of the second signal.

Abstract: Systems, methods, and devices for evaluation of an earth formation intersected by a borehole using a logging tool. Methods include performing EM logging in a borehole intersecting an earth formation using a measurement signal from an antenna system in the borehole, the measurement signal dependent upon a parameter of interest of the formation and at least one antenna system parameter of the antenna system, comprising feeding a calibration signal into a signal path of the antenna system to generate a resultant signal; estimating at least one value of the at least one antenna system parameter by using the resultant signal; and performing further logging operations in dependence upon the at least one value of the at least one antenna system parameter. The calibration signal comprises at least two calibration subsignals with a first calibration subsignal having a first frequency and a second calibration subsignal having a second frequency.

Abstract: An apparatus for measuring resistivity in a borehole includes first and second modules configured to be conveyed through the borehole and a transmitter connected to the first module, the transmitter transmitting a transmitter signal that causes a field signal to be created in a formation surrounding the borehole. The apparatus also includes a receiver connected to the second module configured to sense the field signal, a reflection generator and a delay determination circuit that includes a pulse generator and a timer. The apparatus also includes a communication link coupling the delay determination circuit and the reflection generator. The delay determination circuit causes a first pulse to be transmitted to the reflection generator and determines an indication that is related to the time until a reflection is received back from the reflection generator.

Abstract: An apparatus for measuring resistivity in a borehole includes first and second modules configured to be conveyed through the borehole and a transmitter connected to the first module, the transmitter transmitting a transmitter signal that causes a field signal to be created in a formation surrounding the borehole. The apparatus also includes a receiver connected to the second module configured to sense the field signal, a reflection generator and a delay determination circuit that includes a pulse generator and a timer. The apparatus also includes a communication link coupling the delay determination circuit and the reflection generator. The delay determination circuit causes a first pulse to be transmitted to the reflection generator and determines an indication that is related to the time until a reflection is received back from the reflection generator.

Abstract: Method and apparatus for transmitting a first data set from a tool to a receiver are provided. The method includes: obtaining a first plurality of measurements using the tool to form a first dataset; saving data from the first plurality of measurements that form the first dataset in non-volatile memory; transmitting first data-groups derived from the first dataset to the receiver, each of the first data-groups comprising different measurements of the formation; and storing in the non-volatile memory a storage position of a last transmitted first data-group. Upon restoration of a loss of communications that prevents transmission of all the first data-groups, determining the storage position of the last transmitted first data-group; and continuing the transmission of the first data-groups from the storage position of the first data-group last transmitted before the loss of communications.