Abstract: A method of signal processing includes providing at least a first pressure sensor and a second pressure sensor spaced in a drilling system and using an algorithm to separate the downwardly propagating waves from the upwardly propagating waves. In one or more examples, an algorithm may include determining a velocity of pressure signals in a wellbore, time-shifting and stacking pressure signals from at least the first pressure sensor and the second pressure sensor to determine a downwardly propagating noise signal, and subtracting the downwardly propagating noise signal from at least the signal from the first pressure sensor.

Abstract: An electromagnetic logging tool is disclosed that includes a support; and at least one four-coil array disposed on the support, wherein the at least one four-coil array comprises: a transmitter, a bucking coil, a receiver, and a trim coil. A method for balancing an induction array is disclosed that includes applying an alternating current to a transmitter of the induction array that comprises the transmitter, a bucking coil and a receiver; measuring a mutual coupling between the transmitter and the receiver; and adding an extra bucking coil, if the mutual coupling exceeds a selected criterion.

Abstract: A connector connects auxiliary flow lines and electrical lines that extend through and terminate at or near opposing ends of two respective components of a downhole tool string. The connector comprises a body assembly for fluidly-connecting the auxiliary flow lines and electrically-connecting the electrical lines of the respective two components, and an assembly for adjusting the length of the body assembly. The two components are discrete modules of a unitary tool, or alternatively, are distinct tools. Additionally, the connector may include a mechanism for closing the auxiliary flow lines of one or both compartments upon disconnection of the fluid connection between the two components.