Patent ID: 7414391

Claim:
A method for calibrating an electromagnetic logging tool having a plurality of antennas disposed thereon with at least one antenna having its axis at an angle with respect to the axis of the tool, each antenna being configured to transmit and/or receive electromagnetic energy, comprising the steps of: (a) disposing a test loop about the electromagnetic logging tool such that the axis of the tool and a plane on which the test loop lies form a tilt angle that is between about 0 and 90 degrees; (b) measuring a signal induced in one of said antennas when another of said antennas is energized, the induced signal being affected by the test loop; (c) determining a correction for the induced signal, including producing a corrected signal and comparing the corrected signal with a calculated signal based on a model including the electromagnetic logging tool and the test loop; and (d) further comprising deriving a gain or phase factor by comparing the corrected signal with the calculated signal.