Patent ID: 6268731
Filing Date: 2001-07-31
Classification: G01V

Abstract:
A locator for an electrically conducting underground object which generates an alternating electromagnetic field, said locator having first, second and third spaced apart antennas and processing means, first, second, third and fourth electromagnetic field detectors, the first and second field detectors measure electromagnetic field components in a direction perpendicular to the direction of separation of the first and second antennas, the third field detector measures the electromagnetic field components parallel to the direction of separation of the first and second antennas, and the fourth field detector measures the electromagnetic field components in a direction mutually perpendicular to the directions of the electromagnetic field components measured by the first, second and third detectors; and the first antenna is formed by said first and third electromagnetic field detectors, the second antenna is formed by the second electromagnetic field detector, and the third antenna is formed by the fourth electromagnetic field detector, and at least one of said antennas measures an electromagnetic field component in a direction not measured by at least one of the other antennas.