摘要 |
In one aspect, an apparatus for use in a wellbore is disclosed that in one embodiment includes an electrically-conductive member having an outer and/or inner surface coated with an electrically-insulating material, a transmitter placed at a first location on the electrically- conductive member that induces electromagnetic wave signals that travel along the coated surface of the electrically conductive member, and a receiver placed at a second location spaced from the first location on the electrically-conductive member that detects the electromagnetic induced by the transmitter. |