摘要 |
An apparatus for utilizing a pre-existing telemetry transmitter near a drill bit for transmitting or receiving signals to make measurements of surrounding formation resistivity includes a drill collar, at least two toroidal receiving antennas deployed on the drill collar and spaced at an axial distance from each other for receiving or transmitting signals from or to the telemetry transmitter, at least two receiver modules coupled to the toroidal receiving antennas for processing signals received or to be transmitted from or to the telemetry transmitter and adjusting frequency the receiver modules work at, and a converting module coupled to the receiver modules. The converting module includes a microprocessor for calculating the surrounding formation resistivity and controlling the frequency tuners in the receiver modules. A corresponding method for utilizing a multiple dimensional conversion chart to convert data of measured flow-out current through the formation into data of formation resistivity is also provided. |