Downhole Resistivity Receiver with Canceling Element

摘要

A downhole tool assembly comprising at least one downhole tool string component. The downhole tool string component comprises at least one transmitter. The transmitter is attached to a primary signal generator and transmits a primary signal into the surrounding earth formation. The primary signal creates an induced or reflected signal within the formation which may reveal information regarding the formation. The downhole tool string component also comprises at least one receiver. The receiver is adapted to measure the signal induced or reflected in the formation. The downhole tool sting component also comprises at least one active coil or piezoelectric transducer proximate the receiver. The active coil or piezoelectric transducer is adapted to substantially cancel the primary signal generated by the transmitter and allow the receiver to focus on the induced or reflected signal.