Downhole sensor interrogation employing coaxial cable

摘要

The present invention is directed to methods and systems for oil field downhole sensing and communication during drilling and/or production, wherein such methods and systems utilize coaxial cable to transmit electromagnetic (EM) energy, continuously or as a pulse, to passive downhole sensors.

主权项

1. A system for interrogating a downhole environment in a casing-lined borehole beneath a surface, said system comprising:
a source of electromagnetic energy positionable at the surface and operable for generation of an electromagnetic energy signal; a sensor module, the sensor module comprising a passive resonating circuit that, during use and when positioned in the downhole environment, modulates the electromagnetic energy signal in response to an environmental condition in the downhole environment; and a coaxial transmission cable, electrically insulated from the casing of the borehole, and in electrical communication with the source and the sensor module.