An electromagnetic borehole telemetry system providing improved signal to noise ratio. Adaptive filters use noise channels as references to remove noise from the signal channel. Directional detectors provide a signal channel with reduced noise content and improved noise channels with reduced signal content....http://www.google.fr/patents/US7268696?utm_source=gb-gplus-shareBrevet US7268696 - Directional signal and noise sensors for borehole electromagnetic telemetry system
Directional signal and noise sensors for borehole electromagnetic telemetry ...
