| 摘要 |
<p>A drill stem communication system for transmitting data between downhole and uphole locations in a borehole includes at least one transducer (40, 40') at a first location on a drill stem (18) for modulating motion and/or stress in the drill stem (18), and at least one transducer (42') at a second location on the drill stem (18) for detecting the modulation. Control devices (36, 260, 312, 382) may be provided at both locations for establishing communication therebetween.</p> |
