公开(公告)号：CA2628997A1

公开(公告)日：2008-10-13

申请号：CA2628997

申请日：2008-04-11

Applicant: XACT DOWNHOLE TELEMETRY INC

Inventor： NEFF JAMES M ,  CAMWELL PAUL L ,  LOGAN DEREK W

IPC: E21B47/12

Abstract: A method is provided which transmits information using a plurality of data transmission nodes situated along a drill string. In this method, a first node obtains a transmission status of a second node. When the transmission status of the second node indicates that the second node meets a selected performance threshold, information is sent from the first node to the second node. When the transmission status of the second node indicates that the second node does not meet its performance threshold, then the first node obtains a transmission status of a third node. When the transmission status of the third node indicates that the third node meets a selected performance threshold, information is transmitted from the first node to the third node for relaying along the drill string.

公开(公告)号：CA2585044C

公开(公告)日：2013-09-17

申请号：CA2585044

申请日：2007-04-10

Applicant: XACT DOWNHOLE TELEMETRY INC

Inventor： CAMWELL PAUL L ,  SIEMENS WENDALL L ,  LOGAN DEREK W

IPC: E21B47/16 ,  E21B47/12

Abstract: A system and method of closed loop control whereby acoustic telemetry devices, both at surface and downhole, form nodes of a feedback loop; said feedback loop enables an automatic and dynamic means to modify transmission parameters such that the system's telemetry data rate is maximized consistent with minimum achievable signal-to-noise ratio and minimum expended power.

公开(公告)号：CA2585044A1

公开(公告)日：2007-10-11

申请号：CA2585044

申请日：2007-04-10

Applicant: XACT DOWNHOLE TELEMETRY INC

Inventor： CAMWELL PAUL L ,  LOGAN DEREK W ,  SIEMENS WENDALL L

IPC: E21B47/16 ,  E21B47/12

Abstract: A system and method of closed loop control whereby acoustic telemetry device s, both at surface and downhole, form nodes of a feedback loop; said feedback loop enables an automatic and dynamic means to modify transmission parameters such that the system's telemetry data rate is maximized consisten t with minimum achievable signal-to-noise ratio and minimum expended power.

公开(公告)号：CA2628997C

公开(公告)日：2015-11-17

申请号：CA2628997

申请日：2008-04-11

Applicant: XACT DOWNHOLE TELEMETRY INC

Inventor： CAMWELL PAUL L ,  NEFF JAMES M ,  LOGAN DEREK W

IPC: E21B47/12

Abstract: A method is provided which transmits information using a plurality of data transmission nodes situated along a drill string. In this method, a first node obtains a transmission status of a second node. When the transmission status of the second node indicates that the second node meets a selected performance threshold, information is sent from the first node to the second node. When the transmission status of the second node indicates that the second node does not meet its performance threshold, then the first node obtains a transmission status of a third node. When the transmission status of the third node indicates that the third node meets a selected performance threshold, information is transmitted from the first node to the third node for relaying along the drill string.

公开(公告)号：CA2569818C

公开(公告)日：2013-08-13

申请号：CA2569818

申请日：2006-12-01

Applicant: XACT DOWNHOLE TELEMETRY INC

Inventor： DRUMHELLER DOUGLAS S ,  CAMWELL PAUL L ,  DOPF ANTHONY R ,  LOGAN DEREK W

IPC: G10K11/16 ,  G10K11/18 ,  G10K11/20

Abstract: An acoustic isolator for use with tubular assemblies such as drillpipe or production tubing comprising an acoustic wave transmitter, the acoustic isolator comprising, in series, an odd integer ~/4 multiple tuning bar of first acoustic impedance adjacent the acoustic wave transmitter, an odd integer ~/4 multiple reflector tube of second acoustic impedance, and a snubber of third acoustic impedance, wherein there is an acoustic impedance mismatch between the odd integer ~/4 multiple tuning bar and the odd integer ~/4 multiple reflector tube and an acoustic impedance mismatch between the odd integer ~/4 multiple reflector tube and snubber, such that a "down" wave propagated toward the isolator is reflected back substantially in phase with an "up" wave propagated from the acoustic wave source away from the isolator. Furthermore, the acoustic isolator is similarly effective in reflecting "up" propagating waves originating from below the isolator, hence further protecting the acoustic wave source from possible deleterious interference.