摘要 |
<p>Apparatus and method for transmitting data in a borehole (10) between a downhole installation including one or more tools (20) (for example downhole testing tools) and a surface installation (62), wherein the downhole installation is connected to the surface installation by means of a tubular conduit (such as a drill string or production tubing 14) ). The apparatus comprises: an acoustic modem (26) associated with each tool, the modem acting to convert tool signals such as electrical tool signals into acoustic signals; and a hub (90) forming part of the downhole installation to which the tools and tubular conduit are connected and comprising an acoustic receiver (74) and an electromagnetic transmitter (80). The acoustic modems operate to generate acoustic signals in the downhole installation representative of the tool signals, the acoustic signals passing along the downhole installation to be received at the acoustic receiver of the hub, the received acoustic signals being used to operate the electromagnetic transmitter to transmit electromagnetic signals to the surface for reception at the surface installation.</p> |