摘要 |
A downhole telemetry system having a surface transceiver, a cable, and a downhole transceiver coupled to the surface transceiver via the cable. The surface transceiver isolates an uplink signal from a combined uplink/downlink signal on the cable using time-domain signal cancellation. The downhole transceiver isolates a downlink signal from the combined uplink/downlink signal using time-domain signal cancellation. In the surface transceiver, the time-domain signal cancellation may be performed by running the combined uplink/downlink signal through a coil of a transformer while running a copy of the downlink signal through an opposite coil of the transformer. Likewise, in the downhole transceiver, the time-domain signal cancellation may be performed by running the combined uplink/signal through a coil of a transformer while running a copy of the uplink signal through an opposite coil of the transformer.
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