| 摘要 |
An apparatus and method for reducing crosstalk and other noise sources in downhole tools is disclosed. Due to confined space in the downhole tool environment and the fact that the transmit path utilizes significantly more electrical power than the receive path, electromagnetic noise easily couples between adjacent circuitry. The specification discloses a phase- reversal element that can selectively allow the received signal to pass unaffected, or which can cause a phase reversal of the received signal. A digital signal processor samples the received signal, whi ch after receipt but before sampling has noise induced thereon. Thereafter, the digital signal processor samples the phase reversed received signal, which likewise has the noise induced thereon after receipt but before sampling. Subtracting the first sampled signal from the second produc es a resultant signal in which the noise is substantially reduced.
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