Communication System for Single-Core Cable in 10,000-Meter Deep Wells Based on Dynamic Impedance Matching and Adaptive Decoding

The development of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{1 0, 0 0 0}$</tex>-meter deep wells faces extreme environmental challenges, such as high temperatures over 200° C and high pressures over 150 MPa. Dynamic changes in cable parameters and transient pulse noise generated by subsurface electric pumps lead to severe signal attenuation, phase shift, and electromagnetic interference. Additionally, deep-well communication requires independent control of seven layers, and a single-node failure can affect the entire communication system. This paper proposes a solution based on dynamic impedance matching and adaptive decoding. In terms of hardware, a dualwinding magnetic ring structure is used to adjust impedance in real time. In terms of algorithms, a combination of a three-stage operational amplifier cascade and deep learning-based noise compensation technology is employed to enhance the robustness of the communication system. Laboratory tests show that under conditions of 150° C, the impedance matching error is less than 3 %, and the signal-to-noise ratio(SNR)is increased from 15 dB to 38 dB. In the Tarim Oilfield, a 10,910-meter deep well test revealed a bit error rate(BER)of only 0.68 %, significantly lower than the traditional solution's <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{7. 9 2 \%}$</tex>. The control delay for seven layers was reduced from 520 ms to 48 ms. The system has been widely applied in the Daqing and Tarim oilfields, with single-well measurement and adjustment time shortened by 89 %, and installation costs reduced by <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{4 2 \%}$</tex>. The system has significantly improved the efficiency of deep-well development and provided new ideas for communication technology in extreme environments.