This paper explores the feasibility of applying the capacitive power transfer (CPT) technology in underground data transmission applications. Based on the electrical properties of soils, the paper extends the existing CPT air coupler model into a more generalized model. The autonomous push-pull inverter is selected to power the CPT system and modified to further the data transmission range. With a designed load shift keying (LSK) circuitry, this self-oscillating inverter regards the data as a sequence of impedance changes, resulting in operation frequency drifts. A Frequency Shift Keying (FSK) demodulator is applied to capture the frequency variations and recover back to data. The proposed design has been simulated, verified, and implemented on a complete prototype. Various testings have been carried out, and the results are satisfactory.

中文翻译：

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使用电容式数据传输设备的地下通信

本文探讨了在地下数据传输应用中应用电容性功率传输（CPT）技术的可行性。基于土壤的电学特性，本文将现有的CPT空气耦合器模型扩展为更通用的模型。选择自主推挽式逆变器为CPT系统供电，并对其进行修改以进一步扩展数据传输范围。通过设计的负载移位键控（LSK）电路，该自激式逆变器将数据视为一系列阻抗变化，从而导致工作频率漂移。移频键控（FSK）解调器用于捕获频率变化并恢复为数据。拟议的设计已在完整的原型上进行了仿真，验证和实施。已经进行了各种测试，结果令人满意。