水下XCTD剖面仪传输线间分布电容的建模与计算

Modeling and calculation of distributed capacitance between the transmission lines of underwater XCTD profiler

由于XCTD(抛弃式盐温深)剖面仪下沉到一定深度后信号传输严重失真,传输电缆动态展开后的线间电容对信号的完整性传输的破坏性越来越大。根据具体应用环境建立了XCTD电缆电容计算模型,然后从理论上建立了平行电缆电容和偏心电缆电容的数学公式,最后采用Comsol Multiphysics进行建模仿真。结果表明,理论计算验证了Comsol平行电缆电容仿真模型的正确性,并进一步采用该方法计算出更为复杂的水下电缆的电容值,其对分析我国自主研发的XCTD剖面仪深水信道信号传输完整性具有重要的参考价值,为该课题的深入研究提供了一种全新的建模方法。

For signal transmission will be caused serious distortion after XCTD （Expendable Conductivity Temperature and Depth）profiler sink to a certain depth. With transmission cable dynamic swinging,the line capacitance increasingly affects signal＇s complete transmission. The paper is aimed at the environment of specific applications and establishes the calculation model of the XCTD capacitance of cable. Then the capacitance of parallel and eccentric cable＇s mathematical formulas capacitance is established theoretically. Finally use Comsol Multiphysics to simulate. The test result shows that the Comsol simulation model of the parallel cable＇s capacitance proved to be right in theory. Furthermore, we use this method to calculate more complex capacitance value of underwater cable. It is importantly valuable for analyzing the channel signal transmission＇s integrity using the XCTD under deep water that is researched and developed independently by the Chinese 863 plan ,and providing a new modeling method for this topic research.