The research methods of a time-varying channel model of the XCTD profiler

Abstract

The expendable conductivity-temperature-depth (XCTD) profiler is often used for ocean depth measurement and uses an enameled wire transmission channel. However, the changing impedance characteristics of the dynamic real-time channel affect the stability of the signal transmission. In this paper, we study the XCTD of China, using a deep-sea abandoned measuring instrument transmission channel as the original model, we present: (a) a method for establishing a time-varying channel model; (b) accurate computation of the transmission cable and spool cable distributed capacitance, winding inductance and distributed resistance; (c) a discussion on the impedance values generated by the coupling effect of seawater. The establishment of the channel transfer function model illustrates the effects of the time-varying channel on the signal transmission performance and can improve the signal transmission capacity by providing a theoretical basis for analysis of the XCTD channel.