Study on Dynamic Data Transmission Technology for Expendable Current Profiler

Abstract. Expendable Current Profilers (XCPs) play a crucial role in global ocean parameter detection and deep-sea physical oceanography research. However, affected by the complex seawater environment and the dynamic impedance changes of enamelled wires during probe deployment, such expendable devices face bottlenecks in long-distance dynamic data transmission. Specifically, they suffer from high transmission bit error rates (approximately 10⁻²), limited transmission distances (around 1 km), and low transmission rates (2400 baud or 4800 baud). These issues severely restrict their development and practical application. To address the aforementioned bottlenecks, this study conducted targeted research focusing on the optimization of data transmission technology. It effectively reduced transmission interference by optimizing the analog circuit design for Low-Voltage Differential Signaling (LVDS) data transmission. Additionally, RS encoding technology was added to the digital board of the probe to lower the transmission bit error rate. Experimental verification shows that the optimized system can achieve data transmission over a distance of 2500 meters using a double-coated enamelled wire with a diameter of 0.1 mm. The data transmission rate is increased to 9600 baud, and the bit error rate is reduced to 10⁻⁴, resulting in a significant improvement in overall performance. Furthermore, the system operates stably and reliably, with all functions meeting the preset design requirements, laying a foundation for subsequent practical marine applications.