Dynamic data transmission technology for expendable current profiler based on low-voltage differential signaling
- 1Key Laboratory of Geo-detection, China University of Geosciences, Beijing, Ministry of Education, Beijing, P.R. China
- 2School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, P.R. China
Abstract. A dynamic data transmission technology for expendable current profilers (XCPs) is proposed in this paper. Two parallel varnished wires are employed as the data transmission medium. By testing the transmission properties of the varnished wires, a baseband transmission system is studied and designed. Modified low-voltage differential signaling (LVDS) is adopted as the physical layer for data transmission. The data transmission protocol is modified and optimized in accordance with the RS-232 protocol, and the Manchester code is superimposed. According to the results of indoor and marine tests, the data transmission distance of the designed system, which employs a 0.1 mm diameter varnished wire, extends to 2 km with high efficiency and accuracy for data transmission, exhibiting excellent performance. Moreover, this data transmission technology could be used for other expendable marine-environment parametric measuring instruments such as an expendable bathythermograph and an expendable conductivity temperature depth profiler.