Coastal Station Pressure-type Tide-level Monitoring System

The 21th century is the century of ocean. Faced with the fact that land resources are gradually decreasing, human beings are more and more dependent on the ocean. How to further understand the ocean and how to appropriately exploit it are issues calling for profound consideration of humans.The ocean-monitoring technology is a technique intended to assist men to better appreciate the ocean, an important means of obtaining ocean information, and the foundation of exploiting and taking advantage of it. In the field of ocean-monitoring, there are two types of measurement system according to the laying mode. One is the surface measurement system, the buoy working as the carrier; the other is the underwater measurement system based on pressure-type measurement devices.Project which the paper is based on:the coastal station pressure-type tide-level monitoring system, a sub-project of comprehensive techniques of measuring underwater flow, wave, and tide, plays an essential role in the oceanic dynamic environment real-time three-dimensional monitoring system of National 863 Project of Ocean Monitoring Technology.Design of the coastal station pressure-type tide-level monitoring system mainly accomplishes precise measurement of tide-level data, and implements data transfer and storage, satisfying requirements of clients for observing tide-level and analyzing data. What it studies includes acquisition, transfer and telecommunication and processing of tide-level data, real-time displaying of data received by the receiving interface of high quality, storage and query of data, report-generation, and analysis of historical data.The paper gives an introduction to the design scheme of the coastal station pressure-type tide-level monitoring system, with emphasis on the design of hardware and software of the master computer and processing of tide-level data. The hardware part is based on STM32F103C8T6 micro-processor, utilizes KPSI 335 water-level transducer of high-precision to measure tide-level, and sends data to the master computer through RS-485 serial interface telecommunication. Software in the master computer is written in VC++ language, and Visual Studio 2008 is adopted as the developing environment with BCGControlBar library in-built as the interface library of the whole programme. Access database is utilized in the design to implement storage and query of tide-level data. In data-processing, wavelet transform is adopted to realize data filtering and eliminate the disturbance to tide-level data coming from passing ships and wind and wave, thus resulting in a smooth curve of tide-level data.Upon finishing design of the system, a laboratory test and an oceanic test were conducted one after another, showing that the system can stably function and meet the design requirements of the tide-level measurement system.