Small Watershed Flash Flood Warning System Embedded Data Gathering Platform Design

China is a mountainous country, about two-thirds of the land has hilly and mountain, topography is complicated and varied. The monsoon climate determines the rainfall uneven distribution during the year in China, the heavy rains happen frequently and flood season concentrate highly. The flash floods threat people who live in the1836county-level administrative regions. Due to frequently heavy rains, complex topography and human economic activities, China has become one of most seriously affected countries by flash floods disaster.In recent years, with the development of electronic technology, computer technology and sensor technology, wireless sensor network technology has been widely used in environmental monitoring. This paper designs embedded data aggregation platform which is a part of wireless sensor networks flash flood monitoring system to realize some functions such as real-time aggregating small basin water level, rainfall and other monitoring data, data resolution, water and rainfall information consistency judgment, data sending through the GPRS to the remote back-end data center and so on. Study flash flood warning model and give a determining method for flash flood warning alert value through sorting out the basin information, then use BP neural network technology to complete the fitting of the water level and flow data, at last forecast flash floods whether occur by using D-S evidence theory.This article select powerful ARM9processor S3C2440as the hardware platform, integrated RF communication module, power module, JTAG interface module, GPRS communication module, LCD display module, Ethernet module, serial module, etc. This paper uses ZigBee protocol transmits data between data aggregation platform the and water rainfall sensor nodes, ZigBee module communicate with processor by serial RS232. Data aggregation platform use GPRS/Internet transmission mode, it will send aggregation data to the remote. On writing software, this paper use multi-threaded programming and fully consider the interaction with customers. Finally, this paper complete the interface design such as node control interface, flash flood monitoring data display interface, help, etc.After hardware and software debugging and improvement, this system can run stability in the wild, the practice shows that the system collects data timely, accurately, and reliability, embedded data aggregation platform is easy to install and use, which is suitable to apply for the wild environmental water and rainfall monitoring. It realizes automation and unattended monitoring, which has extensive practical applications.