Design And Implementation Of Automatic Monitoring System Of Water And Rainfall Based On Beidou Satellite And GPRS Dual Communication Channel

Automatic monitoring system of water and rainfall uses multiple technologies of sensing,communication, networking, electronics, computer and hydrology to perform the precipitationand water level data real-time acquisition, transmission and processing in river basin.In "5-12" Wenchuan earthquake, Qingchuan encountered a heavy hit. In order to ensure safetyof life and property of Qingchuan people, carry out post-disaster restoration and reconstructionwork smoothly, the post-disaster reconstruction headquarters and Qingchuan people’s governmentdecided to establish the Qingchuan Water and Rainfall Warning System, and the automaticmonitoring system of water and rainfall is the key part of it.Based on the special geographical environment of Qingchuan, and relatively weak level ofmobile communications condition after the disaster. In order to improve the reliabilitycommunication on the automatic monitoring station of water and rainfall, and reduce the projectmaintenance costs, the paper analyzes currently used in several communication, and presents theBeiDou Satellite Communication and GPRS dual-channel communications solution for theautomatic monitoring system of water and rainfall.The paper describes three components of the automatic monitoring system of water andrainfall including the automatic monitoring station of water and rainfall, BeiDou Satellite and GPRScombining networking solution and communication platform. It analyzes the detail design andrequirement in each level of them. In addition, it mentions the selection progress of equipment ofrainfall sensor and water level sensor and Beidou satellite communication terminal. Furthermore,this paper presents that after analyzing the characteristic of combining networking of BeiDouSatellite and GPRS, the designs of the dual-channel communication network solution for theSystem is implemented, and the adjustment of data process of communication platform isperformed according to the dual-channel transmission characteristic. This paper introduces theresearches on the communication frequency control strategy, power control strategy, and messageformat which impact the BeiDou Satellite and GPRS dual-channel communication, and implementation of the requirement of BeiDou Satellite and GPRS dual-channel combiningnetworking communication. More over, it shows the completion the development on RTU and theterminal communication platform working on dual-channel communication mode, andimplementation of building a complete automatic monitoring system of water and rainfall based onBeiDou Satellite and GPRS dual-channel combining networking communication.The Qingchuan Water and Rainfall Warning System is delivery in May20,2010, and it playeda key role both on "20100813" and "20100818" floods. All the automatic monitoring station ofwater and rainfall worked properly during the floods, as the water and rainfall information areunimpeded transmitted under the BeiDou Satellite Communication and GPRS dual-channelcommunication solution.