The Design Of Metrological Verification System In Automatic Weather Stations

Meteorological measurement sector needs timing verification and calibration of meteorological sensors to ensure the accuracy. With the continuous development of China’s meteorological service, higher request was put forward by society for metrological verification of automatic weather stations.Because of the defects and deficiencies of verification technology, this study puts forward a kind of calibration system of weather sensor which is based on wireless network. In addition to the calibration of automatic weather stations, this paper designs a handheld calibration.The metrological verification system of automatic weather station is divided into two parts. One part is the verification system based on wireless sensor network, the wireless sensor network based on Zigbee is created for the verification system. The goal is to realize the transmission of the meteorological elements data by wireless. The coordinator will receive the data which is transferred through the upper machine for data analysis and processing.The system will also do the judgment whether they are qualified for the system, and after that,it will generate and print the verification certificate. At the same time, the qualified data will be saved to the database so that we can query and archive it. And the other is the research of the handheld calibration, it makes the use of ZigBee technology for automatic collection of standards and on-site meteorological instrumentation readings. Meanwhile it uses the ARM processor for hardware design and language C#in the development environment of the Visual Studio2005for software design. At last, all will be transplanted into Windows CE operating system.First of all, this study introduces the techniques used by the system, and then analyses the functions and features of the verification system, and explains the regulation of verification in details. Based on this, this paper gives the overall design of the system. The software and hardware of the system will be showed detail in this study. Making use of the CC2530wireless sensor network chip, and with meteorological sensors to real-time acquisition of meteorological elements. The focal point of the paper is to explain the implementation and test process of the functional modules. And part of the program code will be seen in this paper. Secondly; the paper designs the overall design of the handheld system and provides the circuit diagram about the S3C2440processor. Even more, this paper introduces the development process and the construction of embedded operating system, the design of calibration function, the deployment, transplantation of application and so on. Lastly, this paper does the analyses of uncertainty about the temperature,relative humidity,wind velocity,rainfall and air pressure.The realization of the verification system based on wireless network greatly reduces the labor, human error and shortens the verification cycles, in all, it raises the working efficiency. And at the same time, handheld calibration has the feature of low cost and is easy to use. The use of the equipment which has good practicability is convenient for Field calibration.