Gprs-based Elements Of Automatic Weather Stations

Air pressure, air temperature, humidity, direction of wind, wind velocity, rainfall, and ground temperature are the foundation of the weather work. The automatic weather station can collect the weather's information and transmit these data automatically. The automatic weather station can provide the important information for science research, the weather information and the weather analysis. This paper discusses the advantage of the GPRS, analytical each weather main factor that the temperature that the sensor and function, air pressure compensates the method, the temperature parameter to turn, reliability etc. the key problem. The automatic weather station was designed, which is based on GPRS. It realized the automation and networks of the weather collection.The GPRS is the brief name of General Packet Radio Service, which is one of the contents of the GSM Phase2.1.Compare the GPRS data service with method of GSM, except the characteristics of the " high speed"," on-line forever", the GPRS still have the inexpensive advantage of the communication expenses.Sensor is important part of the measure system. In this paper, firstly each interface of sensor and functions was analyzed, which is the foundation of electronic circuit and the processing software.In the part of the electric circuit design, the main processor is AD μC812, the inner part there is 12 bits A/ D conversion. Each sensor adjust circuit was designed, detailed analyzed the platinum resistance to measure the constant current may cause the error margin to flow the source, circumscribe the fuse etc. the problem carries on the processing, adopt four pins of the PT100, and designed to enlarge to handle the electric circuit reliability. Air pressure signal, at analyzed to spread the mark predestination of the feeling machine according to after, for attaining the resolution of the system to request the accuracy, for alleviate the burden of the main CPU, we designed the specialized electric circuit module at the same time. Adjust circuit was designed to humidity, direction of wind, wind velocity, rainfall signal after carry on the analysis.At the same time, the clock, memory and the interface of GPRS electric circuit was designed.Finally, a few key problems of automatic station software and reliability designs was analyzed. While measuring temperature with the Pt100, carry on computing the temperature according to the formula, the calculation quantity is very huge, through analysis the system request of temperature range and accuracies, the processing calculate way of the temperature did not adopt the formula calculation, use segment straight line to draw up to match it, which can be alleviate the CPU's work and realize the accuracy. The air pressure sensor signal is not linearity, with the curve not the line corrects to compensate with temperature, the high accuracy of the realization air pressure measure.In reliability design of the soft and hardware anti- interference problem and defended the thunder to avoid the thunder problem to carry on analysis and discussion, and definitely put forward the solution measures.