Design Of Automatic Data Acquisition System Of Water Situation Based On GSM

Automatic Data Acquisition System(ADAS)for irrigation water condition is an important part of irrigation informatics work. The system mainly holds the function of collecting and processing data of water condition, and giving right information. The choice of the way of transferring the water data is very important to the system.The application of ADAS for irrigation water condition is often in the desolate rural area, so the wireless communication is the best choice, GSM network is developing fast these years, we put forward the idea of using GSM short message to transfer irrigation water data. The composition of ADAS is given in the paper firstly, including Water Level Sensor,A/D Converter,Single Chip Computer,RS232 Interface,Clock Chip Circuit,GSM Module etc. AT instruction and the use of AT instruction sending/receiving short message is also discussed in the paper. Finally the limitation of the short message is analyzed, and the scheme of using GPRS for further improvement is put forward.The run up step of ADAS for irrigation water condition is listed as below, first the system is powered up, the modules are reset, then A/D converter begins sampling the inputsignals while the process is controlled by the clock module. The sampled data is store in Single Chip Computer. We developed AT instructions to control GSM module to send or receive short message. The clock module controls the time when to send short message. The send of the water data is controlled by the Control Center via short message. The identified code of the control center is store in the ADAS at first. If the comparison result is same, ADAS sends the irrigation water data immediately, otherwise, the transferring of data is not started.