Remote Real-time Information Acquisition System For Crop Water Requirement Diagnose

With the growing scarcity of water shortage and decrease of agricultural water becauseof other water consumption, the mode of irrigation of agricultural water needs to convert fromthe extensive irrigation mode to intensive precision irrigation mode with advanced technologyequipment, so that the limited water resources can meet more demand for farmland irrigating.Crop water requirement Diagnosis and irrigation decision-making are premises of precisionirrigation and intelligent management of agricultural water. Accurate, rapid and reliableevaluation of crop water requirement status is based on crop water requirement informationwhich is closely related to real-time monitoring and diagnosis of crop water status. Soresearch on crop water requirement information acquisition system attaches significance toimproving informationizing crop water requirement diagnosis and irrigation decision-making.According to current problems of domestic crop water requirement acquisition system, remotereal-time water requirement acquisition system was researched in the thesis. The mainresearch contents are included as follows:(1) Index system for the Crop water requirement acquisition system was established inthe thesis according to FAO Penman-Monteith formula which is a widely used method ofcalculating crop water requirement in the world and soil factor which affects crop waterrequirement.(2) General scheme, composition and characteristics of the system were detailed in thethesis. MCU(Microprogrammed Control Unit) is based on MSP430F149microcontroller ofTI(Texas Instruments). The whole system includes sensors collecting crop water requirementinformation, multiplexers, S/H(sample/hold), and the A/D(Analog/Digital) converter, datamemory, keyboard, real-time clock, LCD(Liquid Crystal Display), power supply, GPRSmodule and single chip etc. Multi-channel switch, sampling holder and A/D converter areintegrated into MSP430F149microcontroller.(3) The design of hardware of the system is modular and opening. Hardware can becontrolled and configured by software. The hardware of the lower computer of the crop waterrequirement system includes Main function of the system includes sensor module, MCU module, real-time module, LCD module, keyboard module, data storage module, powermodule, GPRS module. The software of the lower computer was developed and debugged byIAR Embedded Workbench, which can achieve data collecting, A/D, digital filtering, datastorage, displaying and transmitting.(4) MFC(Microsoft Foundation Classes) was used to develop the host computerapplication software, operation is simple, and the interface is friendly and beautiful. Hostcomputer can display received data and time of receiving data, then saves the data in textformat to the specified folder.(5) Ultra-low power MCU was adopted in the system. The system can keep long termoperation in battery-powered case as low power design, can achieve timing data acquisition inthe unsupervised case and time of data acquiring can be adjusted according to collectingdemands. Data can be transmitted to a computer wirelessly in real time. Experimental resultsshow that the system has high stability. Upper computer can receive, display and savemulti-channel crop water requirement data well. The system can be applied in irrigationdecision-making system to monitor crop water requirement information in real time.