The Design Of Water Quality Monitoring System Based On The Internet Of Things

Water quality is one of the key factors that influence the human health and the sustainable development of society.The requirements on management of water environment are becoming higher with the development of society.The automatic monitoring systems currently used in domestic have such disadvantages as insufficient sampling,limited monitoring scope,poor timeliness etc.So an online water monitoring system based on the internet of things(IOT)is presented in this thesis.It consists of the water quality monitoring terminal,gateway and monitoring center.The measured water-area is divided into several sub-areas,and monitoring terminal and gateway set up in sub-networks.The real-time water monitoring with large-scale and all-weather can be realize through the ZigBee and GPRS platform.Moreover,water quality evaluation is realized by the neural network theory.The monitoring terminal implements collecting data of water quality.The hardware platform of monitoring terminal consists of CC2430 controller,data measuring module,power supply module,auxiliary module.The auxiliary module drives pumps to obtain water samples while getting collection command from CC2430.The measuring module acquisits four vital generic parameters(PH,water temperature,electrical conductivity and dissolved oxygen)and send it to CC2430.CC2430 is responsible for ZigBee wireless network management and data storage and transceiver.The software design of the monitoring terminal is implemented based on the Z-Stack protocol,which makes a multi-level task developing according to the characteristic of water quality sensors and the terminals consisting of wireless networking.The water quality gateway consists of S3C2440A ARM controller,GPRS module,ZigBee coordinator.It not only converts the protocol between the internal ZigBee and public IP network,but also is in charge of analyzing or transmitting the data transferred from management software to monitoring subnet and the sub-net self-managing.A management center of water quality is designed in this thesis.It is developed under the framework of Qt platform and realized data access by implementing IOCP module.In addition,the module of water quality evaluation based upon BP neural network is designed and simulated by MATLAB soft.The management center can realize devices' parameter settings and status monitoring,query and statistics of water quality data and water quality evaluation.The online water quality monitoring system is accomplished.The test results show that ZigBee coordinator's networking structure is steadily in range of 80 m and could be restructured in a short time.IOCP module posses high performance.The deviation for the water quality parameters between sensor sampling value and the standard one is small.Water evaluation module built by BP network using Momentum-adaptive learning rate algorithm is reliability.This theise involvinig technologies such as ZigBee,GRPS,sensor technology and artificial neural network etc offers valuable reference for combining IoT with water monitoring technology.