Design And Implementation Of Water Quality Monitoring System Based On NB-IoT

Promoting green development is an important content of China's 13 th Five-Year Plan and water pollution has always been a prominent environmental problem in China of which quality monitoring technology can play an important role in monitoring and protecting the water environment.At present,water quality monitoring technology is mainly divided into manual sampling detection,wired monitoring and wireless monitoring.And wireless monitoring is a more ideal method for water quality monitoring now.Water quality wireless monitoring technology is divided into short distance monitoring and remote monitoring.The coverage of wireless short distance monitoring technology is limited and can't make a breakthrough in remote monitoring and the traditional wireless remote monitoring technology has such problems as high power consumption,high flow cost,easy to be shielded signal and complex arrangement of nodes.Aiming at the problems existing in traditional wireless water quality monitoring technology and combining with NB-IoT(Narrow Band Internet of Things)technology with the advantages of wide coverage,low power consumption,low cost and simple node layout about,this thesis designed the NB-IoT based water quality monitoring system in the basis of the sensor technology.The system is composed of NB-IoT water quality monitoring hardware terminal,connection management server and upper computer monitoring platform.The NB-IoT water quality monitoring hardware terminal samples the water temperature,PH,turbidity and TDS water quality parameters,and transmits it to the connection management server.The monitoring platform of the upper computer acquires the water quality data connected to the management server and displays it visually.The main work of this thesis is as follows:1)Designed and manufactured the NB-IoT water quality monitoring hardware terminal.The terminal can automatically collect the temperature,PH,turbidity and TDS water quality data,and upload the data to the connection management server by NB-IoT data transmission technology.It has the advantages of miniaturization,low power consumption,long-distance transmission and integration of function expansion and so on.2)Constructed the data transmission program based on the CoAP protocol.The application layer protocol of NB-IoT adopts the CoAP protocol with simple message format and small amount of data which is suitable for resource-constrained devices,so that the power consumption of NB-IoT terminal is reduced.The profile file and codec plug-in are designed,and the data transmission format is defined.Based on this,a data transmission program based on CoAP protocol is constructed.3)Based on MVC design pattern,the PC monitoring platform with data visualization is constructed by Java language and JfreeChart open source package.The position layout mode relative to the mother container is defined by the monitoring platform of the upper computer,which makes the layout of the upper computer more reasonable and the upgrading and maintenance of the upper computer more simple.The data can be visualized in the form of line chart based on JfreeChart open source package.4)Constructed the data local storage file system which based on RC4 encryption algorithm.A local file system is established because of the problem that the traditional monitoring platform can only display real-time data on-line,but can't query and analyze historical data.In order to protect the security of user's local data,RC4 algorithm,which is efficient and non-linear,is used to encrypt the data locally.The system function test is carried out with Huaihe River basin as monitoring point,including the function test of NB-IoT water quality monitoring hardware terminal connecting management server and upper computer monitoring platform.The test results show that the monitoring system can realize the collection and wireless transmission of the Huaihe River temperature,PH,turbidity and TDS data,and the connected management server can receive and parse the data,and the upper computer can obtain,local storage encryption analysis and visual display data.The designed system satisfies the setting function,validates the feasibility of the system design,and provides an effective monitoring scheme for the wireless monitoring of water quality,which has certain application value.Figure [80] table [1] reference [55]...