A Design Of Water Quality Monitoring System Based On ZigBee

Water pollution has increased in recent years.Production and living brought about a number of wastewater containing harmful factors,which seriously endangered human health.Therefore,the test and control of water quality seems to be quite critical.But the traditional detection method by experience can no longer meet the needs,and sometimes result in a huge loss;chemical detection method not only makes the process complex and non real-time,but also bring about secondary pollution;modern instrument detection method is a new one,which through the relevant sensors,change the physical or chemical quantity of measured object into electrical signals,then amplify and digitalize the signals by high-gain amplifiers,finally input them to the MCU and parameters are measured accurately.For the water quality measurements of lakes and rivers,as buoys are in the water all year round,it appears inappropriate to set up a special communication line;besides,more and miscellaneous test points make the wiring of monitoring system very complex.Thus,according to the basic theory of wireless sensor networks and the actual needs of water quality monitoring system,an on-line water quality monitoring method based on ZigBee technology is proposed.The system can measure a variety of water quality parameters such as water temperature,PH,conductivity conveniently and intuitively.In this paper,the system's overall design scheme is presented and the hardware and software of system is analyzed and designed in detail.The hardware design of this paper is a modular one,thus the system included wireless transmission module and sensor node module.The wireless node used TI's single-chip CC2430 and low-power amplifier CC2591 solution.The sensor node module was used to sample various water quality parameters through corresponding sensors,and then amplify the collected voltage signal or current signal through the signal conditioning circuit.ZigBee protocol was researched and reduced ZigBee protocol stack is modified and planted based on the standards defined by ZigBee Alliance,and applications and related drivers are programmed,the key program flow chart and some source code is given.Experimental results show that two ZigBee modules can realize a reliable data transmission with 300meters through point to point derect communication,which can meet the real-time requirements of water quality monitoring.To realize a ZigBee network,this system used various water quality monitoring terminals to build the measuring network,communicated with PC through a coordinator.Compared with traditional detection methods,the system of water quality can not only reduce labor intensity and improve detection accuracy,but also has real-time monitoring of continuity.This paper represents a useful effort for the water supply,sewage treatment and other needs of the dynamic monitoring of water quality situations.