Design Of Wireless Gateway Based On Wsns Oriented Water Environment Monitoring

Since the reform and opening up, the chinese economy has achieved a rapid development, economic aggregates increase dramatically, yet natural resource dries up increasingly, especially the water pollution and water shortage are becoming more serious, it is seriously limiting long-term development of China. Protection of water resources is a long-term policy of China. Water environment monitoring is an important source of information for water resource management and protection. Traditional monitoring methods can not meet modern environmental monitoring and information management requirements. Constructing a networked water environment real-time monitoring system without geographical, climatic and time limits is urgently necessary.This paper designs a gateway device for water environment monitoring system based on wireless sensor network (WSNs) - the wireless gateway. In the design, the wireless gateway uses GPRS to connect the wireless gateway and the remote monitoring center for wireless data communication; uses ZigBee technology which is widely used in the WSNs to organize data monitoring networks; uses CC2430 module as a coordination device for the management of ZigBee network; uses low-power microprocessor MSP430F1611 as main controller of wireless gateway to control and coordinate the entire system; through GPRS Modem and ZigBee module communication to achieve communication between two kinds of heterogeneous network.According to the need for water environment monitoring, this paper analyzes the function requirements of the wireless gateway, presents the water environment monitoring system based on WSNs, focuses on the system's communications hub - the wireless gateway and designs its soft and hardware system. In the hardware design of the wireless gateway, this paper gives the details of the micro-controller circuit, flash memory circuit, real-time clock circuit, CC2430 module, GPRS Modem interface circuit design. In its software design, respectively, this paper gives the details of software design for the dual-processor CC2430 and MSP430. Software design includes ZigBee protocol stack, its application development, MSP430'sμC / OS-II application development, custom communication protocols between CC2430 and MSP430 and the frame protocol design for the whole water environment monitoring system.Finally, this paper describes the system testing. The results shows that: the wireless gateway enables the formation of star and tree ZigBee network, realizes efficient two-way communications of the data and commands in the GPRS networks and ZigBee networks, meets with water environment real-time monitoring system requirements, and has broad application prospects.