Research On Flow Remote Monitoring System Based On GPRS Wireless Network

The methods of wire network are mostly adopted in the traditional flow meters, but their transmission distance, expansibility and cost-efficient etc. are limited. With the development of Internet and mobile communication, GPRS has offered a new method to monitor the flow from distance.Therefore, the paper introduces a flow remote monitoring system based on GPRS wireless network, which is the combination of flow measurement technology and remote monitor technology. Meanwhile each part of the system including software and hardware has been analyzed, designed, debugged concretely.The system consists of three parts: data acquisition terminal, monitor center and mobile monitor terminal. Data acquisition terminal uses 8051 microcontroller as the control core for data acquisition and communication. The system firstly collects the differential pressure, absolute pressure and temperature signals through sensors flow accumulation. Then, the analog signals are converted into digital signals through A/D conversion, which are sent to the microcontroller to be disposed and calculated. The data is then sent to monitoring center and mobile monitor terminal by GPRS wireless module. For GPRS packet transmission, the software realization of PPP, IP, TCP, UDP network protocols is necessary. Because of the limitation of storage resource in the microcontroller, design method of the embedded TCP/IP stack is used in the program exploitation. Monitor center is settled in a public network computer with fixed IP address. Visual C++6.0 is used for the realization of software. Then data connection and transmit is realized by the standard interface for network programming Winsock. On this basis such functions are implemented as data display, data query, remote control and data alarm. In this paper, the mobile monitor terminal to monitor field data whenever and wherever is designed.Hardware devices are composed of notebook PC and GPRS data transmit terminal. The acquisition and control of field data is implemented by software. The experiment demonstrates that the system can meet the remote flow monitor's requirements, such as long transmission distance, real-time ability, reliability, extension and low cost of construction and running.