Design And Implementation Of Data Acquisition And Control System Based On Wireless Mesh Network

With the development of wireless network technology, wireless Mesh network has been paid more and more attention.,has become one of the key research contents and the development direction of future wireless network technology. The traditional wireless LAN(WLAN) coverage can only form the local network, deployment and installation is more complex, resulting in high costs, while the existence of blind spots in the network and robust.The wireless mesh network uses multi hop network to transmit data, and nodes can self organization, self maintenance in the network, it has the features of wide coverage, rapid deployment and installation, large capacity, flexible structure, low cost and high bandwidth. Therefore, the wireless Mesh network as the key research direction of the network technology.In this paper, the data acquisition and control system based on wireless Mesh network is designed with embedded technology and wireless network technology. The system can collect the data information and control the status of agricultural field, and select the wireless Mesh network as the network transmission medium. The system is divided into two parts, the data acquisition and control terminal and the main control network module,the SPI bus technology is used to communicate with each part. The analog signal acquisition module, digital signal acquisition module and digital signal output module of the data acquisition and control terminal are designed by multi channel acquisition and control interface design,in order to avoid introducing agricultural field interference signal failure circuit system, each module use optocoupler isolation technology for electrical isolation. At the same time, the main control network module in the Linux operating system, in which the SPI driver, USB driver and AODV routing protocol, to achieve the wireless Mesh network. After testing, the accuracy of the analog input module is 5%, the accuracy rate of the digital signal acquisition module and the digital signal output module is more than 98%,, the transmission rate of the wireless Mesh network is reduced and the delay is increased, but the bit error rate is decreased and the robustness is enhanced.This paper combines the wireless mesh network technology and embedded software and hardware technology, and overcomes the disadvantages of the traditional WLAN network at the same time. The realization of a complete data acquisition and control system will have a huge role in promoting the development of industrial acquisition and control system.