Design And Realization Of Distributed Wireless Monitoring System Based On Radio-Frequency Technology

The flourishing development of electronic technology promoted the progress of rf circuit and fabrication process of low power circuit, meanwhile, the technology of digital communication and digital modulation have been developed rapidly. They make the wireless communication more economical and operation easily. The advancement of the technology of semiconductor, communication and computer promotes the production and rapid development of the wireless sensor network technology. The wireless sensor network technology is a new research field of measurement and control technology. Compared with the traditional monitoring system, it has good real-time performance, excellent mobility, low cost and has very wide application prospect, which raises the high attention of every government and research institution. The wireless sensor network technology has been a research hotspot.The research progress and present situation at home and abroad of data acquisition system and short distance wireless communication technology are summarized and analyzed. The traditional monitoring system had limitations and the present wireless monitoring had singleness. According to the remoteness and dispersion of the monitoring points, the multiplicity of the monitoring objects, a distributed wireless monitoring system based on microprocessor MSP430 and wireless communication chip nRF905 is designed The overall design of the system and software and hardware implementation of each module are given in this dissertation. The functional characteristics and performance requirements of monitoring nodes are deeply analyzed also. Considering the communication requirement of multi-point to point, a miniature wireless communication network is constructed, then the network topology, the media access control protocol, the hide node strategy, the error retransmission mechanism and the wireless data vertical structure. Furthermore, the low power treatment scheme of nodes is designed, the system power dissipation is reduced and the system life cycle is improved. According to the effects of field interference, the working mechanism based on frequency hopping communication is designed, which can resist the external disturbance efficiently. The design and development of PCB board are realized, each module is debugged and the host computer software, which has the function as data displaying and saving, curve depicting, is completed. Finally, the system function testing is given. The distributed wireless monitoring system designed in this dissertation has the advantages such as low power dissipation, good generality and strong anti-interference ability. The system breaks the limitations of regions and can realize high precision monitoring of multiple signal. It has good popularization value application value in design of wireless monitoring system which has small data quantity to communication.