Design And Implementation Of Wireless Sensor Network Nodes

Sensor networks are integration of sensor techniques, nested computation techniques, distributed computation techniques and wireless communication techniques. They can be used for testing, sensing, collecting and processing information of monitored objects and transferring the processed information to users. Sensor network is a new research area of computer science and technology and has a wide application future. Both academia and industries are very interested in it. The concepts and characteristics of the sensor networks and the data in the networks are introduced, and the issues of the sensor networks and the data management of sensor networks are discussed. The advance of the research on sensor networks and the data management of sensor networks are also presented.A typical wireless sensor network hardware, usually including sensors nodes, the gateway nodes and management nodes.This project introduces a wireless communication platform based on nRF905. It is easy to be extended far new applications, and has smaller cubage and lower cost. The system uses STC12LE5412AD single chip computer as MCU to control receiving, transmitting wireless signals. It links to a wireless sensor network gateway node via RS-232 serial port to transmit data to the central database, and joints to end-user's sensors through RS-232 serial port to collect data.This paper introduces the background and application of wireless sensor networks first, and has a particular description to every module in each section.According to the needs of application, an overall planning on the system was carried out based on analyzed short- range wireless communication; the structures of the wireless node module was also designed. The main devices of the system were chosen carefully on the consideration of low power consumption and high anti-interference performance.Above the analyses, this thesis explains the hardware and software of the design in detail. In terms of hardware, it introduces the MCU module, the wireless module, and the designing and debugging on hardware circuit. In terms of software, it introduces the working flow of the transmitting module and the receiving module.In the end a test on the system was carried out. After the accomplishment of the hardware and software design of the node module, combined with the gateway system, a series of sensor network model are constructed. And based on it, the test of relevant functions and performance figure is finished and the results manifested that the wireless node module designed in this paper have many merits such as a small size, low power consumption, reliable and steady data transmission and high resist interference performance. The system can serve well in wireless data acquisition and other short-range wireless data transmission areas.