Research Of Wireless Sensor Network Used In Vibration Signal Monitoring

Wireless Sensor Networks is self-organizing distributed network which are made of large number of sensor nodes. It is a kind of emerging comprehensive technology with sensor technology, MEMS technology, wireless communication technology and distributed information processing technology. Wireless Sensor Network gets more and more attention due to its advantages such as low cost, easy to install, maintain and convenient update and so on. At present, the study of Wireless Sensor Networks become more in-depth, application fields are more widely.It is better that by using the wireless sensor network collects vibration signal which monitors state of mechanical equipment than traditional cable sensor in the wiring process. It reduces the environment restrictions on sensors, so the application is more convenient. Now, Wireless Sensor Networks' applications for vibration signal is limited to the slowly varying signal collection, but the vibration signals of mechanical equipment are a large number of high frequency and high acceleration signals. At present, the widely used nodes platform can not really meet the requirement, so this paper voluntarily designs the Wireless Sensor Network node platform, and solves direct at the requirement of high frequency vibration signal collection and transmission.This paper introduces the characteristics of system structure and key technologies of Wireless Sensor Network, according to compare and analyse the standards of the several current wireless communication. It introduces hardware design of Wireless Sensor Network node and relevant procedure design detailedly. This design according to the characteristics of vibration signal and try to select the principle of low-power chips, selects ADXL345, MSP430 and CC2420 as the main chips of different models. After carefully read each chip's working principle and related research, I complet the circuit design of each module and circuit board's production. At the same time, through the C programming language, I complete the initialization of each module, the communication interface connection and registers'literacy, this paper complete the software design of the node's platform.It made Wireless Sensor Network realize collection and transmission of data.The nodes of Wireless Sensor Network are numerous, between the data of collection exists correlated, it makes the information redundancy greatly, leads to consuming large amounts of energy to transmission the date. This paper presents a method about distributed wavelet data compression, the traditional wavelet transform is introduced into the Wireless Sensor Network. This method makes for reducing signal noise and improves the quality of gathering information. This paper introduces the approaches which using wavelet compressed distributed storage and searching the date. This method increases the data storage efficiency, and by using the self-similarity features of wavelet coefficient, it can inquire the data which needed rapidly and accurately, and better meet the requirements of reducing the nodes'energy.This thesis complete the overall design of WSN, and verified the feasibility of vibration signal collection by means of the experiment. And it puts forward the algorithm named data compression, which optimized the performance of the node, and achieved the effective energy saving, while improving data transmission reliability.