Ground Vibration Based On Wireless Sensor Network Positioning Key Technology Research

In this paper a system which can locate the targets moving on the ground is designed. The designed system collects the vibration signal excited by persons or vehicles moving on the ground to locate the targets. Hardware solution and software development of this system are completed after researching the theories about seismic waves and wireless sensor networks.In this paper, the propagation and attenuation of seismic waves, filtering techniques based on EMD, and location algorithm based on TDOA are researched firstly. Then an efficient location algorithm for targets moving on the ground is proposed, and an adaptive low-pass filter based on EMD is designed to filter out the noise mixed with the target signal. The proposed location algorithm combines both of Chan and Taylor location algorithm, the result of Chan location algorithm is used as a pre-estimated target location, then Taylor algorithm uses this value to locate the target once again. In this paper TDOA values is divided into many sets, utilizes the proposed algorithm to locate target respectively with each set of TDOA measurements. In order to achieve better performance, locating the target by the method of mining the sum squared deviations of location results which obtained by previous calculation again. MATLAB simulation results show that the proposed location algothim has better location accurary than previous related approaches.In this paper, the experiments of synchronous trigger and crystal test have been completed.the speed and energy propagation model of seismic waves with the distance also have been tested. A signal target locating test has been done to ensure the reliability of our proposed algothim in real environment.