Key Technology Research Of Infrasound Source Positioning Based On Wide-Area Sensor Network

As infrasound has features of low frequency, long wavelength, far transmission capability and low energy attenuation, infrasound source monitoring system based on the wide-area sensor network is becoming a hot research point in recent years. This paper carried out systematic researches on some key technologies related with infrasound source-positioning problems.The key technologies, which are related with infrasound source-positioning problems based on wide-area sensor network, include multi-array and multi-algorithm combination, the high precision and intelligence of the acquisition equipment, diversity of the transmittion, data auto loading to the database and graphical interface display. This paper, aiming at these key technologies, carried out main works as follows:First,the paper discussed the various features influencing positioning, simply introduced several common methods of acoustic source-positioning, and compared their respective features. Considering the problems that time delay estimation can't position multiple objectives and beam forming is easy to form virtual sources, the idea of multi-array and multi-algorithm combination is proposed, which means that using beam forming algorithm to calculate the direction in the sub-array and using the time delay estimation algorithm to calculate the distance in the large array.Then the paper analyzes and simulates the pre-layout sub-array and the result shows that the pre-layout sub-array is capable to position multiple infrasound sources.The paper puts forward the overall design scheme and design principles of the array system. Signal conditioning module, ADC module and communication module are introduced to the array, which has improved the sample precision, the sample rate and the flexibility when setting down.During the software design, workbench is adopted to develop the database, and C++ programming technology under Qt environment, Qt class library and corresponding Qwt expending class library are combined together to achieve the function of data auto loading to the database and graphical display, which makes the interface beautiful, friendly, humanized, and also raises the efficiency of data extraction and display. Finally the finished array system was debugged in the laboratory and set down in the actual environment. The problems that should be noticed in the process of setting down were summarized and corresponding solutions were also proposed.The research results of this article made the layout of the array even better and more according with the actual requirements, which are good references to the layout of other following sub-arrays and also the final large array.