Research On An Automatic Environmental Noise Monitoring System Based On ARM And DSP

With the development of the economy, people pay more attention to the living environment. Environmental noise monitoring has become an important part of urban management and planning. According to the requirements of real-time monitoring, traditional manual methods show great weaknesses of isolated points and hysteresis. Automatic environmental noise monitoring system can overcome the weaknesses. It provides comprehensive and reliable data so that environmental protection and city planning departments can effectively carry on the work of environmental quality assessment, noise control, and city construction and so on.An automatic environmental noise monitoring system based on ARM and DSP is developed in this thesis. The system is composed of multiple noise monitoring terminals and one remote monitoring center. Noise monitoring terminals collect noise data and store it in the local database after making calculation operations in the time domain and frequency domain. Then, useful data can be transmitted to the remote monitoring center through the Internet. The noise monitoring terminal can be permanently installed in the city streets or carried around on vihecles. It has the practicability and expansibility. The main results of this thesis are as follows:(1) The structure of the automatic environmental noise monitoring system is designed based on ARM and DSP, and the basic functions of noise monitoring are realized. Based on the advantages of the floating-point DSP chip—TMS320F28335, by using the DMA high speed data transfer operations and the floating-point FFT algorithm, high speed data acquisition and calculation of noise data are achieved.(2) Efficient data management and data visualization on the noise monitoring terminal are realized according to a data management method in the embedded system based on the relational database. Using the embedded database—SQLite, the noise monitoring terminals can store and search multidimensional data including the time domain and frequency domain information, GPS data and time information efficiently. And then, the termimals can display the data in the visualization form.(3) The network communication scheme based on XML is designed, and the mutual mapping algorithm between XML and the relational database is researched. Using the XML data exchange technology, noise monitoring terminals communicate with the remote monitoring center through the network protocol in XML format. The wrapping and parsing of the communication packets are realized through the mutual mapping algorithm between XML and the relational database, and the remote control of the noise monitoring terminals from the remote monitoring center is realized.The ARM and DSP based automatic environmental noise monitoring system developed in this thesis can make up for the weaknesses of the existing equipment on terminal management and distributed noise data acquisition. It lays a theoretical foundation for research on automatic environmental noise monitoring, and it can provide technical support for the implementation of the environmental noise monitoring tasks in cities.