Noise Spectrum Analyzer Built-In DSP Technology

The paper develops Noise Spectrum Analyzer using DSP(Digital SignalProcessing)technology. The Noise Spectrum Analyzer is a measuring instrument whichintegrates the functions of Spectrum Analyzer, Sound Level Meter, Noise StatisticsAnalyzer, Data Acquisition, Digital Recorder and Noise Dosimeters. Its performanceproperties must comply with GB/T17181-1997 and IEC61672-2002 standardrequirements of a sound level meter, and must satisfy IEC651 and GB/T3241Octave-Band and One-Third-Octave Band Filters requirements.The development trendofNoiseSpectrumAnalyzerisminiaturization,digitalandbuilt-inDSPtechnology.Firstly, this paper introduces configuration and principle of a Noise SpectrumAnalyzer in detail. Then, it provides an overview of the general methodology for DSPalgorithms. Next, it is concerned with frequency weighing filter algorithms, timeweighing filter algorithms and one-third-octave band filters algorithms. The NoiseSpectrumAnalyzerpresentedinthispaperiscomposedofasinglechipcomputercalledMSP430F149, a 320*240 LCD displayer, a keyboard, a set of sound sensor and itsinterface circuit, and the other auxiliary circuits. Finally, it gets some conclusions anddirections for future works.The simulation results show that the performance propertiesof the frequency C-weighing filter, frequency A-weighing filter, time fast-weighingfilter, time slow-weighing filter, and one-third-octave band filters comply with relatedstandards requirements.Future work is required to improve high frequency response offrequency C-weighing filter and frequency A-weighing filter, and to improve stabilityandaccuracyofone-third-octavebandfilters.