双传声器法吸声系数测量系统设计及误差分析

ccording to the method of two-microphone transfer function method，the paper designed a measurement system about the material normal absorption coefficient based on Technique of virtual instrument and LabVIEW development environment. The system used modular block to realized the signal produced,microphone calibration,data acquisition and sound coefficient calculation function.Under the identical experimental conditions，the measurement results are compared with BSWA TECH material which is confirmed that the system is reliable. Through analysis of the data processing，the frequency resolution and the influence of the sound absorption coefficient of the distance between the microphone was discussed.