基于虚拟仪器技术的声压测量与信号处理

Sound Pressure Measurement and Signal Processing Based on Visual Instrument

汽车风门执行器运转时的声音将直接影响乘车舒适性,文章作为判别风门执行器是否合格的先行研究,实现了基于虚拟仪器的声压级测量。选用预极化电容式自由场声传感器,以NI 9234声音与振动输入模块实现声压信号的动态采集。直接将传感器信号转化成声压会出现负值,经研究后采用LabVIEW编程实现了等效连续声压级和时间计权声压级的转化,并进行了自然环境和连续敲击时的声压测量试验。

The running sound of the air damper actuator affects the ride comfort directly.This paper is the first step to judge the air damper actuator whether pass or not automatically.Pre-polarization capacitance free field microphone was chosen,and the Sound and vibration input module NI 9234 was selected to acquire the sound dynamically.It was found that there was negative value of the sound pressure if the microphone signal was converted without any dispose.Then LabVIEW programming realized the convert of equivalent continuous SPL and time weighting SPL.Finally,the equivalent continuous SPL and time weighting SPL of the natural environment and knock on the desk were measured.