摘要
MEMS热膜式壁面剪应力传感器的输出信号是带有基础电压的微弱电压信号,无法通过放大器直接放大的方法实现高精度测量。文章提出在输出信号放大前增加信号平衡环节,在保留有效信号的前提下减小基础电压,再通过放大的方法实现其高精度测量,有效解决了MEMS热膜式壁面剪应力传感器微弱信号检测的难题。文章介绍了MEMS热膜式壁面剪应力传感器微弱信号检测的技术方案、关键技术、测试检验及试验应用实例。
The weak signal of MEMS hot-film wall shear stress(WSS)sensors is hard to detect by direct amplification due to the inherent basic voltage.An effective method to solve this problem is proposed,which is to add an output-balancing system(OBS)before the signal is amplified.The basic voltage is decreased while the signal is retained.The development of the outputbalancing system is presented,including the technical scheme,key technologies,examination and application.
引文
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