Free Field Reciprocity Calibration of LS2F Microphone in High Frequency
HE LONG-biao1,WANG Bing-xing2,WU Yun3,NIU Feng1,ZHONG Bo1
1.National Institute of Metrology,Beijing 100013,China
2.Beijing University of Chemical Technology,Beijing 100029,China
3.Jiangsu Institute of Metrology,Naijing,Jiangsu 210027,China
Abstract：To meet the requirements for measurement traceability of air borne ultrasound pressure, PULSE analyzer and reciprocity calibration apparatus are used to found the free-field reciprocity calibration system. High frequency free field sensitivity of LS2F microphones and frequency response from 20 kHz to 51 kHz are obtained with time selective technology. The data with and without time selective technology are compared and the influences of standing wave and reflected wave from wall are analyzed .The result shows that standard deviation is reduced by 1.0 dB with this technology above 40 kHz.
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2012, Vol. 33 
