Analysis of microwave-induced thermoacoustic signals and research-development preprocessor
Wei, Y.; Wang, H.; Zhu, X.; Jiao, T.; Yang, G.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 26(3): 471-474
2009
ISSN/ISBN: 1001-5515 PMID: 19634653 Document Number: 632499
According to the results of analyzing the microwave-induced thermoacoustic signals, the amplitude and frequency were estimated and the designing parameters of preprocessor were decided. Based on the parameters, the signals preprocessor was designed with the band pass frequency ranging from 50 KHz to 3MHz, the gain ranging from 55 dB to 105 dB and the output noise being 1.32 V when the input was zero and the gain was 105 dB. The de-noising method of thermoacoustic signals was also discussed. The signals can be picked up by the preprocessor combined with the digital multipoint average method. The amplitude of signals is only 5 microV or even less. The results indicated that the preprocessor can meet the needs of thermoacoustic signals acquisition in bandwidth, gain and noise control.