小波分析在超声测厚信号特征提取中的应用

20103212,,,,(中北大学电子测试技术国家重点实验室,太原030051):采用超声波对旋压固体火箭发动机的绝热层厚度进行检测时,检测信号中的纹理噪声影响了界面回波的确定,进而影响绝热层厚度的准确测量通过分析绝热层超声测厚信号特点和噪声来源,提出了利用小波变换对检测信号进行处理的方法仿真结果表明,运用小波分析得到的厚度特征有很大的改善,通过试件厚度的计算,验证了测量的有效性和准确性:超声波检测;绝热层;小波变换;特征提取:TN553;TG115.28:A:1000-6656(2010)12-0948-03TheApplicationofWaveletAnalysisinCharacteristicExtractionofUltrasonicSignalLIUXiao-Lei,WANGZhao-Ba,CHENYou-Xing,JINYong,ZHAOXia(NationalKeyLaboratoryofElectronictestTechnologyinNorthUniversityofChina,Taiyuan030051,China)Abstract:Duringtheultrasonicthicknessdetectionfortheheatinsulationlayerofspinning-madesolidrocketmotors,thetexturenoisesintheechosignalsaffectedthedeterminationoftheinterfacereturningwaveandtheaccuracyofthethicknessmeasurement.Byanalyzingthecharacteristicsofultrasonicthicknesssignalsandthesourcesofthenoises,aprocessingschemeusingawaveletanalyzingpost-processingprogramwasproposed.Simulationresultswerepresentedtoverifythevalidityandtheaccuracyofthemeasurement.Keywords:Ultrasonictesting;Insulation;Waveletanalysis;Characteristicextraction,,,,,1([1])(),,,,,,:2009-11-23:(2007011053);:(1984-),,,A0,S0,,,,,[2]11cpA0,S0,948刘晓蕾等:小波分析在超声测厚信号特征提取中的应用20103212,Ai,:sinAi=clcp(1)Ai)));cl)));cp)))A0,S0,Ñ(1),Ñ,,(1),:sinB=c2cp(2)B)));c2)))(1)(2):B=sin-1(c2c1sinAi)(3),B,,,Ñ,Ò,,ÑÒ$tdcp:$t=2dcp2-c22cpc2,:d=12$tcpc2cp2-c22:A=cpc2cp2-c22(4):d=12A$t(5),cpc2,AÑÒ$t,d,Ò,,,,,2,,2,,,,,,2,,2.1()wden,,33,,,44,949刘晓蕾等:小波分析在超声测厚信号特征提取中的应用201032124,,(1),,32.2,A0,S0cp,c2c2=1177.38m/s;1db422822584302db722792594315sym722852593308cp=2974m/sc2,cp(4),A=1282.13m/s(100MHz),,(5),22$t/s/mm/mm/%db43023.02@10-61.942.211.8db73153.15@10-62.002.29.10sym73083.08@10-61.922.212.7,db7,(下转第972页)SGS2010年11月3日中国上海))),SGS()(SGS)A()SGS,,SGS,,,,,,SGS,SGS,,,,SGS,SGS,,,SGS,,SGS2010,2010,,SGS,,,,SGS,,SGS,950201032122.2VC6.0MFC,,,,,,VC,VC6.0RegisteredActivexControlsMSCOMM:m_Botelv.SetCurSel(8);m_Jiou.SetCurSel(2);m_Shuju.SetCurSel(3);m_Stop.SetCurSel(0);intiBotePos=m_Botelv.GetCurSel();intiJiouPos=m_Jiou.GetCurSel();intiShujuPos=m_Shuju.GetCurSel();intiStopPos=m_Stop.GetCurSel();m_ctrlComm.SetRTSEnable(FALSE);m_ctrlComm.SetDTREnable(FALSE);m_ctrlComm.SetSettings(m_Botelv.Get-ItemData(iBotePos),m_Jiou.GetItemData(iJiou-Pos),m_Shuju.GetItemData(iShujuPos),m_Stop.GetItemData(iStopPos));//m_ctrlComm.SetInputMode(1);//1:m_ctrlComm.SetRThreshold(1);//1:1OnCommm_ctrlComm.SetInputLen(0);//0m_ctrlComm.GetInput();//,,,;,,,,443,1s,,,,,,,:[1].[J].,1991,13(5):135-136.[2],,.[J].,1999,21(2):37-39.[3]RothDJ.Eliminatingtheeffectofplatethicknessvar-iationinultrasonicimagesusingasingletransducermethod[J].Proceedings,1996,2944:76-85.(上接第950页)3,,,,,,:[1]56.[M].:,1980:235-241.[2],.[J].,1999,20(1):88-90.972