相关函数在检测周期性信号中的应用

　ISSN1008-9446CN13-1265/TE　　　JournalofChengdePetroleumCollege91,20073Vo.l9,No.1,Mar.2007杨　墨1,孙　文2,赵志骏3,孙剑波3(1.北华航天工业学院机械工程系河北廊坊065000;2.承德石油高等专科学校电工系河北承德067000;3.承德石油高等专科学校科技处河北承德067000):。。。,,。:相关函数;数字信号处理;白噪声;信号功率:TB53　　:B　　:1008-9446(2007)01-0025-03CorrelationFunction-basedAlgorithmforDetectingPeriodicSignalYANGMo1,SUNWen2,ZHAOZhi-jun3,SUNJian-bo3(1.DepartmentofMechanicalEngineering,NorthChinaInstituteofAerospaceEngineering,Langfang065000,Hebei,China;2.DepartmentofElectricandElectronicEngineering,ChengdePetroleumCollege,Chengde067000,Hebei,China;3.SectionofScienceandTechnology,ChengdePetroleumCollege,Chengde067000,Hebei,China)Abstract:Thedefinitionandphysicalsenseofcorrelationfunctionareintroducedatthebeginningandthensomeimportantqualitiesarefetched.Wedesignthealgorithmtodetectperiodicsignalfromwhitenoisebythederivation.Aftersoftwaresimulation,wefindthatthealgorithmisnotonlyeasytoberealized,butalsoefficienttohelpdetecttheperiodofusefulsignalevenwhenthenoisepowerislargerthanperiodicsignalpower.Keywords:correlationfunction;DSP;whitenoise;signalpower　　　:2007-01-29　　　:　(1980-),,,,:。　　,,。,,[1],。,。。1　数学原理x(n)y(n):rxy(m)=∑∞n=-∞x(n)y(n+m)(1)　　m,n,m,n。ryx(m)m,x(n)y(n)m,,,。y(n)=x(n),DOI牶牨牥牣牨牫牫牱牱牤j牣cnki牣jcpc牣牪牥牥牱牣牥牨牣牥牥牳20079　1　:rxx(m)=∑∞n=-∞x(n)x(n+m)(2)　　y(n)mx(n)。x(n)mx(n+m)。rxx(0)=∑∞n=-∞x(n)x(n)=Ex,rxx(0)x(n)。,rxx(0)。,:rxy(m)=limN→∞12N+1∑Nn=-Nx(n)y(n+m)(3):rxx(m)=limN→∞12N+1∑Nn=-Nx(n)x(n+m)(4)x(n)(),T,x(n),rxx(m)=limN→∞12N+1∑Nn=-Nx(n)x(n+m)=limN→∞12N+1∑Nn=-Nx(n)x[(n+T)+m]=rxx(m+T)　　,,。2　仿真结果及分析x(n)Ts(n)0,1,1,-3db(),1x(n)。。x(n),()。x(n),m,m100,m-rxx(m)2。2rxx(m)。x(n):rxx(m)=limN→∞12N+1∑Nn=-N[s(n)+u(n)][s(n+m)+u(n+m)]=rs(m)+rus(m)+rsu(m)+ru(m)0,m0,rus(m)rsu(m)0。[2-3],ru(m)=AωCe-|mωC|/2。ωC,A。26　　,:,ωCru(m)m0。,rxx(m),m=0,T,2T…,x(n)。3　结论。,,,。,,。:[1]　朱昊.复自相关技术在声学多普勒流速剖面仪中的应用及[J].兵工学报,2006,(5):451-458.[2]　丁凯.混沌信号发生器[J].系统工程与电子技术,2006,(12):1957-1959.[3]　周浩敏.谐振式微小型压力传感器数字闭环系统[J].北京航空航天大学,2006,(11):1312-1316.(上接第16页)5　实例分析(,)(Bopp/pp),2,A1(15,494),A2(45,766),(6)1.11×10-2cm3/(m2Pad),7.02×10-14cm3cm/(cm2sPa),(1.08×10-2cm3/(m2Pad),6.80×10-14cm3cm/(cm2sPa)。:[1]　GB/T1038-2000.[2]　沈祥玖.VB程序设计[M].北京:高等教育出版社,2000.27