自适应抗混叠滤波器在机械振动信号采集中的应用

20042311·64·10008829200411006402自适应抗混叠滤波器在机械振动信号采集中的应用DesignforTrackingFilteringCircuitinAnti-AliasingFilteringofMachineVibrationSignal1000298CPLD10TH76BAbstractAtrackingfilteringcircuitissuccessfullydevelopedbyusinga8th-orderswitched-capacitorfilteranddividing-frequencycircuitbasedonCPLD.Thiscircuitsolvestheproblemofanti-aliasingfilteringwhentherotationalspeedofamachineisnotconstant.Atthesametime,trackingdecadeofeffectivesignals’centerfrequenciesandfilteringotherunnecessarysignalsarerealized.Keywords:keyphasesignal;anti-aliasingfiltering;divi-ding-frequency.101174HC7046MAX291CPLD20040216197222.1274HC70461000MAX29182.22.2.11µFMAX9037414CLK2.2.2NN74HC7046CPLD1000100074HC7046CD4046CPLD1000LIBRARYIEEE;USEIEEE.STD_LOGIC_1164.ALL;ENTITYFQ_DIVIDER1000ISPORT(RESET:INSTD_LOGIC;CLK1000:INSTD_LOGIC;CLK_1000:OUTSTD_LOGIC);ENDFQ_DIVIDER1000;ARCHITECTUREARTOFFQ_DIVIDER1000ISBEGINPROCESS(CLK1000)ISVARIABLECNT1:INTEGERRANGE0TO1000;BEGINIFCLK1000='1'ANDCLK1000'EVENTTHENIFRESET='1'THENIFCNT1500THENCLK_1000='1';CNT1:=CNT1+1;ELSIFCNT1999THENCLK_1000='0';CNT1:=CNT1+1;ELSECNT1:=0;ENDIF;1·65·ELSECNT1:=0;ENDIF;ENDIF;ENDPROCESS;ENDARCHITECTUREART;3CLK1000CLK_1000CPLD161F4500CLK_1000500CLK1000CLK_10001000CLK1000CLK1000CLK1000CLK10002.2.38SCF8MAX291(MAX291)274HC74046clk1000MAX291CLKMAX2911:100:=fcfclk,1010clkACCEACCERA/DA/DCPLD3CPLD[1],,,.[M].,1994.[2].VHDL[M].2002.[3],,.[M].:,1992.[4]JamesRArmstrong,F.CailGray.VHDL[M].:,2002.1000231000M-systems3.52.5FFD128MB90.1GBDiskOnChipDOCDiskOnModuleDOMCompactFlashCardCFPCMCIACard(PC)70305100080010-8287225162659642600717115180400755-8386701883867718028-8555695185533246Flash