宽带LFM信号数字脉压匹配滤波和去斜率方法的比较-徐成节

LFM¹,,,(,610054):在线性调频(LFM)信号数字脉压中,采用不同的数字脉压处理方法对脉压结果会有不同的影响本文经理论分析和仿真验证,比较了数字脉压匹配滤波和去斜率两种方法的脉压性能在这两种方法中,采样率目标回波信号时延和目标多普勒频率的变化对数字脉压结果都有一定的影响,并且目标回波信号时延和目标多普勒频率之间有一定的对应关系仿真试验结果为在工程应用中选择合适的数字脉压处理方法提供了依据:线性调频(LFM);匹配滤波;去斜率处理:TN957.51+3:A:1672-2337(2004)03-0168-05ComparisonofDigitalPulseCompressionMethodsUsingMatchedFilteringandDechirpProcessingforBroadbandLFMSignalXUCheng-jie,HUANGWei,CHENZhu-ming,XIANGJing-cheng(CollegeofElectronicEngineering,UESTC,Chengdu610054,China)Abstract:TheresultsofpulsecompressionforbroadbandLFMsignalsaredifferentwhenusingdifferentmethods.Thesemethodsincludethematchedfilteringprocessinganddechirpprocessing.Theoryanalysisandsimulationresultsprovedthatpulsecompressionperformancesareinfluencedbysamplingfrequency,Dopplerfrequencyandthesignalde-laytimebetweenthetargetandtheradar.TherearesomerelationsbetweenDopplerfrequencyandthedelaytime.Simu-lationisgiven.Simulationresultscanbeusedtoselectrightdigitalpulsecompressionmethodinpracticalapplications.Keywords:linearfrequencymodulation(LFM);matchedfiltering;dechirpprocessing1,A/DDSP,,,;,,,LFM,,2,,,(),320046RadarScienceandTechnologyVol.2No.3June2004¹:2004-01-0511,FFTS(X),H(X),(IFFT)(1):y(n)=IFFT[S(X)#H(X)]=IFFT{FFT[S(n)]#FFT[h(n)]}(1),S(n)A/D,h(n)1LFM,[2,4]y(t)=A1[PB(t-S1)]PB(t-S1)exp[j2Pf0(t-S1)](2),A1,f0,S1()(2):LFM,1/KT=1/B[1,6],c/2B,c2,,,2S(n)SL(n),FFT:y(L)=FFT[S(n)#SL(n)](3),S(n)SL(n)S2[3]S(L)=sin{PKT[L/KT-mTs2]}sin{PKTs2[L/KT-mTs2]}#exp{jU+j(N-1)PTs2[KmTs2-L/T]}(4),Ts2,S2=mTs2(4):,1/KT=1/B,c/2B[3],B,LFM,B,(1)(3),,IFFT,A/D,,(2)(4),,,,,,33.1Nyquist,,,,LFM(-B/2,B/2),B,(1)[3]fm=-KmTs2,fmmTs2,mTs2nT,2fm,2fm=2KmTs2=BmTs2/TnB,A/DB200MHz,,200MHz;,10MHz16920043徐成节:宽带LFM信号数字脉压匹配滤波和去斜率方法的比较3.2(1)(2),,,(3)(4),,,,(),:-T/2Ts2+m[l[T/2Ts2-m(5)(5),S2=mTs2,m,,,S2=mTs2=0,,,,,,,,,,,,;,,3.3LFM,fd,[2,3,4]S(t)=A#rect(t-ST)exp{j2P[f0(t-S)+12K(t-S)2+fd(t-S)]}=A#rect(t-ST)exp{j2P[f0(t-S)+12K(t2+S2)+(fd-KS)t-fdS]}(6)(6),,S,,t,,,fd,S=fd/K,K=B/T,(1)(3),S(t)(6),Sfd,,fd,K,fd=KS44.1LFM,T=30Ls,B=200MHzfsB/20B/10B,fd=0kHz,,,(RMS)33,3,fsB/20B/10B,(),,B/20,A/D4.2LFM,fs1=2B=400MHz,Ts1=1/fs1=215ns;17023fs2=B/20=10MHz,Ts2=1/fs2=011Ls,fd=0kHz,,(RMS)454545,,,RMS,3dB,,(RMS),S3Ls=T/10,RMS10dB,,,T/10,4.34.2,[0,Ts];,[0,T/10],fd=0kHz,10kHz20kHz,67676,,,fd=10kHz,fd=0kHz016Ts,014Ts;fd=20kHz,fd=0kHz112Ts,012Ts7,,(),,:fd,K(fd=KS)17120043徐成节:宽带LFM信号数字脉压匹配滤波和去斜率方法的比较5,,,,,,,,,,,:[1].[M].:,1984.128-151.[2],.()[M].:,2001.112-151.[3],.[J].,2003,25(3):8-10.[4].[J].,2000,29(3):12-15.:,1975,19997,;,;20029;SAR,1968,19907,;19944,;,;SAR17223