实验三离散时间信号的频域分析第一部分.doc

Section:LaboratoryExercise3DISCRETE-TIMESIGNALS:FREQUENCY- DISCRETE- putation AcopyofProgramP3_1isgivenbelow: <-file(s)andpaste.>%ProgramP3_1%EvaluationoftheDTFTclf;%ComputethefrequencysamplesoftheDTFTw=-4*pi:8*pi/511:4*pi;num=[21];den=[1-];h=freqz(num,den,w);%PlottheDTFTsubplot(2,1,1)plot(w/pi,real(h));gridtitle('RealpartofH(e^{j\omega})')xlabel('\omega/\pi');ylabel('Amplitude');subplot(2,1,2)plot(w/pi,imag(h));gridtitle('ImaginarypartofH(e^{j\omega})')xlabel('\omega/\pi');ylabel('Amplitude');pausesubplot(2,1,1)plot(w/pi,abs(h));gridtitle('MagnitudeSpectrum|H(e^{j\omega})|')xlabel('\omega/\pi');ylabel('Amplitude');subplot(2,1,2)plot(w/pi,angle(h));gridtitle('PhaseSpectrumarg[H(e^{j\omega})]')xlabel('\omega/\pi');Answers: TheexpressionoftheDTFTbeingevaluatedinProgramP3_1is- mandis-causesM- TheplotsgeneratedbyrunningProgramP3_1areshownbelow: <InsertMATLABfigure(s)(s)andpaste.> TheDTFTisaperiodfunctionofw. Itsperiodis-2pi Thetypesofsymmetriesexhibitedbythefourplotsareasfollows:RealpartofH(e^{j\omega})isevesymmetries;ImaginarypartofH(e^{j\omega})isodesymmetries;MagnitudeSpectrum|H(e^{j\omega})|isevesymmetries;PhaseSpectrumarg[H(e^{j\omega})]isodesymmetries; : <-file(s)andpaste.>%ProgramQ3_3%EvaluationoftheDTFTclf;%ComputethefrequencysamplesoftheDTFTw=0:pi/511:pi;num=[-];den=[-];h=freqz(num,den,w);%PlottheDTFTsubplot(2,1,1)plot(w/pi,real(h));gridtitle('RealpartofH(e^{j\omega})')xlabel('\omega/\pi');ylabel('Amplitude');subplot(2,1,2)plot(w/pi,imag(h));gridtitle('ImaginarypartofH(e^{j\omega})')xlabel('\omega/\pi');ylabel('Amplitude');pausesubplot(2,1,1)plot(w/pi,abs(h));gridtitle('MagnitudeSpectrum|H(e^{j\omega})|')xlabel('\omega/\pi');ylabel('Amplitude');subplot(2,1,2)