数字信号处理基础实验报告一概要.docx
《数字信号处理基础实验报告一概要.docx》由会员分享，可在线阅读，更多相关《数字信号处理基础实验报告一概要.docx（16页珍藏版）》请在冰豆网上搜索。
数字信号处理基础实验报告一概要
LaboratoryExercise1（2classhours）
DISCRETE-TIMESIGNALS:
TIME-DOMAINREPRESENTATION
Project1.1Unitimpulseandunitstepsequences
AcopyofProgramP1_1isgivenbelow.
%ProgramP1_1
%GenerationofaUnitimpulseSequence
clf;
%Generateavectorfrom-10to20
n=-10:
20;
%Generatetheunitimpulsesequence
delta=[zeros（1,10）1zeros（1,20）];
%Plottheunitimpulsesequence
stem（n,delta）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'UnitImpulseSequence'）;
axis（[-102001.2]）;
Answers:
Q1.1Theunitimpulsesequenceδ[n]generatedbyrunningProgramP1_1isshownbelow:
Q1.2ThemodifiedProgramP1_1togenerateadelayedunitsamplesequenceδd[n]withadelayof11samplesisgivenbelowalongwiththesequencegeneratedbyrunningthisprogram.
%ProgramQ1.2
%GenerationofaUnitimpulseSequencewithadelayof11samples
clf;
n=-10:
20;
delta=[zeros（1,21）1zeros（1,9）];
stem（n,delta）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'UnitImpulseSequencewithadelayof11samples'）;
axis（[-102001.2]）;
Q1.3ThemodifiedProgramP1_1togenerateaunitstepsequenceu[n]isgivenbelowalongwiththesequencegeneratedbyrunningthisprogram.
%ProgramQ1.3
%Generationofaunitstepsequence
clf;
n=-10:
20;
delta=[zeros（1,10）,ones（1,21）];
stem（n,delta）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'UnitStepSequence'）;
axis（[-102001.2]）;
Q1.4ThemodifiedProgramP1_1togenerateaunitstepsequenceud[n]withanadvanceof7samplesisgivenbelowalongwiththesequencegeneratedbyrunningthisprogram.
%ProgramQ1.4
%Generationofaunitstepsequencewithanadvanceof7samples
clf;
n=-10:
20;
delta=[zeros（1,17）,ones（1,14）];
stem（n,delta）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'UnitStepSequencewithanadvanceof7samples'）;
axis（[-102001.2]）;
Project1.2Exponentialsignals
AcopyofProgramsP1_2andP1_3aregivenbelow.
%ProgramP1_2
%Generationofacomplexexponentialsequence
clf;
c=-（1/12）+（pi/6）*i;
K=2;
n=0:
40;
x=K*exp（c*n）;
subplot（2,1,1）;
stem（n,real（x））;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'Realpart'）;
subplot（2,1,2）;
stem（n,imag（x））;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'Imaginarypart'）;
%ProgramP1_3
%Generationofarealexponentialsequence
clf;
n=0:
35;a=1.2;K=0.2;
x=K*a.^n;
stem（n,x）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
Answers:
Q1.5Thecomplex-valuedexponentialsequencegeneratedbyrunningProgramP1_2isshownbelow:
Q1.6Thepurposeoftheoperatorrealis:
Complexrealpart.确定一个复数或矩阵的实部；
Thepurposeoftheoperatorimagis:
Compleximagepart.确定一个复数或矩阵的虚部.
Q1.7Thepurposeofthecommandsubplotis:
Createaxesintiledpositions.（将图形窗口分成多个矩形窗格来显示多个图形）
Q1.8Thereal-valuedexponentialsequencegeneratedbyrunningProgramP1_3isshownbelow:
Q1.9Thedifferencebetweenthearithmeticoperators^and.^is:
^数值乘方，而.^矩阵乘方。
Q1.10Thelengthofthissequenceis36.
ItiscontrolledbythefollowingMATLABcommandline:
n=0:
35.
Q1.11Theenergiesofthereal-valuedexponentialsequencesx[n]generatedinQ1.8computedusingthecommandsumare:
sum（abs（x）.*abs（x））;
Theenergyofasequencex[n]isdefinedas
Project1.3Sinusoidalsequences
AcopyofProgramP1_4isgivenbelow.
%ProgramP1_4
%Generationofasinusoidalsequence
n=0:
40;
f=0.1;
phase=0;
A=1.5;
arg=2*pi*f*n-phase;
x=A*cos（arg）;
clf;%Clearoldgraph
stem（n,x）;%Plotthegeneratedsequence
axis（[040-22]）;
grid;
title（'SinusoidalSequence'）;
xlabel（'Timeindexn'）;
ylabel（'Amplitude'）;
axis;
Answers:
Q1.12ThesinusoidalsequencegeneratedbyrunningProgramP1_4isdisplayedbelow.
Q1.13Theaveragepowerofthegeneratedsinusoidalsequenceis:
P=sum（abs（x）.*abs（x））/length（n）;
Theaveragepowerofperiodicalsignal
isdefinedas
，whereNistheperiodof
.
Q1.14Thepurposeofaxiscommandis:
Controlaxisscalingandappearance.（手工设置图中坐标尺度）
Thepurposeofgridcommandis:
Gridlines.（在当前图形上增加或减少网络线）
Q1.15Thesinusoidalsequenceoflength50,frequency0.08,amplitude2.5,andphaseshiftof90degreesgeneratedbymodifyingProgramP1_4isdisplayedbelow.
Q1.16ByreplacingthestemcommandinProgramP1_4withtheplotcommand,theplotobtainedisasshownbelow:
Q1.17ByreplacingthestemcommandinProgramP1_4withthestairscommandtheplotobtainedisasshownbelow:
Project1.4SamplingofaSinusoidalSignal
AcopyofProgramP1_5isgivenbelow:
Answers:
Q1.18Theplotsofthecontinuous-timesignalanditssampledversiongeneratedbyrunningProgramP1_5areshownbelow:
Q1.19Theplotsofthecontinuous-timesinusoidalsignaloffrequency3HzanditssampledversiongeneratedbyrunningamodifiedProgramP1_5areshownbelow:
Theplotsofthecontinuous-timesinusoidalsignaloffrequency7HzanditssampledversiongeneratedbyrunningamodifiedProgramP1_5areshownbelow:
Basedontheseresultswemakethefollowingobservations
Project1.5Drawthefollowingsignals
Q1.20
clc;clear;closeall;
clf;
n=-10:
20;
delta1=[zeros（1,10）,ones（1,21）];
delta2=[ones（1,18）,zeros（1,13）];
delta=delta1.*delta2;
stem（n,delta）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'x[n]=u[n]u[7-n]'）;
axis（[-102001.2]）;
Q1.21
clc;clear;closeall;
clf;
n=-10:
20;
delta=[zeros（1,10）,ones（1,21）];
x=0.5*exp（-0.3*n）.*sin（n*pi/4）.*delta;
stem（n,x）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'x[n]=0.5exp（-0.3n）sin（n*pi/4）u[n]'）;
Q1.22
clc;clear;closeall;
clf;
n=-10:
20;
delta=[zeros（1,10）,ones（1,21）];
x=3*sin（n*pi/5-2*pi/9）.*delta;
stem（n,x）;
xlabel（'Timeindexn'）;ylabel（'Amplitude'）;
title（'x[n]=3*sin（n*pi/5-2*pi/9）u[n]'）;
%axis（[-10200.41.2]）;
升级会员 