2ASK2FSK2PSK数字调制系统Matlab实现性能分析

(圆满word版)2ASK、2FSK、2PSK数字调制系统Matlab实现及性能分析(圆满word版)2ASK、2FSK、2PSK数字调制系统Matlab实现及性能分析(圆满word版)2ASK、2FSK、2PSK数字调制系统Matlab实现及性能分析2ASK、2FSK、2PSK数字调制系统的Matlab实现及性能分析比较前言：数字信号有两种传输方式，分别是基带传输方式和调制传输方式，即带通，在实质应用中，因基带信号含有大批低频重量不利于传达，因此必然经过载波和调制形成带通讯号，经过数字基带信号对载波某些参量进行控制，使之随机带信号的变化而变化，这这一过程即为数字调制。数字调制为信号长距离高效传输供给保障，现已宽泛应用于生活和生产中。其他依据控制载波参量方式的不一样样，数字调制主要有调幅〔ASK〕，调频(FSK)，调相(PSK)三种根本形式。本次课题针关于二进制的2ASK、2FSK、2PSK进行讨论，应用Matlab矩阵实验室进行仿真，分析和改正，经过仿真系统生成一个人机交互界面，以利于仿真系统的操作。经过对系统的仿真，更为直观的认识数字调制系统的性能及影响其性能的各样要素，以便于比较，讨论和改进。重点词：数字，载波，调制，2ASK，2FSK，2PSK，Matlab，仿真，性能，比较，分析正文：一.数字调制与解调原理1.12ASK1〕2ASK2ASK就是把频次、相位作为常量，而把振幅作为变量，信息比特是经过载波的幅度来传达的。因为调制信号只有0或1两个电平，相乘的结果相当于将载频或许关断，或许接通，它的实质意义是当调制的数字信号"1时，传输载波；当调制的数字信号为"0"时，不传输载波。表达式为：Acosct,当ak1s2ASK(t)0，当ak01.22FSK2FSK能够看做是2个不一样样频次的2ASK的叠加，其调制与解调方法与2ASK差不多，主要频次F1和F2，不一样样的组合产生所要求的2FSK调制信号。公式以下：Acos1t,当a1s2FSK(t)k2t，当ak0Acos1.32PSK2PSK以载波的相位变化为基准，载波的相位随数字基带序列信号的1或许0而改变，平常用已经调制完的载波的0或许π表示数据1或许0，每种相位与之一一对应。二．数字调制技术的仿真切现本课程设计需要借助MATLAB的M文件编程功能，对进行调制与解调的设计，并绘制出调制与解调后的波形，误码率的状况分析，软件仿真可在已有平台上实现。1.2ASK代码主函数closeallclearalln=16;fc=1000000;bitRate=1000000;N=50;%noise=ti;noise=10;signal=source(n,N);%生成二进制代码transmittedSignal=askModu(signal,bitRate,fc,N);%调制后信号signal1=gussian(transmittedSignal,noise);%加噪声configueSignal=demoASK(signal1,bitRate,fc,n,N);source代码functionsendSignal=source(n,N)sendSignal=randint(1,n)bit=[];fori=1:length(sendSignal)ifsendSignal(i)==0bit1=zeros(1,N);elsebit1=ones(1,N);endbit=[bit,bit1];endfigure(1)plot(1:length(bit),bit),title('transmittingofbinary'),gridon;axis([0,N*length(sendSignal),-2,2]);endaskModu代码functiontransmittedSignal=askModu(signal,bitRate,fc,N)%signal为输入信号，bitrate为bit速率，fc调制信号频次，N%signal=[00101101];bitRate=1000000;fc=1000000;N=32;t=linspace(0,1/bitRate,N);c=sin(2*pi*t*fc);transmittedSignal=[];fori=1:length(signal)transmittedSignal=[transmittedSignal,signal(i)*c];endfigure(2)%画调制图plot(1:length(transmittedSignal),transmittedSignal);title('ModulationofASK');gridon;figure(3)%画频谱实部m=0:length(transmittedSignal)-1;F=fft(transmittedSignal);plot(m,abs(real(F))),title('ASK_frequency-domainanalysisreal');gridon;%figure(4)画频谱虚部%plot(m,imag(F));title('ASK_frequency-domainanalysisimag');%gridon;endCheckRatePe代码functionPeWrong=CheckRatePe(signal1,signal2,s)rights=0;wrongs=0;forki=1:s-2if(signal1(ki)==signal2(ki))rights=rights+1;elsewrongs=wrongs+1;endendPeWrong=wrongs/(wrongs+rights);enddemoASK代码functionbitstream=demoASK(receivedSignal,bitRate,fc,n,N)loadnumsignal1=receivedSignal;signal2=abs(signal1);%??á÷signal3=filter(num1,1,signal2);%LPF,°ü???ì2¨IN=fix(length(num1)/2);%?ó3ùê±??bitstream=[];LL=fc/bitRate*N;i=IN+LL/2;while(i<=length(signal3))%?D??bitstream=[bitstream,signal3(i)>=0.5];i=i+LL;endfigure(6)subplot(3,1,1);%接收波形plot(1:length(signal1),signal1);title(terminal(includingnoise)');gridsubplot(3,1,2);%接收整流后波形plot(1:length(signal2),signal2);title(

on;

'Waveofreceiving'Waveofcommutate'

);grid

on;subplot(3,1,3);%包络检波波形plot(1:length(signal3),signal3);title(

'WaveofLPF'

);grid

on;bit=[];for

i=1:length(bitstream)if

bitstream(i)==0bit1=zeros(1,N);elsebit1=ones(1,N);endbit=[bit,bit1];endfigure(7)%解调后的二进制波形plot(bit),title('binaryofreceivingterminal'),gridon;axis([0,N*length(bitstream),-2.5,2.5]);endgussian代码%加高斯白噪声functionsignal=gussian(transmittedSignal,noise)signal=sqrt(2)*transmittedSignal;signal=awgn(signal,noise);figure(5)plot(1:length(signal),signal);title('Waveincludingnoise'),gridon;endfsk主函数代码closeallclearalln=16;%二进制代码长度f1=18000000;%

频次1f2=6000000;%

频次2bitRate=1000000;%bit速率N=50;%码元宽度%noise=ti;noise=10;%家性噪声大小signal=source(n,N);%产生二进制代码transmittedSignal=fskModu(signal,bitRate,f1,f2,N);%调制signal1=gussian(transmittedSignal,noise);%加噪声configueSignal=demoFSK(signal1,bitRate,f1,f2,N);%解调source代码%二进制信号产生函数functionsendSignal=source(n,N)sendSignal=randint(1,n)bit=[];fori=1:length(sendSignal)ifsendSignal(i)==0bit1=zeros(1,N);elsebit1=ones(1,N);endbit=[bit,bit1];endfigure(1)plot(bit),title('transmittingofbinary'),gridon;axis([0,N*length(sendSignal),-2.5,2.5]);endfskModu代码%频次调制函数functiontransmittedSignal=fskModu(signal,bitRate,f1,f2,N)t=linspace(0,1/bitRate,N);c1=sin(2*pi*t*f1);%c2=sin(2*pi*t*f2);%

调制信号调制信号

12transmittedSignal=[];for

i=1:length(signal)%

调制ifsignal(i)==1transmittedSignal=[transmittedSignal,c1];elsetransmittedSignal=[transmittedSignal,c2];endendfigure(2)%

画调制后波形图plot(1:length(transmittedSignal),transmittedSignal);title(ofFSK');gridon;figure(3)%画调制后频谱图m=0:length(transmittedSignal)-1;F=fft(transmittedSignal);plot(m,abs(real(F))),title('ASK_frequency-domainanalysisreal'gridon;end

'Modulation);demoFSK代码functionbitstream=demoFSK(receivedSignal,bitRate,f1,f2,N)load

numsignal1=receivedSignal;signal2=filter(gaotong,1,signal1);

%经过HPF，获得高通重量signal3=abs(signal2);

%整流signal3=filter(lowpass,1,signal3);

%经过低通，形成包络bitstream=[];IN1=fix(length(lowpass)/2)+fix(length(gaotong)/2);%延缓时间bitstream1=[];LL=N;i=IN1+LL/2;while(i<=length(signal3))bitstream1=[bitstream1,signal3(i)>=0.5];i=i+LL;endbitstream1figure(5)subplot(3,1,1);plot(1:length(signal1),signal1);title(terminal(includingnoise)');gridsubplot(3,1,2);plot(1:length(signal2),signal2);title(subplot(3,1,3);plot(1:length(signal3),signal3);title(

%每个bit%裁决on;

的抽样点数'Waveofreceiving'AfterPassing'AfterPassing

HPF');gridLPF');grid

on;on;signal4=filter(daitong,1,signal1);signal5=abs(signal4);%整流signal5=filter(lowpass,1,signal5);IN2=fix(length(lowpass)/2)+fix(length(daitong)/2);bitstream2=[];LL=N;%每个biti=IN2+LL/2;while(i<=length(signal5))%裁决bitstream2=[bitstream2,signal5(i)>=0.5];i=i+LL;endbitstream2figure(6)subplot(3,1,1);plot(1:length(signal1),signal1);title(terminal(includingnoise)');gridon;subplot(3,1,2);plot(1:length(signal4),signal4);title(subplot(3,1,3);plot(1:length(signal5),signal5);title(

%经过BPF获得低频重量%经过LPF，形成包络的的抽样点数'Waveofreceiving'AfterPassing'AfterPassing

%延缓时间BPF');gridon;LPF');gridon;fori=1:min(length(bitstream1),length(bitstream2))%裁决if(bitstream1(i)>bitstream2(i))bitstream(i)=1;elsebitstream(i)=0;endendbitstreambit=[];

%接收端波形for

i=1:length(bitstream)if

bitstream(i)==0bit1=zeros(1,N);elsebit1=ones(1,N);endbit=[bit,bit1];endfigure(7)plot(bit),title(

'binaryofreceivingterminal'

),grid

on;axis([0,N*length(bitstream),-2.5,2.5]);endCheckRatePe代码functionPeWrong=CheckRatePe(signal1,signal2,s)rights=0;wrongs=0;forki=1:s-2if(signal1(ki)==signal2(ki))rights=rights+1;elsewrongs=wrongs+1;endendPeWrong=wrongs/(wrongs+rights);endgussian代码functionsignal=gussian(transmittedSignal,noise)signal=sqrt(2)*transmittedSignal;signal=awgn(signal,noise);figure(4)plot(1:length(signal),signal),title('AddingNoise');gridon;end2psk主函数代码closeallclearalln=16;%二进制码长fc=1000000;%载波频次bitRate=1000000;信息频次N=50;%码宽noise=10;%信道加性噪声大小signal=source(n,N);生成二进制代码transmittedSignal=bpskModu(signal,bitRate,fc,N);对信号进行调制并进行频谱分析signal1=gussian(transmittedSignal,noise)%加信道噪声configueSignal=demoBPSK(signal1,bitRate,fc,n,N);%信号解调source代码functionsendSignal=source(n,N)sendSignal=randint(1,n)bit=[];fori=1:length(sendSignal)ifsendSignal(i)==0bit1=zeros(1,N);elsebit1=ones(1,N);endbit=[bit,bit1];endfigure(1)plot(bit),title('transmittingofbinary'),gridon;axis([0,N*length(sendSignal),-2.5,2.5]);endbpskModu代码functiontransmittedSignal=bpskModu(signal,bitRate,fc,N)t=linspace(0,1/bitRate,N);c1=sin(2*pi*t*fc);c2=sin(2*pi*t*fc+pi);transmittedSignal=[];fori=1:length(signal)ifsignal(i)==1transmittedSignal=[transmittedSignal,c1];elsetransmittedSignal=[transmittedSignal,c2];endendfigure(2)%画调制图plot(1:length(transmittedSignal),transmittedSignal);title(ofBPSK');gridon;figure(3)%画频谱图m=0:length(transmittedSignal)-1;F=fft(transmittedSignal);plot(m,abs(real(F))),title('BPSK_frequency-domainanalysisreal'gridon;end

'Modulation);CheckRatePe代码functionPeWrong=CheckRatePe(signal1,signal2,s)rights=0;wrongs=0;forki=1:s-2if(signal1(ki)==signal2(ki))rights=rights+1;elsewrongs=wrongs+1;endendPeWrong=wrongs/(wrongs+rights);enddemoBPSK代码functionbitstream=demoBPSK(receivedSignal,bitRate,fc,n,N)loadnum%读取num储蓄的低通滤波用的数据signal1=receivedSignal;t=linspace(0,1/bitRate,N);c=sin(2*pi*t*fc);signal=[];fori=1:nsignal=[signal,c];endsignal2=signal1.*signal;%乘同频同相sinsignal3=filter(num1,1,signal2);

%LPF,

包络检波

3IN=fix(length(num1)/2);

%?延缓时间bitstream=[];LL=fc/bitRate*N;i=IN+LL/2;while(i<=length(signal3))

%裁决bitstream=[bitstream,signal3(i)>=0];i=i+LL;endfigure(5)subplot(3,1,1);%画接收的包括噪声的波形plot(1:length(signal1),signal1);title(terminal(includingnoise)');gridon;subplot(3,1,2);%相关解调波形plot(1:length(signal2),signal2);title(Fuction');gridon;subplot(3,1,3);%包络检波波形plot(1:length(signal3),signal3);title(

'Waveofreceiving'AfterMultiplingsin'WaveofLPF'

);grid

on;bit=[];fori=1:length(bitstream)ifbitstream(i)==0bit1=zeros(1,N);elsebit1=ones(1,N);endbit=[bit,bit1];endfigure(6)

二进制接收信号波形plot(bit);title(

'binaryofreceivingterminal'

);grid

on;axis([0,N*length(bitstream),-2.5,2.5]);endgussian代码functionsignal=gussian(transmittedSignal,noise)signal=sqrt(2)*transmittedSignal;signal=awgn(signal,noise);figure(4)plot(1:length(signal),signal),gridon;title('Addingnoise')end三种调制方式的性能比较:loadPeRate;loadPeRatep;%赔偿偏差fpeask(15)=1e-3;fpe