卷積碼-代碼資料

functiontransmittedSigal=BPSKmodu(bits,datarate)%0、1序列調(diào)制到載波序列3fc=datarate*2;fs=fc*8;transmittedSigal=[];t=linspace(0.2,2,16);%一個bit16個點carrier=cos(2*pi*t);%兩個載波周期bits=bits*2-1;%單極性馬變雙極性碼fori=1:length(bits)%開始調(diào)制transmittedSigal=[transmittedSigal,bits(i)*carrier];endfunctioncs=channel(modusignal,SNR)%4調(diào)制后的信號、信噪比cs=awgn(modusignal,SNR,0);%加噪functionb=conv(a)%3卷積碼的編碼l=length(a);g0(1,1)=1;%編碼過程的生成序列g(shù)1(1,1)=0;g2(1,1)=0;g0(1,2)=1;g1(1,2)=1;g2(1,2)=1;m0=0;m1=0;m2=0;fori=1:lm2=m1;m1=m0;m0=a(i);c(i,1)=g0(1,1)*m0;c(i,2)=rem((g0(1,2)*m0+g1(1,2)*m1+g2(1,2)*m2),2);endb=[];[mn]=size(c);fori=1:mb=[b,c(i,:)];endfunctiondecode=conv_decode(SS1,SS2,SS3,SS4,NEXT,B,d)%6卷積碼譯碼l=length(d);ifrem(l,10)==0D=reshape(d,10,l/10);D=D';elsed=[d,zeros(1,(fix(l/10)+1)*10-l)];D=reshape(d,10,length(d)/10);D=D';enddecode=[];[mn]=size(D);NE=0;fori=1:mswitchNEcase0forj=1:32error(j,:)=mod((D(i,:)+SS1(j,:)),2);SUM(j)=sum(error(j,:));end[n,k]=min(SUM);decode=[decode,B(k,:)];t=NE+1;NE=NEXT(t,k);case1forj=1:32error(j,:)=mod((D(i,:)+SS2(j,:)),2);SUM(j)=sum(error(j,:));end[n,k]=min(SUM);decode=[decode,B(k,:)];t=NE+1;NE=NEXT(t,k);case2forj=1:32error(j,:)=mod((D(i,:)+SS3(j,:)),2);SUM(j)=sum(error(j,:));end[n,k]=min(SUM);decode=[decode,B(k,:)];t=NE+1;NE=NEXT(t,k);case3forj=1:32error(j,:)=mod((D(i,:)+SS4(j,:)),2);SUM(j)=sum(error(j,:));plot(cc,transmittedsignal(sff));TITLE('BPSK調(diào)制后波形');%------------------------解調(diào)后波形-------------------------figure,sff=1:320;subplot(3,1,1)cc=sff/16;plot(cc,de(sff));TITLE('解調(diào)后波形');%-----------------------抽樣判決結(jié)果------------------------subplot(3,1,2);t=(1/160):(1/160):20;plot(t,designal(ceil(t)));TITLE('抽樣判決結(jié)果');%-----------------------譯碼結(jié)果----------------------------subplot(3,1,3);t=(1/160):(1/160):10;plot(t,decode(ceil(t)));TITLE('譯碼結(jié)果');%5解調(diào)。濾波、抽樣判決function[de,designal]=des(cs)loadLowpass;p=length(cs);l=(length(Lowpass)-1)/2;a=[cs,zeros(1,l)];b=filter(Lowpass,1,a);demode=[zeros(1,l),ones(1,p)];c=demode.*b;c=(c>0|c<0);b=b(c);%濾波，實踐延遲designal=[];de=[];t=linspace(0.2,2,16);carrier=cos(2*pi*t);fori=1:16:length(cs)-15de=[de,b(i:i+15).*carrier];end%解調(diào)l=length(de);fori=1:16:l-15sum1=sum(de(i:i+15))/16;ifsum1>=0designal(ce