www.gusucode.com > ZBLAST算法仿真源码程序 > ZBLAST算法仿真源码程序/131014135Pro/vblastpic16.m
%tx=4,rx=4 ML QPSK========================================================= %初始化==================================================================== tx=4;rx=4;L=500; SNR=[0:2:10]; % 信源A A=randint(2*tx*L,1); % 经过QPSK调制的V-Blast发射矩阵X % | a=0 a=1 % 未调制比特ab,QPSK调制星座图选取: sqrt(1/2)*|b=0 1+i -1+i % |b=1 1-i -1-i X=zeros(tx,L); AI=A(1:2:end); AQ=A(2:2:end); for k=1:tx X(k,:)=sqrt(.5)*((-1).^(AI(k:tx:end)+1)+i*((-1).^(AQ(k:tx:end)+1))); end % Table table=[1;1;-1;-1]+i*[1;-1;1;-1]; % 慢衰落Rayleigh信道H H=sqrt(1/2)*(randn(rx,tx,L)+i*randn(rx,tx,L)); % 均值为0方差为1的高斯白噪声n n=sqrt(1/2)*(randn(rx,L)+i*randn(rx,L)); % 未叠加噪声的接收信号R R=zeros(rx,L); for k=1:L R(:,k)=sqrt(1/tx)*H(:,:,k)*X(:,k); end %tx=4rx=4,MMSE-SIC========================================================= % MMSE-SIC(ordered)======================================================= berms4=[]; 'MMSE-SIC' for m=SNR m snr=10^(m/10); R_noised=R+sqrt(1/snr)*n; x=[]; for t=1:L r=R_noised(:,t); HH=H(:,:,t); G=pinv(HH); S=[1:tx]; xtemp=zeros(tx,1); for k=1:tx [wki,ki]=minnorm(G); w=inv(HH'*HH+(1/snr)*eye(tx-k+1))*HH'; y=w(ki,:)*r; xtemp(S(ki))=(real(y)>=0)-(real(y)<0)+0+i*((imag(y)>=0)-(imag(y)<0)+0); r=r-sqrt(1/2/tx)*xtemp(S(ki))*H(:,S(ki),t); HH(:,ki)=[]; S(ki)=[]; G=pinv(HH); end x=[x,xtemp]; end xi=real(x); xq=imag(x); ai=zeros(tx,L); aq=zeros(tx,L); for k=1:tx ai(k:tx:end)=(xi(k:tx:end)+1)/2; aq(k:tx:end)=(xq(k:tx:end)+1)/2; end a=zeros(2*tx*L,1); a(1:2:end)=ai; a(2:2:end)=aq; [errbit,temp_ber]=biterr(A,a); berms4=[berms4,temp_ber]; end figure semilogy(SNR,berms4,'s- r') %tx=4,rx=4,ML===================================================================== berml4=[]; 'ML' for m=SNR m snr=10^(m/10); R_noised=R+sqrt(1/snr)*n; x=[]; for t=1:L r=R_noised(:,t); xtemp=zeros(tx,1); S={}; kk=1; for p = 1:4 for q = 1:4 for pp=1:4 for qq=1:4 temp((p-1)*64+(q-1)*16+(pp-1)*4+qq) = norm(r-H(:,:,t)*sqrt(1/2/tx)*[table(p);table(q);table(pp);table(qq)]); S{kk}=[p q pp qq]; kk=kk+1; end end end end [val,ind] = min(temp); p=S{ind}(1); q=S{ind}(2); pp=S{ind}(3); qq=S{ind}(4); xtemp = [table(p);table(q);table(pp);table(qq)]; x=[x,xtemp]; end xi=real(x); xq=imag(x); ai=zeros(tx,L); aq=zeros(tx,L); for k=1:tx ai(k:tx:end)=(xi(k:tx:end)+1)/2; aq(k:tx:end)=(xq(k:tx:end)+1)/2; end a=zeros(2*tx*L,1); a(1:2:end)=ai; a(2:2:end)=aq; [errbit,temp_ber]=biterr(A,a); berml4=[berml4,temp_ber]; end hold on semilogy(SNR,berml4,'s- g'),grid on xlabel('SNR(dB)'); ylabel('误比特率'); title('VBLAST ML检测 (QPSK调制)') legend('tx=4,rx=4,MMSE-SIC','tx=4,rx=4,ML')