MIMO复用技术MATLAB仿真代码

% Alamouti_scheme.m %MIMO-OFDM Wireless Communications with MATLAB㈢ Yong Soo Cho, Jaekwon Kim, Won Young Yang and Chung G. Kang %2010 John Wiley & Sons (Asia) Pte Ltd hold on; fc=1e8; VehicSpd=50; C=3e8; fd=VehicSpd*fc/C; shadow_sigma=3; d=0.5e3; Gt=40; Gr=15; channel_length=100000; fs=30e8; n=1:channel_length; t_interval=1/fs; counter=0.1*fs; L_frame=130; N_Packets=400; % Number of frames/packet and Number of packets NT=2; NR=2; b=2; EbN0dB=[0:5:30]; sq_NT=sqrt(NT); sq2=sqrt(2); for iEbN0dB=1:length(EbN0dB) SNRdB=EbN0dB(iEbN0dB); for i_packet=1:N_Packets msg_symbol=randint(L_frame*b*NT,1); tx_bits=msg_symbol.'; tmp=[]; tmp1=[]; [tmp1,sym_tab,P] = modulator(tx_bits,b); Sig=reshape(tmp1,[],NT); %*** 大尺度 **** pathloss = 32.44+20*log10(d/1000)+20*log10(fc/10^6) - Gr - Gt; % pathloss=10; R1=normrnd(0,shadow_sigma,1,length(Sig(1))); PL1=pathloss+R1; R2=normrnd(0,shadow_sigma,1,length(Sig(1))); PL2=pathloss+R2; X1_fading=Sig(:,1).*sqrt(10.^((-1)*PL1/10)); % 大尺度 X2_fading=Sig(:,2).*sqrt(10.^((-1)*PL2/10)); % 大尺度 %****** 计算高斯噪声方差 ******* Es_average=sum(X1_fading.*conj(X1_fading),1)/L_frame; sigma=sqrt(Es_average/(10^(SNRdB/10))); H=zeros(NT,L_frame,NR); for nt=1:NT for nr=1:NR H(nt,:,nr)=rayleighnew(L_frame,t_interval,fd,counter*nr*nt); end end H1=reshape(H(1,:,:),L_frame,[]); % h11,h12 H2=reshape(H(2,:,:),L_frame,[]); % h21 h22 R1=H1(:,1).*X1_fading+H1(:,2).*X2_fading+sigma*(randn(L_frame,1)+j*randn(L_frame,1)); R2=H2(:,1).*X1_fading+H2(:,2).*X2_fading+sigma*(randn(L_frame,1)+j*randn(L_frame,1)); for iSym=1:L_frame h=[H1(iSym,1) H1(iSym,2);H2(iSym,1) H2(iSym,2)]; W=pinv(h); input=[R1(iSym);R2(iSym)]; output1(iSym)=W(1,:)*input; output2(iSym)=W(2,:)*input; end [Z1_real,Z1_img]=QPSK_denmod(output1); k=1; for i=1:2:2*L_frame Z1_demod(i)=Z1_real(:,k); Z1_demod(i+1)=Z1_img(:,k); k=k+1; end [Z2_real,Z2_img]=QPSK_denmod(output2); k=1; for i=1:2:2*L_frame Z2_demod(i)=Z2_real(:,k); Z2_demod(i+1)=Z2_img(:,k); k=k+1; end output=[Z1_demod Z2_demod]; input=reshape(msg_symbol,1,[]); errorNum(i_packet)=sum(output~=input); disp(['EbN0dB = ' num2str(EbN0dB(iEbN0dB)) '; Packet= ' num2str(i_packet) ';'' error bit = ' num2str(errorNum(i_packet)) ';']); end % End of FOR loop for i_packet errorTotal=sum(errorNum); BER(iEbN0dB) = errorTotal/(N_Packets*L_frame*b); end % End of FOR loop for i_SNR semilogy(EbN0dB,BER,'-*b'); % axis([EbN0dB([1 end]) 1e-8 1e0]); grid on; xlabel('SNR[dB]'); ylabel('BER');