Alamouti空时码_空时码_alamouti多天线_mimo_源码

function error_rate=kechengsheji(n,SNR,N_Receiver) %______________________信源部分________________________% c_source=rand(n,1); c_source(c_source==1)=[];%剔除1，强制[0,0.5)和[0.5,1)等概率 c_source(c_source<0.5)=-1;%等概率前提近似取等号，免去信源编码;双极性。 c_source(c_source>=0.5)=1; n_deng=length(c_source);%重新数出个数 if mod(n_deng,2) ~= 0 c_source(1)=[]; n_deng=n_deng-1;%强制c_source为偶数个 end c_element=c_source; c_length=n_deng;%结构体c储存 % %不进行信道编码，防止对误码性能产生影响 % %_____________________________________________________% %____________________QPSK调制_________________________% %B_map=[1+1i 1-1i -1-1i -1+1i];%%%%B方式调制 n_phase=c_length/2; c_IQ=reshape(c_element,n_phase,2);%串并转换 c_phase=((c_IQ(:,1)*1i)+(c_IQ(:,2)));%相位映射 %scatterplot(c_phase) B_jugle=[[1+1i;1+1i],[1+1i;1-1i],[1+1i;-1-1i],[1+1i;-1+1i], ... [1-1i;1+1i],[1-1i;1-1i],[1-1i;-1-1i],[1-1i;-1+1i], ... [-1-1i;1+1i],[-1-1i;1-1i],[-1-1i;-1-1i],[-1-1i;-1+1i], ... [-1+1i;1+1i],[-1+1i;1-1i],[-1+1i;-1-1i],[-1+1i;-1+1i]]; %_____________________________________________________% %____________________天线发射_________________________% n_antenna=2;%发射天线数目为二 n_each_antenna=n_phase/n_antenna; antenna=reshape(c_phase,n_each_antenna,n_antenna); c_STBC = cell(n_each_antenna,1);%预设大小 %X=cell(n_each_antenna,1); for i=1:n_each_antenna c_STBC{i}=[antenna(i,:);[-1*conj(antenna(i,2)),conj(antenna(i,1))]]; %X{i}=antenna(i,:)'; end %_____________________________________________________% %______________________分集合并_MRC合并_____________________% R_comphase_s=zeros(2*n_each_antenna,1); % Alpha_s=zeros(n_each_antenna,N_Receiver); H_comphase_s=zeros(2*n_each_antenna,2); for k=1:N_Receiver [R_comphase,H_comphase]=pass_rei(n_each_antenna,c_STBC,SNR); R_comphase_s=R_comphase_s+R_comphase; % Alpha_s(:,k)=alpha; H_comphase_s(:,1)=H_comphase_s(:,1)+H_comphase(:,1); H_comphase_s(:,2)=H_comphase_s(:,2)+H_comphase(:,2); end R=cell(n_each_antenna,1); H=cell(n_each_antenna,1); for i=1:n_each_antenna odd=2*i-1; even=2*i; R{i}= [R_comphase_s(odd);R_comphase_s(even)]; H{i}= [H_comphase_s(odd,:);H_comphase_s(even,:)]; end % for i=1:n_each_antenna % R{i}= [R_comphase_s(2*i-1,:)*Alpha_s(i,:)';conj(R_comphase_s(2*i,:)*Alpha_s(i,:))']/sum(Alpha_s(i,:)); % for k=1:N_Receiver % H{i}(1,:)=H_comphase_s % end % end %_____________________________________________________% %_________________________判决________________________% x=zeros(n_each_antenna,2);%定义大小 for i=1:n_each_antenna jugle=[norm(R{i}-H{i}*[1+1i;1+1i]),norm(R{i}-H{i}*[1+1i;1-1i]),norm(R{i}-H{i}*[1+1i;-1-1i]),norm(R{i}-H{i}*[1+1i;-1+1i]), ... norm(R{i}-H{i}*[1-1i;1+1i]),norm(R{i}-H{i}*[1-1i;1-1i]),norm(R{i}-H{i}*[1-1i;-1-1i]),norm(R{i}-H{i}*[1-1i;-1+1i]), ... norm(R{i}-H{i}*[-1-1i;1+1i]),norm(R{i}-H{i}*[-1-1i;1-1i]),norm(R{i}-H{i}*[-1-1i;-1-1i]),norm(R{i}-H{i}*[-1-1i;-1+1i]), ... norm(R{i}-H{i}*[-1+1i;1+1i]),norm(R{i}-H{i}*[-1+1i;1-1i]),norm(R{i}-H{i}*[-1+1i;-1-1i]),norm(R{i}-H{i}*[-1+1i;-1+1i])]; x(i,:)=B_jugle(:,jugle==min(jugle))';%%%按书本方式解调 end x=reshape(x,1,n_phase)'; x_comp=x-c_phase; x_comp(x_comp~=0)=1; error_rate=sum(x_comp)/n_phase;%误码率 %_____________________________________________________% end function [R_comphase,H_comphase]=pass_rei(n_each_antenna,c_STBC,SNR) %____________________过瑞利信道_______________________% %%r=cell(n_each_antenna,1); %%H=cell(n_each_antenna,1); n_each_antenna_c2=n_each_antenna*2; H_comphase=zeros(n_each_antenna_c2,2); %%R=cell(n_each_antenna,1); Noise=zeros(n_each_antenna_c2,1); R_comphase_nn=zeros(n_each_antenna_c2,1);% R_comphase=zeros(n_each_antenna_c2,1); P_noise=zeros(n_each_antenna_c2,1); alpha=zeros(n_each_antenna_c2,1); for i=1:n_each_antenna odd=2*i-1; even=2*i; chan_1=rayleighchan; %scatterplot(r_rayleigh) chan_2=rayleighchan; %%h=[chan_1.PathGains;chan_2.PathGains]; h_comphase=[norm(chan_1.PathGains);norm(chan_2.PathGains)];%同相 %%r{i}=c_STBC{i}*h; %%H{i}=[chan_1.PathGains,chan_2.PathGains;conj(chan_2.PathGains),-conj(chan_1.PathGains)]; %%R{i}=[awgn(r{i}(1),SNR);conj(awgn(r{i}(2),SNR))]; %scatterplot(r_pro) %%Noise{i}= [R{i}(1);conj(R{i}(2))]- r{i}; %%R_comphase(2*i-1)=c_STBC{i}(1,:)*h_comphase+Noise{i}(1); %%R_comphase(2*i)=conj(c_STBC{i}(2,:)*h_comphase+Noise{i}(2)); R_comphase_nn(odd)=c_STBC{i}(1,:)*h_comphase;% R_comphase_nn(even)=c_STBC{i}(2,:)*h_comphase;% R_comphase(odd)=awgn(R_comphase_nn(odd),SNR);%同相过后的ri R_comphase(even)=awgn(R_comphase_nn(even),SNR);% %Noise{i}= [R_comphase(odd)-R_comphase_nn(odd);R_comphase(even)-R_comphase(even)];% Noise(odd)=R_comphase(odd)-R_comphase_nn(odd); Noise(even)=R_comphase(even)-R_comphase_nn(even); P_noise(odd)=norm(Noise(odd))^2;%噪声功率Nk P_noise(even)=norm(Noise(even))^2; R_comphase(even)=conj(R_comphase(even)); %alpha(i)=norm([R_comphase(odd),R_comphase(even)])/P_noise(i);%alpha alpha(odd)=norm(R_comphase(odd))/P_noise(odd);%%正比于rk/Nk alpha(even)=norm(R_comphase(even))/P_noise(even);% % alpha(i)=norm(R_comphase_nn(odd));%奇 偶等大 R_comphase(odd)=R_comphase(odd)*alpha(odd); R_comphase(even)=R_comphase(even)*alpha(even); H_comphase(odd,:)=[h_comphase(1),h_comphase(2)]*alpha(odd); H_comphase(even,:)=[h_comphase(2),-h_comphase(1)]*alpha(even); end %_____________________________________________________% %scatterplot(reshape(cell2mat(r),1,n_phase)) %scatterplot(reshape(cell2mat(R),1,n_phase)) %scatterplot(reshape(cell2mat(R_comphase),1,n_phase)) end %______________________信源部分________________________% c_source=rand(n,1); c_source(c_source==1)=[];%剔除1，强制[0,0.5)和[0.5,1)等概率 c_source(c_source<0.5)=-1;%等概率前提近似取等号，免去信源编码;双极性。 c_source(c_source>=0.5)=1; n_deng=length(c_source);%重新数出个数 if mod(n_deng,2) ~= 0 c_source(1)=[]; n_deng=n_deng-1;%强制c_source为偶数个 end c_element=c_source; c_length=n_deng;%结构体c储存 % %不进行信道编码，防止对误码性能产生影响 % %_____________________________________________________% %____________________QPSK调制_________________________% %B_map=[1+1i 1-1i -1-1i -1+1i];%%%%B方式调制 n_phase=c_length/2; c_IQ=reshape(c_element,n_phase,2);%串并转换 c_phase=((c_IQ(:,1)*1i)+(c_IQ(:,2)));%相位映射 %scatterplot(c_phase) B_jugle=[[1+1i;1+1i],[1+1i;1-1i],[1+1i;-1-1i],[1+1i;-1+1i], ... [1-1i;1+1i],[1-1i;1-1i],[1-1i;-1-1i],[1-1i;-1+1i], ... [-1-1i;1+1i],[-1-1i;1-1i],[-1-1i;-1-1i],[-1-1i;-1+1i], ... [-1+1i;1+1i],[-1+1i;1-1i],[-1+1i;-1-1i],[-1+1i;-1+1i]]; %_____________________________________________________% %____________________天线发射_________________________% n_antenna=2;%发射天线数目为二 n_each_antenna=n_phase/n_antenna; antenna=reshape(c_phase,n_each_antenna,n_antenna); c_STBC = cell(n_each_antenna,1);%预设大小 %X=cell(n_each_antenna,1); for i=1:n_each_antenna c_STBC{i}=[antenna(i,:);[-1*conj(antenna(i,2)),conj(antenna(i,1))]]; %X{i}=antenna(i,:)'; end %_____________________________________________________% %______________________分集合并_MRC合并_____________________% R_comphase_s=zeros(2*n_each_antenna