mimo1.asv

移动通信中的MIMO信道模型

clear all;
close all;
% %Gaussian
Roul=zeros(3,9);RR=zeros(1,9);iters=60;
for num=1:iters
%     N=[80 320 800 3200];
    N=[8 80 100];
    d=0:8;
   lamda=3*1e8/(9*1e8); 
   m=10*pi/180;
   sigma=3*pi/180;   
   S=(erf((pi-m)/(sqrt(2)*sigma))-erf((-pi-m)/(sqrt(2)*sigma)))/2;
   roul=zeros(length(N),length(d));
   for n=1:length(N)
         for i=1:length(d)
             for k=1:N(n)
                 theta(k)=sqrt(2)*sigma*erfinv(2*rand(1)-1)+m;
                 delta(k)=2*pi*d(i)*sin(theta(k))/lamda;
             end
             roul(n,i)=sum(exp(-j*delta))/N(n);
         end
   end
for ii=1:length(d)
    thetar=-pi:1/3200:pi;
    f=(1/(sqrt(2*pi)*sigma*S)).*exp(-(thetar-m).^2./(2*sigma^2));
    R(ii)=sum(exp(-j*2*pi*d(ii).*sin(thetar)./lamda).*f)/3200;
end
   Roul=Roul+roul;
   RR=RR+R;
end
Roul=Roul/iters;RR=RR/iters;
Roul(:,1)=1;RR(1)=1;
% plot(d,abs(RR),'-',d,abs(Roul(1,:)),'-*',d,abs(Roul(2,:)),'-.',d,abs(Roul(3,:)),'--',d,abs(Roul(4,:)),':');
% legend('theory','simulation (N=80)','simulation (N=320)','simulation (N=800)','simulation (N=3200)');
plot(d,abs(RR),'-',d,abs(Roul(1,:)),'-*',d,abs(Roul(2,:)),'-.',d,abs(Roul(3,:)),'--');
legend('theory','simulation (N=8)','simulation (N=80)','simulation(N=100)');
xlabel('antenna spacing [1/λ]');
ylabel('spatial correlation');

%laplacian

% Roul=zeros(3,9);RR=zeros(1,9);iters=60;
% for num=1:iters
% %     N=[80 320 800 3200];
%     N=[32 80 100];
%     d=0:8;
%    lamda=3*1e8/(9*1e8); 
%    m=10*pi/180;
%    sigma=9*pi/180;   
%    S=1-exp(-sqrt(2)*pi/sigma)*cosh(sqrt(2)*m/sigma);   
%    roul=zeros(length(N),length(d));
%    for n=1:length(N)
%          for i=1:length(d)
%              for k=1:N(n)
%                  u=rand(1);
%                  if u>=0.5
%                      theta(k)=m-(sigma/sqrt(2))*log(2*(1-u));
%                  else
%                      theta(k)=m+(sigma/sqrt(2))*log(2*u);
%                  end
%                  delta(k)=2*pi*d(i)*sin(theta(k))/lamda;
%              end
%              roul(n,i)=sum(exp(-j*delta))/N(n);
%          end
% %       plot(d,roul);
% %       hold on
%    end
%    for ii=1:length(d)
%        thetar=-pi:1/3200:pi;
%        f=(1/(sqrt(2)*sigma*S)).*exp(-sqrt(2)*abs(thetar-m)./sigma);
%        R(ii)=sum(exp(-j*2*pi*d(ii).*sin(thetar)./lamda).*f)/3200;
%    end
%    Roul=Roul+roul;
%    RR=RR+R;
% end
% Roul=Roul/iters;RR=RR/iters;
% Roul(:,1)=1;RR(1)=1;
% % plot(d,abs(RR),'-',d,abs(Roul(1,:)),'-*',d,abs(Roul(2,:)),'-.',d,abs(Roul(3,:)),'--',d,abs(Roul(4,:)),':');
% % legend('theory','simulation (N=80)','simulation (N=320)','simulation (N=800)','simulation (N=3200)');
% plot(d,abs(RR),'-',d,abs(Roul(1,:)),'-*',d,abs(Roul(2,:)),'-.',d,abs(Roul(3,:)),'--');
% legend('theory','simulation (N=32)','simulation (N=80)','simulation (N=100)');
% xlabel('antenna spacing [1/λ]');
% ylabel('spatial correlation');