alamouti_space_frequency_coding1.m

space time frequency coding-alamouti scheme

clc;
clear all;
close all;



N=10;

% fft_size=512;
% cp=64;

s00=randsrc(1,N*512);  %% BPSK modulation %%





l=1;

    for k=1:2560
    
        s01(l)=s00(l);
        s01(l+1)=-conj(s00(l+1));
    
        s11(l)=s00(l+1);
        s11(l+1)=conj(s00(l));
    
        l=l+2;
        
    end

   
    
    for i=1:10
   
        s0(i,:)=s01((((i-1)*512)+1):(i*512));
        s1(i,:)=s11((((i-1)*512)+1):(i*512));
        
    end

for snr=1:1:30
    
    for monte=1:1:10
       
        
        for a=1:4
            
            X1=randn(1,10);
            Y1=randn(1,10);

            ch(a,:)=channel(X1,Y1,10);                        
            
        end
        
            h0=ch(1,:);
            h1=ch(2,:);
            h2=ch(3,:);
            h3=ch(4,:);
           
        for i=1:10
                        
            t(1,((i-1)*512)+1:(i*512))=s0(i,1:512);
            t(2,((i-1)*512)+1:(i*512))=s1(i,1:512);  
                        
           
        end
 
        r1=(sqrt(1/2)*t(1,1:end));
        r2=(sqrt(1/2)*t(2,1:end));
        
        for i=1:10
        
            r11(i,:)=h0(i)*r1(1,((i-1)*512+1):(i*512));
            r22(i,:)=h1(i)*r2(1,((i-1)*512+1):(i*512));
            r33(i,:)=h2(i)*r1(1,((i-1)*512+1):(i*512));
            r44(i,:)=h3(i)*r2(1,((i-1)*512+1):(i*512));
            
            r01(i,:)=ifft(r11(i,:),512);
            r02(i,:)=ifft(r22(i,:),512);
            r03(i,:)=ifft(r33(i,:),512);
            r04(i,:)=ifft(r44(i,:),512);

        
            r1r(i,:)=[r01(i,512-64+1:512),r01(i,1:512)];
            r2r(i,:)=[r02(i,512-64+1:512),r02(i,1:512)];
            r3r(i,:)=[r03(i,512-64+1:512),r03(i,1:512)];            
            r4r(i,:)=[r04(i,512-64+1:512),r04(i,1:512)];
            
            
        end
        
 %%----------------------------------------------------------------------%%
                          %% ALAMOUTI scheme (SPACE FREQUENCY ENCODING) %%
 %%----------------------------------------------------------------------%% 
                          
                        %% TWO TX AND ONE RX %%
                            
       
        
       
        
        for a=1:10
            
            p1=(r1r(a,:)*r1r(a,:)')/length(r1r(a,:));
            p2=(r2r(a,:)*r2r(a,:)')/length(r2r(a,:));
            p3=(r3r(a,:)*r3r(a,:)')/length(r3r(a,:));
            p4=(r2r(a,:)*r2r(a,:)')/length(r2r(a,:));
            
            n1(a,:)=noise(p1,snr,(1*(512+64)));
            n2(a,:)=noise(p2,snr,(1*(512+64)));
            n3(a,:)=noise(p3,snr,(1*(512+64)));
            n4(a,:)=noise(p4,snr,(1*(512+64)));
                
            rr1(a,:)=r1r(a,:)+n1(a,:);
            rr2(a,:)=r2r(a,:)+n2(a,:);
            rr3(a,:)=r3r(a,:)+n3(a,:);
            rr4(a,:)=r4r(a,:)+n4(a,:);
            
            rx1(a,:)=rr1(a,:)+rr2(a,:);
            rx2(a,:)=rr3(a,:)+rr4(a,:);
            
            rx01(a,:)=fft(rx1(a,65:576),512);
            rx02(a,:)=fft(rx2(a,65:576),512);
            
        end
        
%         m=0;
%         
%         for i=1:1
%             
%             oro00(i,:)=r(1,(m*512)+1:(i*512));        
%             
%             %oro01(i,:)=t(2,(m*512)+1:(i*512));
%         
%             %or00(i,:)=[oro00(i,(512-64+1):512),oro00(i,1:512)]+n(1,((m*576)+1):(i*576));
%             
%             %or01(i,:)=[oro01(i,(512-64+1):512),oro01(i,1:512)]+n(2,((m*576)+1):(i*576));
%         
%             r00(i,:)=fft(r(i,65:576),512);
%             
%             %r01(i,:)=fft(or01(i,65:576),512);
%                                 
%             m=m+1;
%         end
        
        for k=1:10

            for i=1:2:512
            
                sest3(k,i)=(conj(h0(k))*rx01(k,i))+(h1(k)*conj(rx01(k,i+1)))+(conj(h2(k))*rx02(k,i+1))+(h3(k)*conj(rx02(k,i+1)));
                sest3(k,i+1)=(conj(h1(k))*rx01(k,i))-(h0(k)*conj(rx01(k,i+1)))+(conj(h3(k))*rx02(k,i+1))-(h2(k)*conj(rx02(k,i+1)));                         
            
            end
        end

        for i=1:10
            sest(1,((i-1)*512+1):(i*512))=sest3(i,:);
        end
                    %% SIGNAL ESTIMATION %%
                    
                for i=1:1:(1*512)
                    
                    
                    if ((dist(sest(i),-1))<(dist(sest(i),1)))
                       decision(i)=-1;
                    else
                        decision(i)=1;
                    end                                                            
                    

                end
                
                    %% ERROR CALCULATION %%
        
        error1=0;
        error2=0;
        error3=0;
        error4=0;
        error5=0;
        error6=0;
        
                for i=1:1:(1*512)
                    
                    
                    if (decision(i)~=s00(i))
                       error3=error3+1;
                    end                                        
                    
                end
                
                
             
            ber3(monte)=((error3)/(10*512));
            
 

    end
    

    pb3(snr)=mean(ber3);
    

    
    
end

snr=1:30;



semilogy(snr,pb3,'-bh','LineWidth',2,... 
                       'MarkerEdgeColor','k',...
                       'MarkerFaceColor','y',...
                       'MarkerSize',5);
hold on;  



grid on;
hold on;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%55
N=10;
fft_size=512;
cp=64;

s00=randsrc(1,N*256);  %% BPSK modulation %%
s01=randsrc(1,N*256);  %% BPSK modulation %%


i=1;
l=1;
m=0;

for l=1:1

    for k=1:256
    
        s0(l,i)=s00((m*256)+k);
        s0(l,(i+1))=-conj(s01((m*256)+k));
    
        s1(l,i)=s01((m*256)+k);
        s1(l,i+1)=conj(s00((m*256)+k));
    
        i=i+2;
    
    end
    m=m+1;
end

for snr=1:1:50
    
    for monte=1:1:1000
       
        
        for a=1:4
            
            X1=randn(1,512);
            Y1=randn(1,512);

            ch(a,:)=channel(X1,Y1,512);                        
            
        end
        
            h0=ch(1,1);
            h1=ch(2,1);
            h2=ch(3,1);            
            h3=ch(4,1);
            
        
 %%----------------------------------------------------------------------%%
                          %% MRRC scheme %%
 %%----------------------------------------------------------------------%%  
    
%         r(1,:)=(h0*s0);       %% antenna zero %%
%         
%         r(2,:)=(h1*s0);       %% antenna one %%
%         
%         r(3,:)=(h2*s0);       %% antenna two %%
%         
%         r(4,:)=(h3*s0);       %% antenna three %%
%         
%         
%         for a=1:4
%             
%             p=(r(a,:)*r(a,:)')/length(r(a,:));
%             
%             n0(a,:)=noise(p,snr,(512+64));
%             
%         end
%         
%         
%             oro0=ifft(r(1,:),512);
%             oro1=ifft(r(2,:),512);
%             oro2=ifft(r(3,:),512);
%             oro3=ifft(r(4,:),512);
%             
%             or0=[oro0((512-64+1):512),oro0(1:512)]+n0(1,:);
%             
%             or1=[oro0((512-64+1):512),oro0(1:512)]+n0(1,:);
%             
%             or2=[oro0((512-64+1):512),oro0(1:512)]+n0(1,:);
%             
%             or3=[oro0((512-64+1):512),oro0(1:512)]+n0(1,:);
%             
%             r0=fft(or0(65:576),512);            
%             r1=fft(or1(65:576),512);
%             r2=fft(or2(65:576),512);
%             r3=fft(or3(65:576),512);
%         
%         sest1=(conj(h0).*r0)+(conj(h1).*r1);     %% Two branch MRRC (ONE TX AND TWO RX) %%
%         sest2=(conj(h0).*r0)+(conj(h1).*r1)+(conj(h2).*r2)+(conj(h3).*r3);   %% Two branch MRRC (ONE TX AND FOUR RX) %%
%       
 %%----------------------------------------------------------------------%%
                          %% ALAMOUTI scheme (SPACE FREQUENCY ENCODING) %%
 %%----------------------------------------------------------------------%% 
                          
                        %% TWO TX AND ONE RX %%
                            
        rr(1,:)=(sqrt(1/2)*(h0*s0))+(sqrt(1/2)*(h1*s1));
        rr(2,:)=(sqrt(1/2)*(((-1)*h0)*conj(s1)))+(sqrt(1/2)*(h1*conj(s0)));
        
        p=0;
        
        for a=1:2
            
            p=(rr(a,:)*rr(a,:)')/length(rr(a,:));
            
            n1(a,:)=noise(p,snr,(512+64));
        end
            
        oro00=ifft(rr(1,:),512);        
        oro01=ifft(rr(2,:),512);
        
        or00=[oro00((512-64+1):512),oro00(1:512)]+n1(1,:);
        or01=[oro01((512-64+1):512),oro01(1:512)]+n1(2,:);
        
        r00=fft(or00(65:576),512);
        r01=fft(or01(65:576),512);
        
        sest3=(conj(h0)*r00)+(h1*conj(r01));
        sest4=(conj(h1)*r00)-(h0*conj(r01)); 
        
                         %% TWO TX AND TWO RX %%
        
%         rrr(1,:)=(sqrt(1/2)*(h0*s0))+(sqrt(1/2)*(h1*s1));
%         rrr(2,:)=(sqrt(1/2)*(((-1)*h0)*conj(s1)))+(sqrt(1/2)*(h1*conj(s0)));
%         rrr(3,:)=(sqrt(1/2)*(h2*s0))+(sqrt(1/2)*(h3*s1));
%         rrr(4,:)=(sqrt(1/2)*(((-1)*h2)*conj(s1)))+(sqrt(1/2)*(h3*conj(s0)));
%         
%         p=0;
%         
%         for a=1:4
%             
%             p=(rrr(a,:)*rrr(a,:)')/length(rrr(a,:));
%             
%             n2(a,:)=noise(p,snr,512);
%         end
%         
%         or10=ifft(rrr(1,:),512)+n2(1,:);
%         
%         or11=ifft(rrr(2,:),512)+n2(2,:);
%         
%         or12=ifft(rrr(3,:),512)+n2(3,:);
%         
%         or13=ifft(rrr(4,:),512)+n2(4,:);
%         
%         r10=fft(or10,512);
%         r11=fft(or11,512);
%         r12=fft(or12,512);
%         r13=fft(or13,512);
%         
%         
%         
%         sest5=(conj(h0)*r10)+(h1*conj(r11))+(conj(h2)*r12)+(h3*conj(r13));
%         sest6=(conj(h1)*r10)-(h0*conj(r11))+(conj(h3)*r12)-(h2*conj(r13));  
        
                    %% SIGNAL ESTIMATION %%
                    
                for i=1:1:N
                    
%                     if ((dist(sest1(i),-1))<(dist(sest1(i),1)))
%                        decision1(i)=-1;
%                     else
%                        decision1(i)=1;                    
%                     end
%                     
%                     if ((dist(sest2(i),-1))<(dist(sest2(i),1)))
%                        decision2(i)=-1;
%                     else
%                        decision2(i)=1;                    
%                     end
                    
                    if ((dist(sest3(i),-1))<(dist(sest3(i),1)))
                       decision3(i)=-1;
                    else
                        decision3(i)=1;
                    end
                    
                    
                    if ((dist(sest4(i),-1))<(dist(sest4(i),1)))
                       decision4(i)=-1;
                    else
                       decision4(i)=1;                    
                    end
                    
%                     if ((dist(sest5(i),-1))<(dist(sest5(i),1)))
%                        decision5(i)=-1;
%                     else
%                        decision5(i)=1;                    
%                     end
%                     
%                     if ((dist(sest6(i),-1))<(dist(sest6(i),1)))
%                        decision6(i)=-1;
%                     else
%                        decision6(i)=1;                    
%                     end

                end
                
                    %% ERROR CALCULATION %%
        
        error1=0;
        error2=0;
        error3=0;
        error4=0;
        error5=0;
        error6=0;
        
                for i=1:1:N
                    
%                     if (decision1(i)~=s0(1,i))
%                        error1=error1+1;
%                     end
%                     
%                     if (decision2(i)~=s0(1,i))
%                        error2=error2+1;
%                     end
                    
                    if (decision3(i)~=s0(1,i))
                       error3=error3+1;
                    end

                    if (decision4(i)~=s1(1,i))
                       error4=error4+1;
                    end
                    
%                     if (decision5(i)~=s0(1,i))
%                        error5=error5+1;
%                     end
% 
%                     if (decision6(i)~=s1(1,i))
%                        error6=error6+1;
%                     end
                    
                end
                
                
%             ber1(monte)=(error1/512);
%             
%             ber2(monte)=(error2/512);
%             
            ber3(monte)=((error3+error4)/(512));% semilogy(snr,pb4,'^--','LineWidth',2,... 
%                       'MarkerEdgeColor','k',...
%                       'MarkerFaceColor','r',...
%                       'MarkerSize',5);
% hold on;

            
%             ber4(monte)=((error5+error6)/(1024));
            
 

    end
    
%     pb1(snr)=mean(ber1);
%     
%     pb2(snr)=mean(ber2);
%     
    pb3(snr)=mean(ber3);
    
%     pb4(snr)=mean(ber4);
    
    
end

snr=1:30;

% semilogy(snr,pb1,'-rd','LineWidth',2,...
%                        'MarkerEdgeColor','k',...
%                        'MarkerFaceColor','g',...
%                        'MarkerSize',5);
% hold on;
% 
% semilogy(snr,pb2,'-gs','LineWidth',2,...
%                        'MarkerEdgeColor','k',...
%                        'MarkerFaceColor','c',...
%                        'MarkerSize',5);
% hold on;

semilogy(snr,pb3,'-bh','LineWidth',2,... 
                       'MarkerEdgeColor','k',...
                       'MarkerFaceColor','y',...
                       'MarkerSize',5);
hold on;  

% semilogy(snr,pb4,'^--','LineWidth',2,... 
%                       'MarkerEdgeColor','k',...
%                       'MarkerFaceColor','r',...
%                       'MarkerSize',5);
% hold on;
                      


% semilogy(snr,pb1,'r*-');
% hold on;
% semilogy(snr,pb2,'g*-');
% hold on;
% semilogy(snr,pb3,'k^-');
% hold on;
% semilogy(snr,pb4,'ko-');

grid on;
hold on;