fig_ml_nearfar_gold.m

张贤达老师 通信信号处理4－9章的程序 这本书是张老师的经典之作。

% Fig_ml_nearfar_gold

clear
N=31;                            % the spreading gain
SourceNum=10000;                  % the number of source signal
RunningTime=10;                 % the iteration number
userNum=10;                      % the total number of users
M = 1;                           % the number of desired user
% power=[20 30 30 30 30 40 40 40 50 50]-20;          % the emitting power of all the usersr
power = zeros(1,10);
A = diag(10.^(power/20));

spreadingCode=goldcode(log2(N+1))/sqrt(N);            % generate spreading code using the function goldcode
spreadingCode=spreadingCode(:,2:userNum+1);

BITS = makebinary(userNum);           % here, we should list all the possible combination of the users' data  
for kk = 1:5
    SNR = (kk-1)*3;
for j=1:RunningTime                                             % begin to circulation 
    spreadingCode = sign(randn(N,userNum))/sqrt(N);
    R = spreadingCode'*spreadingCode;
    noise=randn(SourceNum*N,1)/(10^(SNR/20));                  % generate noise
    symbol=sign(rand(userNum,SourceNum)-0.5);                       % generate bipolar signal
    source=diag(10.^(power/20))*symbol;
    SpreadedSignal=spreadingCode*source;
    for i=1:SourceNum
        for k = 1:userNum
            temp(:,k) = source(k,i)*spreadingCode(:,k);
        end
        ReceivedSignal=sum(temp,2)+noise(1+(i-1)*N:i*N);     % calculate the received signal, that passs the channel
        r = spreadingCode'*ReceivedSignal;
        b1(:,i) = jml(r,R,A,1,BITS);                         % run the ML detector for each iteration
    end
    errorratio1(j,kk) = length(find(b1(1:M,:)~=symbol(1:M,:)))/SourceNum/M;        % the BER    
end
end
FONTSIZE=0.315;         % 单位为厘米;  
LINEWIDTH_AXES=1.2;%140/42;  % corresponding to 0.140mm 
LINEWIDTH_WAVE=0.5;%180/42;  % corresponding to 0.180mm
figNumber=figure('Name','ML no nearfar and nearfar gold code', 'Visible','on');
set(gcf,'Color','white');
semilogy(0:3:12,mean(errorratio1),'r-+','LineWidth',LINEWIDTH_WAVE)
hold on
grid on
xlabel('SNR (dB)','FontUnits','centimeters','FontName','Times New Roman','FontSize',FONTSIZE);  
ylabel('BER','FontUnits','centimeters','FontName','Times New Roman','FontSize',FONTSIZE);
title('\bf ML Multiuser Detector in a Nearfar Environment (Gold Code)','Color','blue','FontUnits','centimeters','FontName','Times New Roman','FontSize',FONTSIZE*1.2);
set(gca,'XColor','blue','YColor','blue','FontUnits','centimeters','FontName','Times New Roman','FontSize',FONTSIZE,'LineWidth',LINEWIDTH_AXES);
set(figNumber,'PaperPosition',[0.634518 6.34518 20.3046*0.8 15.2284*0.8]);     %Shrink the figure size  







clear
N=31;                            % the spreading gain
SourceNum=10000;                  % the number of source signal
RunningTime=10;                 % the iteration number
userNum=10;                      % the total number of users
M = 1;                           % the number of desired user
power=[20 30 30 30 30 40 40 40 50 50]-20;          % the emitting power of all the usersr
% power = zeros(1,10);
A = diag(10.^(power/20));

spreadingCode=goldcode(log2(N+1))/sqrt(N);            % generate spreading code using the function goldcode
spreadingCode=spreadingCode(:,2:userNum+1);

BITS = makebinary(userNum);           % here, we should list all the possible combination of the users' data  
for kk = 1:5
    SNR = (kk-1)*3;
for j=1:RunningTime                                             % begin to circulation 
    spreadingCode = sign(randn(N,userNum))/sqrt(N);
    R = spreadingCode'*spreadingCode;
    noise=randn(SourceNum*N,1)/(10^(SNR/20));                  % generate noise
    symbol=sign(rand(userNum,SourceNum)-0.5);                       % generate bipolar signal
    source=diag(10.^(power/20))*symbol;
    SpreadedSignal=spreadingCode*source;
    for i=1:SourceNum
        for k = 1:userNum
            temp(:,k) = source(k,i)*spreadingCode(:,k);
        end
        ReceivedSignal=sum(temp,2)+noise(1+(i-1)*N:i*N);     % calculate the received signal, that passs the channel
        r = spreadingCode'*ReceivedSignal;
        b1(:,i) = jml(r,R,A,1,BITS);                         % run the ML detector for each iteration
    end
    errorratio1(j,kk) = length(find(b1(1:M,:)~=symbol(1:M,:)))/SourceNum/M;        % the BER    
end
end


FONTSIZE=0.315;         % 单位为厘米;  
LINEWIDTH_AXES=1.2;%140/42;  % corresponding to 0.140mm 
LINEWIDTH_WAVE=0.5;%180/42;  % corresponding to 0.180mm
semilogy(0:3:12,mean(errorratio1),'b-+','LineWidth',LINEWIDTH_WAVE)