我编写了这段代码，用于以图形方式比较手动计算的BER和理论BER .

手动计算的BER（错误）总是1x1值，我希望它作为对应于SNR值的值范围 .

我也替换了这一行：

err=error+1;

用这一行：

err(k)=error+1;

仍然没有工作 .

任何人都可以解决这个问题吗？

这是代码：

N=100;                               % number of bits

SNR=0:1:10;                          % Different values for SNR

err=zeros(1:length(SNR));            % Initilizing calculated error for 
                                     % different SNR values

for k=1:1:length(SNR)

    N0(k)=10^(-SNR(k)/10);            % Calculating the noise level

    s=randn(1,N)>.5;                 % generating random number of logic bits
                                     % with equal probability 0.5    
    s=2*s-1;                         % Generating BPSK sequence between logic 1 , -1

                                     % Generating real random noise with SD of 0.1
    n = sqrt(N0(k)/2)*(randn(1,N) + j*randn(1,N));   

    r=s+n;                           % Noisy signal 

    rd=zeros(1,N);                   % Initializing Detected signal

        for i=1:1:N

            if(r(i)>0)              % Comparing detected signal against a threshold
                rd(i)=1;
            else
                rd(i)=0;         
            end
        end

    error=0;

        for j=1:1:N                 % calculating BER

            if(abs(rd(j)-s(j))==1)
                error=error+1;        
            end
        end


        err=error+1;                   % calculated error for this value of SNR

end

th_err=.5*erfc(sqrt(10.^(SNR/10)));   % Theoretical BER

semilogy(SNR,th_err,'*r');grid on;title('Bit error rate for BPSK');xlabel('Eb/N0');ylabel('Theoritical BER');
matlab ber