n=500;
x1=randi([0 15],1,10000); %500 random characters
x2=randi([0 7],1,10000); %500 random characters
x3=randi([0 1],1,10000); %500 random characters
WYN = zeros(3,31);

for j=0:30
    i=30-j;

    y1=qammod(x1,16);
    y2=qammod(x2,8);
    y3=qammod(x3,2);

    y_noise1 = awgn(y1,i,'measured');
    y_noise2 = awgn(y2,i,'measured');
    y_noise3 = awgn(y3,i,'measured');

    z1=qamdemod(y_noise1,16);
    z2=qamdemod(y_noise2,8);
    z3=qamdemod(y_noise3,2);

    blad1 = z1-x1;
    blad2 = z2-x2;
    blad3 = z3-x3;

    licznik1=nnz(blad1);
    licznik2=nnz(blad2);
    licznik3=nnz(blad3);

    WYN(1,i+1)=licznik1/10000;
    WYN(2,i+1)=licznik2/10000;
    WYN(3,i+1)=licznik3/10000;
end
WYN=100*WYN;
X=(0:1:30);
plot(X,WYN(1,:),'r',X,WYN(2,:),'g',X,WYN(3,:),'b');
legend("QAM16","QAM8","QAM2")