ebn0=[-1.6 0 3 6 9 12 15 18 21 24 27 30 33 36];
%eficienta benzii pag 602 Haykin;


x=10.^(.1*ebn0);
yy=.8:.1:.9;
zz=1:1:12; w=[yy zz];%cb=10.^w;
cb1=x.*w;
cb2=log2(1+cb1);
semilogy(ebn0,cb2)