MATLAB program for plotting the power spectral densities of NRZ unipolar, NRZ polar, NRZ bipolar and Manchester polar line coding schemes.

MATLAB Program:

%Code:

f=-1:0.01:1;

Tb=2;

a=4;

x1=(sinc(f*Tb)).^2;

x2=x1*Tb*((a^2)/4);

x=x1*Tb*(a^2);

z=(f==0);

z1=((a^2)/4)*z;

x_2=x2+z1;

v=(sin(pi*f*Tb).^2);

x_3=x.*v;

vm=(sinc(f*Tb/2)).^2;

vm1=(sin(pi*f*Tb/2).^2);

x_4=(a^2)*Tb*vm.*vm1;

plot(f,x,'r',f,x_2,'g',f,x_3,'b',f,x_4,'c');

legend('NRZ-Polar','NRZ-Unipolar','NRZBipolar','Manchester polar');

Outputs: