DC MATLAB - PCM SYSTEM

Program:

clc;

close all;

clear all;

n=input('enter n value for n-bit PCM system:');

n1=input('enter number of samples in a period:');

L=2^n;

x=0:2*pi/n1:4*pi;

s=8*sin(x);

subplot(3,1,1);

plot(s);

title('analog signal');

ylabel('amplitude--->');

xlabel('time--->');

subplot(3,1,2);

stem(s);

grid on;

title('sampled signal');

ylabel('amplitude--->');

xlabel('time-->');

vmax=8;

vmin=-vmax;

del=(vmax-vmin)/L;

part=vmin:del:vmax;

code=vmin-(del/2):del:vmax+(del/2);

[ind,q]=quantiz(s,part,code);

l1=length(ind);

l2=length(q);

for i=1:l1

    if(ind(i)~=0)

        ind(i)=ind(i)-1;

    end

    i=i+1;

end

for i=1:l2

    if(q(i)==vmin-(del/2))

        q(i)=vmin+(del/2);

    end

end

subplot(3,1,3);

stem(q);

grid on;

title('quantized signal');

ylabel('amplitude-->');

xlabel('time-->');

figure

code=de2bi(ind,'left-msb');

k=1;

for i=1:l1

    for j=1:n

        coded(k)=code(i,j);

        j=j+1;

        k=k+1;

    end

    i=i+1;

end

subplot(2,1,1);

stairs(coded);

grid;

axis([0 100 -2 3]);

title('encoded signal');

ylabel('amplitude-->');

xlabel('time-->');