Matlab Practicals for Digital Signal Processing

Program for the generation of unit impulse signal [n] -3 ≥ N ≥ 3 .

clc;

clear all;

close all;

display('Obtaining UNIT IMPULSE signal')

display('Generalized for any value of n')

n = input('enter the value of n = ')

A = linspace(-n,n,(2*n+1))

for i=1:(2*n+1)

    if i==(n+1)

        a(i)=1;

    else

        a(i)=0;

    end

end

    stem(A,a)

    xlabel('value of n')

    title('IMPULSE SIGNAL d(n)')

Q.2 Program for the generation of unit step signal, d[n] = u[n]-u[n-k]

clc;

clear all;

close all;

display('Obtaining UNIT SAMPLE signal using UNIT STEP signals')

display('Generalized for any value of n')

n = input('enter the value of n = ')

A = linspace(-n,n,(2*n+1))

for i=1:(2*n+1)

    if i>=(n+1)

        a(i)=1;

    else

        a(i)=0;

    end

end

for i=1:(2*n+1)

    if i>=(n+1)+1

        b(i)=1;

    else

        b(i)=0;

    end

end

subplot(2,2,1);

stem(A,a);

xlabel('value of n');

title('UNIT STEP SIGNAL U(n)');

subplot(2,2,2);

stem(A,b);

xlabel('value of n');

title('UNIT DELAYED STEP SIGNAL U(n-1)');

subplot(2,2,3);

stem(A,(a-b));

xlabel('value of n');

title('UNIT SAMPLE SIGNAL d(n)');

Q.3  Program for the generation of unit ramp signal r[n] -3 ≥ N ≥ 3 .

clc;

clear all;

close all;

display('Obtaining RAMP signal ')

display('Generalized for any value of n')

n = input('enter the value of n = ')

A = linspace(-n,n,(2*n+1))

for i=1:(2*n+1)

    if i>=(n+1)

        a(i)=i-(n+1);

    else

        a(i)=0;

    end

end

stem(A,a);

xlabel('value of n');

title('UNIT RAMP SIGNAL r(n)');

Q.4  Program for the generation of exponentially signal x[n] -3 ≥ N ≥ 3 .

clc;

clear all;

close all;

display('Obtaining EXPONENTIAL signal ka^n')

display('Generalized for any value of n')

n = input('enter the value of n = ')

k = input('enter the value of k = ')

a = input('enter the value of a = ')

A = linspace(-n,n,(2*n+1))

for i=1:(2*n+1)

    if i>=0

        b(i)=k.*(a.^(i));

    else

        b(i)=0;

    end

end

stem(A,b);

xlabel('value of n');

title('EXPONENTIAL SIGNAL x(n)');

Q.5  Program for the generation of unit cosine & sine signal x[n] -3 ≥ N ≥ 3 .

clc;

clear all;

close all;

display('Obtaining SINE AND COSINE signals ')

display('Generalized for any value of n')

n = input('enter the value of n = ')

t = -n:0.04:n;

x = sin(2*pi*t);

y = cos(2*pi*t);

subplot(2,1,1)

stem(t,x);

xlabel('value of n');

title('SINE SIGNAL x(n)');

subplot(2,1,2)

stem(t,y);

xlabel('value of n');

title('COSINE SIGNAL x(n)');

Q.6  Program for the generation of exponential signal x[n] -3 ≥ N ≥ 3 .

clc;

clear all;

close all;

display('Obtaining EXPONENTIAL signal ka^n')

display('Generalized for any value of n')

n = input('enter the value of n = ')

k = input('enter the value of k = ')

a = input('enter the value of a = ')

A = linspace(-n,n,(2*n+1))

for i = 1:(2*n+1)

    if i>=(n+1)

        b(i)=k.*(a.^(i));

    else if i<=(n+1)

            b(i)=k.*(a.^(i));

        else

        b(i)=0;

    end

    end

end

stem(A,b);

xlabel('value of n');

title('EXPONENTIAL SIGNAL x(n)');

Q.7 Write the a Matlab function to perform on two DT sequence x1[n] & x2[n]

       a. Addition    b. Multiplication    c. Shifting    d. Folding    e. even/odd

clc;

clear all;

close all;

i = input('enter the value of n = ')

j = input('enter the value of j = ')

 n = -i:1:i

u1 = (n>=0)

d1 = (n==0)

u2 = (n+j>=0)

u3 = (n-j>=0)

e1 = cos(2*pi*n)

e2 = cos(2*pi*(-n))

'addition x1=u1+d1'

x1 = u1+d1

'multiplication x1=u1*d1'

x2 = u1.*d1

'shifting x1=u2-u3'

x3 = u2-u3

'folding x1=-u1'

x4 = (-n>=0)

'shifting x1=u1+d1'

x3 = u2-u3

subplot(3,3,1)

stem(n,u1)

title(' u1 ')

subplot(3,3,2)

stem(n,d1)

title(' d1 ')

subplot(3,3,3)

stem(n,u2)

title(' u2 ')

subplot(3,3,4)

stem(u3)

title('u3')

subplot(3,3,5)

stem(n,x1)

title('addition x1 = u1+d1 ')

subplot(3,3,6)

stem(n,x2)

title('multiplication x1 = u1*d1 ')

subplot(3,3,7)

stem(n,x3)

title('shifting x1 = u2-u3 ')

subplot(3,3,8)

stem(n,x4)

title('folding x1 = -u1 ')

if e1==e2

display('function is even')

else

     display('function is odd')

end

Q.8 Plot each signal x[n] compare with the original signal. -10≥n≥10

a. x[n] = u[n+4] – u[n-4] + 2[n+6] – [n-3]                 y[n] = x[-n-4]

clc;

clear all;

close all;

 n = -10:1:10

u1 = (n+4>=0);

u2 = (n-4>=0);

d1 = 2*(n+6==0);

d2 = (n-3==0);

 m = (-n-4);

 x = u1-u2+d1-d2;

subplot(1,2,1);

stem(n,x);

subplot(1,2,2);

stem(m,x);

b. x[n] = u[n+4] – u[n-4] + 2[n+6] – [n-3]                 y[n] = x[2n+4]

clc;

clear all;

close all;

n=-10:1:10

u1 = (n+4>=0);

u2 = (n-4>=0);

d1 = 2*(n+6==0);

d2 = (n-3==0);

 m = (2*n)+4;

 x = u1-u2+d1-d2;

subplot(1,2,1);

stem(n,x);

subplot(1,2,2);

stem(m,x);