MATLAB Programs

GENERATION OF SIMPLE SIGNALS



%GENERATION OF SIMPLE SIGNALS

clc;

clear all;

close all;

%Unit Impulse Signal

t=-2:2;

y=[zeros(1,2),1, zeros(1,2)];

subplot(221);

stem(t,y);

xlabel('Time Index');

ylabel('Amplitude');

%Unit Step Sequence

n=input('Enter the
length of step sequence N = ');

t=0:n-1;

y1=ones(1,n);

subplot(222);

stem(t,y1);

xlabel('Time Index');

ylabel('Amplitude');

%Ramp Sequence

n1=input('Enter the length of ramp sequence N = ');

t=0:n1;

subplot(223);

stem(t,t);

xlabel('Time Index');

ylabel('Amplitude');

n2=input('Enter the
length of exponential sequence N = ');

t=0:n2;

a=input('Enter the
value of a = ');

y2=exp(a*t);

subplot(224);

stem(t,y2);

xlabel('Time Index');

ylabel('Amplitude'); 

Enter the length of step sequence N = 8

Enter the length of ramp sequence N = 8

Enter the length of exponential sequence N = 8

Enter the value of a = -1

OUTPUT

 

AM GENERATION WITH DOUBLE SIDE BAND (DSB) AND SUPPRESSED CARRIER

%AM Wave DSB with carrier

clc;

clear all;

close all;

fc=input('Enter the carrier signal frequency in hz,fc = ');

fm=input('Enter the modulating signal frequency in hz,fm = ');

m=input('Modulation index,m= ');

n=0:0.001:1;

c=sin(2*pi*fc*n);%carrier signal

M=sin(2*pi*fm*n);% modulating signal

y=(1+m*M).*c;%AM signal

subplot(2,1,1);

plot(n,y);

ylabel('amplitude');

xlabel('time index');

%AM
with suppressed carrier

n=0:0.001:1;

c=sin(2*pi*fc*n);%carrier signal

M=sin(2*pi*fm*n);% modulating signal

y=M.*c;

subplot(2,1,2);

plot(n,y);

axis([0 1 -2 2]);

ylabel('amplitude');

xlabel('time index');

Enter the carrier signal frequency in Hz, fc = 50 

Enter the modulating signal frequency in Hz, fm = 5 

Modulating index, m = 0.5

OUTPUT

LINEAR CONVOLUTION USING BUILT IN FUNCTION

%Linear Convolution using built-in function

clc;

clear all;

close all;

x=input('Enter the input sequence x[n] = ');

lx=input('Enter the starting time index of x[n] = ');

h=input('Enter the input sequence h[n] = ');

lh=input('Enter the starting time index of h[n] = ');

y= conv(x,h);

n=lx+lh:length(y)+lx+lh-1;

stem(n,y);

ylabel('Amplitude');

xlabel('Time Index');

title('Linear Convolution');

Enter the input sequence x[n] = [1 2 3 4]

Enter the starting time index of x[n] = -2

Enter the input sequence h[n] = [3 3 4]

Enter the starting time index of h[n] = -1

SQUARE WAVE FROM SINUSOIDAL HARMONICS

%SQUARE WAVE FROM SINUSOIDAL HARMONICS

clc;

clear all;

close all;

y=0;

h=input('No of harmonics = ');

f=input('enter the frequency =');

t=0:0.005:1/f

for i=1:2:h

y= y+sin(i*2*pi*f*t)/i;

plot(t,y);

pause;

hold on;

end


No of harmonics = 20
enter the frequency =0.5

 
IMPULSE RESPONSE OF LTI SYSTEM 

%Impulse Response of LTI System

clc;

clear all;

close all;

N=input('Enter the required length of the impulse response, N = ');

b=input('Enter coeffecients of x[n], b = ')

a=input('Enter coeffecients of y[n], a = ')

x=[1, zeros(1, N-1)];

y=filter(b,a,x);

n=0:N-1;

stem(n,y);

xlabel('Time Index n');

ylabel('Amplitude');

title('Impulse response of the system');

Enter the required length of the impulse response, N = 40
Enter coeffecients of x[n], b = [ -0.8 -0.44 -0.36 -0.22]

b =

   -0.8000   -0.4400   -0.3600   -0.2200

Enter coeffecients of y[n], a = [1 0.7 -0.45 -0.6]

a =

    1.0000    0.7000   -0.4500   -0.6000