## Saturday, 16 November 2013

### Study and Implementation of Discrete Time Signal and Continuous Time Signal using Stem and Plot Command Respectively.

AIM: Study and Implementation of Plot and Stem Command.
THEORY:
1. For ‘STEM’ Command:
A discrete time signal has a value defined only at discrete points in time in these signals the independent variables takes only a discrete set of integer values.
e.g. Attendance of students Vs date (time)
Representation of DT sequence:

Unit Step:

A discrete unit step is denoted as u(n) and is mathematically defined as
The DT unit step signal is shown is fig,
Unit Impulse:
The discrete time unit impulse is denoted as and is mathematically defined as
The DT unit impulse signal is shown in fig.
Sinusoidal:
The discrete time sinusoidal is denoted as  and is mathematically defined as
The DT unit sine signal is shown in fig.
Unit Ramp:
The discrete time unit ramp is denoted as  and is mathematically defined as
The DT unit ramp signal is shown in fig.
Exponential Growing:
The discrete time Exponential growing is denoted as  and is defined as
The DT Exponential growing signal is shown in fig.
Exponential Decaying:
The discrete time Exponential decaying is denoted as  and is defined as
The DT Exponential decaying signal is shown in fig.
2. For ‘PLOT’ Command:
Similarly like Stem command plot command having same concept. Instead of stem just use Plot command for getting continuous signals.
Syntax for plot:
Plot(x coordinate values, y coordinate values).

PORCEDURE:
1.    Define samples on x axis.
2.    Define amplitude on y axis according to each and every signal.
3.    Using stem function just discretize x axis and use plot signal for getting continuous signal.
4.    Give xlabel, ylabel and title.

1. Plot Command Implementation:
Program:
% Implementation of Plot Command
%sine Wave
x=0:0.001:10;
y=sin(x);
subplot(3,2,1)
plot(x,y);grid on
title('Sine Wave')

%cos wave
y1=cos(x);
subplot(3,2,2)
plot(x,y1);grid on
title('Cosine Wave')

%Exponential Growing Wave
y2=exp(x);
subplot(3,2,3)
plot(x,y2);grid on
title('Exponential Growing Wave')

%Exponential Decaying Wave
y3=exp(-x);
subplot(3,2,4)
plot(x,y3);grid on
title('Exponential Decaying Wave')

%Exponential Decaying Wave
y4=x;
subplot(3,2,5)
plot(x,y4);grid on
title('Ramp Signal')

2. Stem Command Implementation:
Program:
% Implementation of Discrete signals
% Sine wave
x=0:1:20;
y=sin(x);
subplot(3,2,1)
stem(x,y);grid on
title('Sine Wave')

%cos wave
y1=cos(x);
subplot(3,2,2)
stem(x,y1);grid on
title('Cosine Wave')

%Exponential Growing Wave
y2=exp(x);
subplot(3,2,3)
stem(x,y2);grid on
title('Exponential Growing Wave')

%Exponential Decaying Wave
y3=exp(-x);
subplot(3,2,4)
stem(x,y3);grid on
title('Exponential Decaying Wave')

%Exponential Decaying Wave
y4=x;
subplot(3,2,5)
stem(x,y4);grid on
title('Ramp Signal')