PRACTICAL MATLAB® FOR ENGINEERS PRACTICAL MATLAB

Time Domain Representation of Continuous and Discrete Signals 49

>> subplot(3, 1, 1);

>> plot(n, WHAM);

>> title(‘Hamming(31) window’);

>> ylabel(‘Amplitude’);xlabel(‘n’)

>> subplot(3, 1, 2);

>> plot(n, WHAN);

>> title(‘Hanning(31) window’);

>> ylabel(‘Amplitude’);xlabel(‘n’)

>> subplot(3, 1, 3);

>> plot(n, WBLAC);

>> title(‘Blackman(31) window’);

>> xlabel(‘n’);

>> ylabel(‘Amplitude’)

R.1.157 Observe that the Hamming, Hanning, and Blackman window models shown in

Figure 1.39 present similar shapes. They are plotted on the same graph for com-

parison purposes in Figure 1.40, given by script fi le compare_win.

MATLAB Solution

% Script file:compare _ win

% This file returns the plots of the

% HAMMING, HANNING and BLACKMAN windows

% using 31 points.

%*******************************

clc;clf;

n = -15:1:15;

Blackman (31) window

− 15 − 10 − 5 0 5 10

n

15

1

0.5

− 15 −^10 −^5051015

0

Hamming (31) window

Hanning (31) window

1

0.5

− 15

1

− 10 −^5051015

0

Amplitude

Amplitude

Amplitude n

n

0.5

0

FIGURE 1.39

Plots of the Hamming, Hanning, and Blackman windows of R.1.156.