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Window Design Techniques 327<br />

of attenuation. These window functions bear the names of the people<br />

who first proposed them. Although these window functions can also be<br />

analyzed similar to the rectangular window, we present only their results.<br />

7.3.2 BARTLETT WINDOW<br />

Since the Gibbs phenomenon results from the fact that the rectangular<br />

window has a sudden transition from 0 to 1 (or 1 to 0), Bartlett suggested<br />

a more gradual transition in the form of a triangular window, which is<br />

given by<br />

⎧<br />

2n<br />

M − 1 , 0 ≤ n ≤ M − 1<br />

2<br />

⎪⎨<br />

w(n) =<br />

2 − 2n<br />

M − 1 , M − 1<br />

(7.25)<br />

≤ n ≤ M − 1<br />

2<br />

⎪⎩<br />

0, otherwise<br />

This window and its frequency-domain responses are shown in Figure 7.11.<br />

Bartlett Window : M=45<br />

Amplitude Response in dB<br />

1<br />

0<br />

w(n)<br />

Decibels<br />

27<br />

0<br />

0 22 45<br />

n<br />

Amplitude Response<br />

60<br />

1 0 1<br />

frequency in π units<br />

Accumulated Amplitude Response<br />

22<br />

0<br />

Width=(6.1)*pi/M<br />

Wr<br />

Decibels<br />

26<br />

0<br />

−1 0 1<br />

frequency in π units<br />

60<br />

−1 1<br />

frequency in π units<br />

FIGURE 7.11 Bartlett window: M =45<br />

Copyright 2010 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s).<br />

Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it.

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