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System Noise and Synchronous Detection
106 Chapter Five
0 2 4 6 8 10 12 14 16
Figure 5.12 The 16-bit Walsh function waveforms.
SW
1
Amplitude V i
0.5 W1
W3
0
1 5
3 W7
7
-0.5
0 5 10 15 0 5 10 15 20 25 30
Frequency component i Time
Figure 5.13 Walsh frequency spectrum of a sine Figure 5.14 Original sine wave and the
wave. three Walsh functions used in its approx-
imation. The stepped response is just
the sum of the 1st, 3rd, and 7th individ-
ual Walsh functions with optimum
amplitudes.
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