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FIGURE 27.25 Sampling rate conversion with multistage oversampling.<br />

FIGURE 27.26 Sampling rate conversion in frequency domain: (a) interpolation, (b) decimation.<br />

• Frequency-domain approach based on: first, a blockwise DFT; second, on respective spectrum<br />

modification in each block—a throw-in of zero spectral samples in the middle of the DFT spectrum<br />

for interpolation or cutting out of some of spectral samples in the middle of the DFT spectrum<br />

for decimation (cf., Fig. 27.26); and third, the backward blockwise IDFT transformation (cf., the<br />

interpft function in the MATLAB environment [30]).<br />

© 2002 by CRC Press LLC<br />

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