Real Filter Bank Example

Finally, Fig.10.40 shows the appearance of the octave filter bank for real signals. In this case, bands are constructed between dc and half the sampling rate, and conjugate symmetry is used to automatically construct the desired bands between half the sampling rate and the sampling rate. The band allocation algorithm therefore needs no modification for the real-signal case.

Figure: Channel-frequency-response overlay for a real-signal octave filter bank, designed using a length 127 Dolph-Chebyshev window and length 256 FFT size (no downsampling). Compare the complex-signal filter bank in Fig.10.38.
\includegraphics[width=0.8\twidth]{eps/impulse-cheb127h-rect128x-N256-real-qdcells}


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