DSP  Task2  Basic Overview on DFT Properties

Properties of shorttime DFT  spectral leackage
 Generate sinus signal with parameters: f=50Hz, fs=200Hz, duration 1s .
 Evaluate shorttime DFT over this signal  ONE SPECTRAL LINE (function fft)  describe correctly axis (frequency)
 Evaluate shorttime DFT over the sequence with length wlen=190 vzorkù. Explain results.
 Evaluate shorttime DFT over the sequence with length wlen=190
vzorkù with application of weighting window (Hamming).
 Observe above points using other weighting windows (rectangular,
traingular, Hann, Hamming, Blackman)
 Observe lalso spectral characteristics of above mentioned windows
 Look at shorttime magnitude spectrum of the first 512 samples of
signal vm0.bin with weighting by above
mentioned windows.
 Properties of shorttime DFT  spectral resolution
 Generate sum of two sinusoidal signals with parameters: f1=400Hz,
f2=450Hz, fs=8 kHz, duration 1s .
 Try to find theoretically and then empirically minimal length of
the signal required for resolution of these two signals in
frequencydomain. Use also different weighting windows.
 Periodicity in DFT
 Evaluate spectrum (shorttime DFT) of one period of voiced vowel in speech signal vm0per.bin
 Observe, how the spectrum is changed in the case of adding zeros to the sequence.
 Observe, how the spectrum is changed in the case of the repetition of this period 2x, 3x, 4x.
 Observe, how the spectrum is changed in the case of 4times repetition of the period and for the window length 480, 479, 470, 460, 450.
 Observe the periodicity in real signal (real part of voiced vowel) vm0.bin, use window length approx. 200  500.
 Estimate the basic period for signals vf5.bin a vm5.bin
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This page was created Thu Oct 26 09:56:01 CEST 2000