Spectrum of windowed version of original continuous signal

1. What is windowing in spectral analysis?
2. What is phase spectrum of a signal?
3. How does windowing reduce spectral leakage?
4. What is the spectrum of a sampled signal?

What is windowing in spectral analysis?

Use smoothing windows to improve the spectral characteristics of a sampled signal. When performing Fourier or spectral analysis on finite-length data, you can use smoothing windows to minimize the discontinuities of truncated waveforms, thus reducing spectral leakage.

What is phase spectrum of a signal?

The phase spectrum specifies the phase of signal components as a function of. component frequency. This phase is measured with respect to a cosine reference.

How does windowing reduce spectral leakage?

Spectral leakage is caused by discontinuities in the original, noninteger number of periods in a signal and can be improved using windowing. Windowing reduces the amplitude of the discontinuities at the boundaries of each finite sequence acquired by the digitizer.

What is the spectrum of a sampled signal?

The sampled signal has a spectrum that is periodic at the sampling frequency (20 Hz) and has an even symmetry about 0.0 Hz, as well as symmetry about the sampling frequency, f_s. Since the sampled spectrum is periodic, it goes on forever and only a portion of it can be shown.