For sinusoidal peak-finding, spectral interpolation via zero-padding
gets us closer to the true maximum of the main lobe when we simply
take the maximum-magnitude FFT-bin as our estimate.
The examples in Fig.2.5 show how zero-padding helps in
clarifying the true peak of the sampled window transform. With enough
zero-padding, even very simple interpolation methods, such as
quadratic polynomial interpolation, will give accurate peak estimates.
ideal interpolation in the frequency domain as a result of zero
padding in the time domain.
Another illustration of zero-padding appears in
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