ESS210B
Prof. Jin-Yi Yu
The Weighting Effect of Square Window
qThe square window smooth the true spectrum.
qThe degree of the smoothing is determined by the window length
(T).
qThe shorter the window length, the stronger the smoothing will
be.
qIn addition to the smoothing effect, data window also cause “spectral leakage”.
qThis leakage will introduce spurious oscillations at higher and lower frequencies and are out of phase
with the true oscillation.
Response Function of Square Window
Spectral Leakage
(From Hartmann 2003)