Agilent Technologies 33120A, Руководство пользователя

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Leakage error is caused when the waveform record does not include an
integer number of cycles of the fundamental frequency. Power from the
fundamental frequency, and its harmonics, is transferred to spectral
components of the rectangular sampling function. Instead of the
expected narrow spectral lines, leakage can cause significant spreading
around the desired spectral peaks. You can reduce leakage errors by
adjusting the window length to include an integer number of cycles or
by including more cycles within the window to reduce the residual
end-point transient size. Some signals are composed of discrete,
non-harmonically related frequencies. Since these signals are
non-repetitive, all frequency components cannot be harmonically related
to the window length. You should be careful in these situations to
minimize end-point discontinuities and spectral leakage.
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Chapter 7 Tutorial
Creating Arbitrary Waveforms
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