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Applications
R&S
®
RTA4000
178
User Manual 1335.7898.02 ─ 08
If the menu does not open, tap twice: Once to enable FFT, and next to open the
menu.
Source
Selects the channel for which the captured data is analyzed with FFT. You can select
one of the active input channels, math or reference waveforms.
Remote command:
FFT Window
Windowing helps minimize the discontinuities at the end of the measured signal inter-
val and thus reduces the effect of spectral leakage, increasing the frequency resolu-
tion.
The R&S
RTA4000 provides various window functions to suit different input signals.
Each window function has specific characteristics, including some advantages and
some trade-offs. Consider these characteristics to find the optimum solution for the
measurement task.
"Hanning"
The Hanning window is bell shaped. Unlike the Hamming window, its
value is zero at the borders of the measuring interval. Thus, the noise
level within the spectrum is reduced and the width of the spectral
lines enlarges.
Use this window to measure amplitudes of a periodical signal pre-
cisely.
"Hamming"
The Hamming window is bell shaped. Its value is not zero at the bor-
ders of the measuring interval. Thus, the noise level inside the spec-
trum is higher than Hanning or Blackman, but smaller than the rectan-
gular window. The width of the spectral lines is thinner than the other
bell-shaped functions.
Use this window to measure amplitudes of a periodical signal pre-
cisely.
FFT analysis