Rohde & Schwarz R&S UPP, User Manual

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Instrument Functions
R&S
®
UPP
404 User Manual 1411.1055.32 ─ 10
"Critical
Bands" The audio range is divided into "critical bands" according to the Bark
scale. The band limits are on the Bark scale and the center frequen-
cies are 0.5 Bark above the lower band limit in each case.
Due to the division into "critical bands" the low frequency bands are
wider than in the case of the comparable third octave analysis, for
which reason both the required FFT size and the measurement time
are smaller.
Remote command:
SENSe[1]:FUNCtion:MMODe
on page 753
Meas Time
For selecting the measurement time.
The minimum measurement time is the same as the sampling time of the FFT and is
therefore defined by the FFT size used. When a longer measurement time is selected,
a greater number of FFTs is performed and averaged, reducing both the update rate
and fluctuations in the measured values.
In turn the required FFT size is dependent on the sampling rate or the analog band-
width and the width of the narrowest subband, that is, on the measurement mode and
the lower band limit.
"Auto" This sets the minimum possible measurement time.
This setting is recommended for the purpose of measuring independ-
ently of the lower band limit and measurement mode, and always
using the highest measurement speed.
"Value " A numerical value for the measurement time is entered in the next
parameter field.
The measurement time entered is rounded to an integer multiple of
the minimum measurement time and thus implicitly defines the num-
ber of averages.
This setting is recommended for the purpose of reducing the update
rate and fluctuations in the measured values.
Remote command:
SENSe[1]:FUNCtion:APERture:MODE
on page 753
SENSe[1]:VOLTage:APERture
on page 754
Filter
Activating a digital filter in the test channel. Up to two user-defined or weighting filters
can be looped into the test channel:
Frequency Band Analysis