R&S NRP2 - Page 84

Instrument Functions
R&S
®
NRP2
66User Manual 1173.9157.02 ─ 03
"Burst Av"
The Burst Average mode is used to measure the average burst power
of pulsed signals. The acquisition interval is automatically derived from
the signal (see chapter 4.2.1.3, "Measuring the average power of burst
signals", on page 68).
SCPI command:
[SENSe<[1]..4>]:FUNCtion[:ON] on page 268
4.2.1.2 Continuous average-power measurements
The "Cont Av" mode is the preferred measurement method if the measurement is not to
be, or cannot be, synchronized with a specific signal event.
This is the only available measurement mode for thermal power sensors because they
are too slow for the other measurement modes.
► Select "Cont Av" in the "Mode..." dialog box opened via the "Sensor" menu.
Fig. 4-5: Mode dialog box / Cont Av
Aperture
Defines the aperture time (size of the acquisition interval). In the manual operating mode,
the sensor-specific default setting combined with active smoothing (see below) is usually
adequate. Another value, generally larger, is helpful if the result exhibits fluctuations due
to modulation. In particular with very low frequency modulation, we recommend that you
adjust the aperture time exactly to the modulation period, in order to obtain stable read-
ings:
Optimal aperture time
Smoothing
Off N x ( modulation period / 2)
On
N x ( modulation period * 2)
N = 1, 2, 3, …
I.e. the minimum theoretical measurement time can only be obtained with smoothing
turned off.
Data acquisition and parameters