R3267 Series Spectrum Analyzer Operation Manual (Vol.1)
2.3.6 Measuring Adjacent Channel Leakage Power (ACP)
2-87
2.3.6
Measuring Adjacent Channel Leakage Power (ACP)
One of the most important items to be measured of the digital modulating signal, which is used in the Per-
sonal Handy Phone and so on, is the adjacent channel leakage power (ACP).
In this section, the following two modes are explained: PDC digital modulating signal measurements in
Full screen mode using the Root Nyquist filter, the adjacent (or the second adjacent) channel leakage pow-
er measurements for PHS in Separate screen mode.
Full screen mode:
Calculates the total power using the data on the entire screen, calculates the chan-
nel leakage power of the upper and lower adjacent channels by integration to the
specified bandwidth (BS), and calculates the ratio of the previously obtained val-
ues. The time required for taking measurements using this mode is shorter than the
other mode since all necessary data is collected in a single sweep. In addition, a
graphic function, which permits you to display the power at a point by integrating
the leakage power over the specified bandwidth with respect to this point, is avail-
able.
Separate screen mode: Automatically sets the frequency span to the specified bandwidth, measures Car-
rier wave power (on the upper screen), measures the adjacent channel leakage
powers (on the lower screens) (or the second adjacent leakage powers on the lower
screens), and calculates the ratios separately. Using this mode, a higher accuracy
is obtained when the channel spacing is large enough in relation to the specified
bandwidth.
CAUTION:
1.
Set the values to meet the following unless otherwise specified.
Detection mode: Sample
Trace Average function: OFF
2.
The VBW must meet the following.
VBW
≥≥≥≥
RBW
2.3.6.1 Full Screen Mode
This section describes how to measure PDC digital modulating signal using the Root Nyquist Filter in
Full screen mode.
Measurement conditions: The unit used in this measurement must output a PDC signal with a frequency
of 917.950 MHz and a level of +10 dBm.
Use appropriate parameter values to make the measurements shown below.
ACP Measurement Setup
1.
Connect the unit under test as shown in Figure 2-95.
RBW
≤
40
1
×
Specified bandwidth
