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R&S FSH
Spectrum Analyzer Mode
Performing Spectrum Measurements
Operating Manual 1309.6275.12 - 14
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If the DUT features some sort of trigger equipment, you can also use an external
trigger to trigger measurements.
M
Connect the DUT trigger output to the R&S FSH trigger input.
M
Press the SWEEP key.
M
Press the "Trigger" softkey.
M
Select either the "External Rise" or "External Fall" menu item (rising or falling
edge).
The R&S FSH activates the trigger and shows the results of the measurement.
It may be that the burst is not completely visible on the display. To correct that and
make the whole burst visible, you can set a trigger delay.
M
Press the "Trigger" softkey.
M
Select the "Trigger Delay" menu item.
The R&S FSH opens an input field to define the trigger delay.
M
Adjust the trigger delay until the burst is visible inside the vertical lines that show
the measurement range.
2.1.4 Measuring the Adjacent Channel Leakage Ratio (ACLR)
The Adjacent Channel Leakage Ratio (ACLR) measurement is a method to measure
the power over more than one transmission channel and also evaluate the power of
the adjacent (or alternate) channels of the transmission channel. The ACLR performs
measurements according to a specific channel configuration, e.g. a particular radio
communications standard.
M
Press the MEAS key.
M
Press the "Meas Mode" softkey.
The R&S FSH opens the measurement menu.
M
Select the "ACLR" menu item.
The R&S FSH starts to measure the adjacent channel leakage ratio.
In principle, the ACLR measurement works like the channel power measurement in
that it determines the spectrum within the channel using a resolution bandwidth that is
small compared to the channel bandwidth. In addition to the channel bandwidth, the
ACLR measurement is also defined by the channel spacing, the bandwidth of adjacent
channels and the adjacent channel spacing. The R&S FSH offers measurements on up
to 12 carrier channels and 12 adjacent channels to either side of the carrier. When
measuring more than one carrier or adjacent channels, the R&S FSH shows the
powers of each channel in a list below the marker list. The channel itself is marked by
red (transmission channels) or green (adjacent channels) vertical lines.