Keysight Technologies N9340B User Manual page 109

Spectrum Emission Mask (SEM)
Spectrum Emission Mask measurement includes the
in-band and out-of-band spurious emissions. As it
applies to W-CDMA (3GPP), this is the power contained
in a specified frequency bandwidth at certain offsets
relative to the total carrier power. It may also be
expressed as a ratio of power spectral densities between
the carrier and the specified offset frequency band. For
WLAN, the reference power is taken as the peak PSD in
the signal, and all offset results are also the peak PSD in
that offset as opposed to the integrated power.
Avg Number
Key access: [MEAS] > {More} > {SEM} > {Avg Number}
Press Avg Number (On) to specify the number of
measurement averages used when calculating the
measurement result. The average will be displayed at
the end of each sweep.
Meas Type
Key access: [MEAS] > {More} > {SEM} > {Meas Type}
Displays a menu where you can select a measurement
reference type, Total Pwr Ref or PSD Ref. When Total Pwr
Ref is selected, the power in the carrier is used as the
reference in computing the relative power values for the
offsets. When PSD Ref is selected, the mean power
spectral density of the carrier is used in computing the
relative power spectral density values for the offsets.
Ref Channel
accesses the softkeys that enable you to change the
reference channel settings:
• Chan Integ BW
Key access: [MEAS] > {SEM} > {Ref Channel}
Specifies the integration bandwidth used in
calculating the power in the main channel.
Key Reference
MEAS
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