JDS Uniphase CellAdvisor JD780A Series, User Manual

Page: 274 / 592

JD780A Series Analyzers
274
Using LTE
– TDD Signal Analyzer
Measurement example
Figure 122 Occupied bandwidth measurement with LTE - TDD signal analyzer
NOTE
You can use the LIMIT hot key to analyze your measurements with the user-definable
limit and Pass/Fail indication. See
“Setting limit for RF tests” on page 279 for more
information.
Spectrum emission mask (SEM)
The Spectrum Emission Mask (SEM) measurement required by 3GPP specifications encompasses
different power limits and different measurement bandwidths (resolution bandwidths) at various
frequency offsets. It may be expressed as a ratio of power spectral densities between the carrier and
the specified offset frequency band. It provides useful figures-of-merit for the spectral re-growth and
emissions produced by components and circuit blocks, without the rigor of performing a full SEM
measurement.
The SEM measures spurious signal levels in up to five pairs of offset or region frequencies and relates
them to the carrier power.
Setting measure setup
After configuring test parameters as described in the
“Configuring test parameters” on page 265, you
can continue your measurement.
Procedure
1.
Press the MEASURE SETUP hot key.
2.
To set the nominal channel bandwidth to be measured, complete the following steps:
a. Press the Bandwidth soft key.
b. Select the bandwidth option: 1.4 MHz , 3 MHz , 5 MHz , 10 MHz , 15 MHz , or 20 MHz .
3.
To select the mask type, complete the following steps: