Measurement Method For A Cdma System - Agilent Technologies ESA-E Series User And Programming Manual

Making Modulation Analysis Measurements
The Modulation Analysis Personality

Measurement Method for a CDMA System

Consider making an EVM measurement on a CDMA system.
You can only make an EVM measurement intrusively. When you
perform the measurement, a carrier channel with a single pilot channel
are the only allowed active channels. No other traffic channels or
paging channels may be present.
The intrusive method takes the measurement directly from the RF
output port of the transceiver, as shown in
If you take the measurement directly from the RF output port of the
CAUTION
transceiver, ensure that the power level at the RF input of the spectrum
analyzer does not exceed the damage level of 30 dBm.
Because you disconnect the antenna from the transceiver and disrupt
the transmission signal, this cannot be considered a non-intrusive test.
The transceiver will not be able to communicate with users on the
system.
You may also make a less intrusive test by connecting a directional
coupler to the RF output with the main arm connected to the antenna
and the coupled port connected to the spectrum analyzer, as shown in
Figure
Because only a pilot channel will be observed, the transceiver will not
be able to communicate with users on the system.
The time bases of the base station and the spectrum analyzer should be
NOTE
locked together. These are referred to as "10 MHz Ref In" or "Ext Ref In"
throughout the remainder of this document.
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4-2. You must ensure that only the pilot Walsh channel is active.
Figure 4-1.
Chapter 4