JDS Uniphase CellAdvisor JD780A Series, Руководство пользователя

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JD780A Series Analyzers
162
Using WCDMA/HSPA+ Signal Analyzer
5 MHz, as per the 3GPP WCDMA technical specifications) and the power spectral density (PSD) in
dBm/Hz.
After configuring test parameters as described in the
“Configuring test parameters” on page 155, your
measurement result is displayed on the screen as like the following example, Figure 58.
Figure 58 Channel power measurement with WCDMA/HSPA+ 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 167 for more
information.
Occupied bandwidth
The 3GPP specifications require the occupied bandwidth (OBW) of a transmitted WCDMA signal to be
less than 5 MHz, where occupied bandwidth is defined as the bandwidth containing 99% of the total
channel power. In this measurement, the total power of the displayed span is measured. Then the
power is measured inward from the right and left extremes until 0.5% of the power is accounted for
each of the upper and lower part of the span and the calculated difference is the occupied bandwidth.
The spectrum shape
of a WCDMA signal can give a useful qualitative insight into the transmitter’s
operation. Any distortion to the spectrum shape might be an indication of degradation of the
transmitter's performance.
After configuring test parameters as described in the
“Configuring test parameters” on page 155, your
measurement result is displayed on the screen as like the following example, Figure 59.