JDS Uniphase CellAdvisor JD780A Series, Руководство пользователя

Страница: 341 / 592

JD780A Series Analyzers
Using CDMA Signal Analyzer
341
4.
To select the detection option, press the More (1/2) > Detectors , and then do one of the
following:
To display Select
Random noise better than the peak without missing signals Normal
The highest value in each data point Peak
The root mean squared average power across the spectrum RMS
The lowest value in each data point Negative Peak
The center value in each data point Sample
5.
Optional . Press the More (1/2) > Trace Info soft key, and then select the trace number to view
the trace
’s parameter setting information stored at the time of the measurement or
None to hide
the information display.
6.
Optional. If you have the two traces T1 and T2, you can perform trace math. To view the power
difference between the traces, press the T1
– T2 -> T5
or T2
– T1 -> T6
soft key.
The result is overlaid on the screen along with the second Y-axis.
Conducting RF measurements
Channel power
The Channel Power measurement is a common test used in the wireless industry to measure the total
transmitted power of a radio within a defined frequency channel. It acquires a number of points
representing the input signal in the time domain, transforms this information into the frequency domain
using Fast Fourier Transform (FFT), and then calculates the channel power. The effective resolution
bandwidth of the frequency domain trace is proportional to the number of points acquired for the FFT.
The channel power measurement identifies the total RF power, power spectral density (PSD) and peak
to average ratio (PAR) of the signal within the channel bandwidth (1.23 MHz for cdmaOne).
After configuring test parameters as described in the
“Configuring test parameters” on page 334, your
measurement result is displayed on the screen as like the following example, Figure 158.