Chapter 8
Using LTE-FDD Signal Analyzer
220
JD700B Series User’s Guide
3
Do one of the following:
To
Select
Trace Legend
Clear current data and display with new
measurements
Clear Write
W
Display the input signal’s maximum response only
(unlimited or for a certain amount of time)
Max Hold
M
Display the input signal’s minimum response only
(unlimited or for a certain amount of time)
Min Hold
m
Capture the selected trace and compare traces
Capture
C
Load a saved trace
More (1/2) > Load
L
Hide the displayed trace
Trace View > Off
F
Remove all the traces and initialize the trace
settings
More (1/2) > Trace
Clear All
NOTE
For the
Max Hold
and
Min Hold
, your instrument compares newly acquired data with the
active trace and displays larger maximum values or smaller minimum values on the
screen. You can set it to
Unlimited
to hold and view maximum or minimum data or
specify a certain amount of time up to 60 seconds by using numeric keys or rotary knob.
4
Optional
. Select
More (1/2) > Trace Info
, 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.
5
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 and power spectral density (PSD) of the
signal in the LTE channel bandwidth.
Setting measure setup
After configuring test parameters as described in the “Configuring test parameters” on page 214, you can
continue your measurement.
Procedure
1
Press the
MEASURE SETUP
hot key.
2
Press the
Bandwidth
soft key.
3
Select the nominal channel bandwidth to be measured, from the choices:
1.4 MHz
,
3 MHz
,
5 MHz
,
10 MHz
,
15 MHz
, and
20 MHz
.