Ceyear 4992A, User Manual

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Chapter VII Performance feature test
103
the T/R port of the tested device.
7) Set the cursor of the spectrum analyzer to the maximum peak. If the power reading is
43dBm±3dB and the spectrum analyzer is not subject to IF overload, the upper limit of the power
measurement range of the spectrum analyzer is more than or equal to +43dBm.
8) The lower limit of the power measurement range of the spectrum analyzer is the displayed
average noise level. Connect the T/R port to the matching load and change the spectrum analyzer
setting as follows.
Reference: -40dBm
sweep width: 10kHz
resolution bandwidth: 10Hz
Average: ON
Averaging times:16
When the trace becomes stable, test the peak value of the trace with the cursor and check whether
the displayed average noise level of this port is no more than -50dBm. Record the above results in
the test record table A.21.
9) Test the indicators of the ANT port. As shown in the figure, connect the output signal of the
signal source to the ANT port of the tested device.
Set the output of the signal source as follows.
Frequency: 499MHz;
Power: -25 dBm
10) Open the spectrum analyzer window by pressing the [Measurement] hard key and setting the
instrument menu. Set it as follows.
Port: ANT
Center frequency: 499MHz
Reference: 0dBm
sweep width: 1MHz
resolution bandwidth: 10kHz
Other parameters: auto.
11) Set the cursor of the spectrum analyzer to the maximum peak. If the power reading is
-10dBm±3dB and the spectrum analyzer is not subject to IF overload, the upper limit of the power
measurement range of the spectrum analyzer is more than or equal to -10dBm.
12) The lower limit of the power measurement range of the spectrum analyzer is the displayed
average noise level. Apply the matching load on the ANT port, and change the spectrum analyzer
setting as follows.
Reference: -80dBm
sweep width: 10kHz
resolution bandwidth: 10Hz
Average: ON
Averaging times:16
When the trace becomes stable, test the peak value of the trace with the cursor and check whether
the displayed average noise level of this port is no more than -110dBm. Record the above results
in the test record table A.21.
E. Accuracy of amplitude measurement