Keysight N5244/45AS Option H85, Руководство пользователя и сервисное руководство

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N5245-90002 User’s and Service Guide 31
N5244/45AS Option H85
Example: Making High Power Measurements With Option H85
14.Estimate the maximum amount of gain that could be provided by the DUT, and as a result,
the maximum amount of power that could be received by Test Port 2 when the DUT is in
compression. For example; if a DUT with a maximum gain of +10 dB receives an input of 
+10 dBm, the maximum amount of power that could be received by Test Port 2 is +20 dBm.
An isolator or attenuator may be require depending on the amount of power at Test Port 2.
For Port 2 isolators and attenuator connections, an isolator is place between the CPLR THRU
and SOURCE OUT as shown in Figure 27 .
Figure 27 Isolators and Attenuator Connections
15.Calculate the amount of attenuation needed between the analyzer's coupler and receivers,
so that you do not exceed the optimum receiver power level of –12 dBm.
It will be necessary to take the following into consideration:
• Receiver A will be coupled to the analyzer RF path that could receive power
reflections as high as +10 dBm.
• Receiver B will be coupled to the analyzer RF path that could receive a maximum of
+20 dBm from the DUT.
• Analyzer coupler loss is –13 dB.
• The optimum receiver power level is –12 dBm.
With the previous points in mind, the amount of attenuation can be calculated from the
following equations:
Fix Attenuator
Isolator
In Out
Fix Attenuator
Booster Amplifier
RF
INPUT
RF
OUTPUT
Coupler
Arm
20 dB
Coupler
Main
Coupler
Output
Fix
Attenuator
CPLR ARM
RCVR A IN
SOURCE OUT
SOURCE OUT
RCVR R1 IN
CPLR THRU
CPLR THRU
CPLR ARM
RCVR B IN
Receiver Attenuator A 10 dBm 13 dBm 12 dBm –
 
– – + = Attenuator A 10 dBm + =
Receiver Attenuator B 20 dBm 13 dBm 12 dBm –
 
– – + = Attenuator B 20 dBm + =