324 Keysight N9038A MXE Service Guide
Analog & Digital IF
A2 Analog I.F. Assembly Description
Anti-Alias Filter and Final Amplifier
The anti-alias filters attenuate unwanted out-of-band noise and distortion
products. The first anti-alias filter is centered at 22.5 MHz and is 25 MHz
wide.
The signal can bypass the second anti-alias filter when the analyzer utilizes
either the IQ Analyzer swept, or wide-band demod.
The through path is selected when the image filter is in the 25 MHz mode
(for IQ Analyzer swept and wide-band demod)
In all other cases the signal will pass through the second 12 MHz anti-alias
filter.
The step gain block provides an additional switchable 10 dB gain to
overcome the ADC noise floor and provide an additional 2 dB of sensitivity.
Burst Carrier Trigger
The Burst Carrier Trigger detector provides a binary signal to be used as a
trigger based on the presence of an RF input signal or not. The variable gain
amplifiers drive a detector and its output drives a comparator which
generates the trigger signal.
Overall A2 Analog IF Assembly Resolution Bandwidth
In Spectrum Analyzer mode in the Swept SA measurement, the different filter
paths are selected by the instrument when different resolution bandwidths are
selected. Table 10-2 outlines what signal paths are used for what resolution
bandwidths. The 25 MHz filter path is not used in the Spectrum Analyzer
mode. It is used in the IQ Analyzer mode.
Table 10-2 A2 Analog IF Filter Path Selection
Filter Path Resolution Bandwidth Range
12 MHz 430 kHz to 8 MHz
1 MHz 180 kHz to 390 kHz
300 kHz 30 kHz to 160 kHz
75 kHz 4.3 kHz to 27 kHz
10 kHz 1 Hz to 3.9 kHz
To Next Page
Loading...
Need help?
General
