Tektronix RSA2200A, User Manual

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Product Overview
RSA2203A & RSA2208A User Manual
1- 3
Real-Time Analysis
This section explains real-time analysis with the comparison of conventional
swept spectrum analyzer and real-time spectrum analyzer.
Figure 1--1 is a block diagram of the conventional swept spectrum analyzer.
There are two RF input signals in this example. The RF signal is converted to IF
(intermediate frequency) by the swept local oscillator. IF output goes through a
bandpass filter, where resolution of the spectrum analyzer is defined.
Local
oscillator
RF input
Mixer
Resolution
filter
Detector Display
F
F
Figure 1- 1: Concept of the swept spectrum analyzer
The filter is swept from F
start
to F
stop
. See Figure 1--2. Only signals within the
filter bandwidth are observed at one point in time. Signal A is detected first and
then signal B is detected and displayed.
NOTE
. An intermittent signal, such as a burst phenomenon, will not be detected
unless it is present at the exact moment that the filter is being swept past it.
Sweep
F
start
F
stop
A B
Figure 1- 2: Sweep of resolution filter
Conventional Swept
Spectrum Analyzer