Agilent Technologies ENA Series User Manual page 345

Effect of frequency sweep range on response resolution
Figure 9-3 shows an example when measuring the same cable while changing the sweep
span. When measured in a narrower sweep range, the overlap between two peaks is larger
than when measured in a wider sweep range. By performing measurement in a wider
sweep range, adjacent peaks can be clearly separated, which means that the response
resolution is smaller.
Figure 9-4 Effect of frequency sweep range on resolution
The sweep range affects the width of the impulse signal and the rise time of the step signal.
The width of the impulse signal and the rise time of the step signal are inversely
proportional to the sweep range. Therefore, the wider the sweep range is, the shorter these
times are.
The resolution is equal to the width defined at the point of 50% of the impulse signal or the
rise time defined at the points of 10% and 90% of the step signal. (Figure 9-5)
Figure 9-5 Definitions of impulse width and step rise time
Chapter 9
Analysis in Time Domain (Option 010)
Transformation to time domain
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