Parameter Interactions; Data Size Considerations; Resolution Bandwidth - Agilent Technologies 89410A Operator's Manual

Video Demodulation Concepts (Opt. AYH)

Parameter interactions

Changing one parameter may necessitate changes in other parameters to achieve
the desired measurement. The following topics may help you optimize your
measurements and explain the reasons for changes made automatically by the
analyzer.

Data size considerations

Maximum data size for measured and reference IQ data is generally determined by
++
max time pts which is user selectable, 64-2048 (up to 4096 samples with
extended RAM option UFG or UTH). A given measurement will generally use all
available memory as defined by max time pts:
max time pts≥ result length × points ⁄ symbol

Resolution bandwidth

Resolution bandwidth in video demodulation is determined automatically by the
analyzer, and cannot be set independently. Resolution bandwidth is determined by
the time record length in the same manner as in Vector mode (see Fundamental
Measurement Interactions):
RBW = WBW ⁄ T
where RBW = resolution bandwidth
T = time record length
WBW = window bandwidth
However, in Video Demodulation the time record length is determined as follows:
T ≈ Result Length (in symbols) ⁄ Symbol Rate
++ See [ max time points ] under [ System Utility ], [ memory usage ], [ configure meas memory ]
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