4.2 Sampling rate reduction (binary decimation)
54
Acqiris SA230E User's Manual
4.2 Sampling rate reduction (binary decimation)
A programmable binary decimation can be used to lower the sample rate by a ratio of 2, 4 or 8 (See
table below). Sampling rate reduction can be used in both digitizer and averager acquisition mode.
Decimation Ratio
Resulting sampling
rate
No
4 GS/s
2
2 GS/s
4
1 GS/s
8
500 MS/s
Table 4.1
- List of selectable sampling rates.
To enable decimation, user should set the sampling rate to required decimated sampling rate.
Decimation and bandwidth limitation
The table below provides the behavior when combining decimation and bandwidth limitation.
Decimation
factor
Effective
sampling
rate
Bandwidth
(typ-
ical)
bandwidth filter applied vs. Bandwidth limited (BWL)
None
BWL=700
MHz
BWL=200 MHz
BWL=20 MHz
1
4 GS/s
2 GHz
No filter
BWL=700
MHz
BWL=200 MHz
BWL=20 MHz
2
2 GS/s
920 MHz
Filter for decim-
ation factor = 2
BWL=700
MHz
BWL=200 MHz
BWL=20 MHz
4
1 GS/s
450 MHz
Filter for decim-
ation factor = 4
Filter for
decimation
factor = 4
BWL=200 MHz
BWL=20 MHz
8
500
MS/s
237 MHz
Filter for decim-
ation factor = 8
Filter for
decimation
factor = 8
BWL=200 MHz
BWL=20 MHz
Table 4.2
- Behavior and applied filter when combining decimation and bandwidth limitation.
