Signal Hound SM200A - Page 37

Appendix A: Typical Performance | Sweep Speed (Fast)
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- RBW, lower RBWs require larger FFT sizes which increase the overall USB throughput
and dwell times at each IF frequency.
- PC performance (less so when using the API directly), the Spike software performs trace
averaging/maxholding as well as persistence and waterfall displays which can all
contribute to lower sweep times. Generally for desktop processors we do not see slow
down associated with this, but low power laptop processors can be the bottleneck for
sweep speed.
- Center frequency, frequencies below 600MHz will slow the sweep down because the
smaller IF bandpass filters at those frequencies prevent 160MHz of IF acquisition.
Additionally, moving the center frequency while maintaining the same span might change
which IF frequencies are used and might change how many are used.
The SM435B has similar sweep speeds below 24 GHz, but may be slower than 1 THz/s for certain
spans above 24 GHz.
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 500 1000 1500 2000
Sweep Speed (THz/s)
Span (MHz)
Sweep Speed vs. Span (i7-4700, Avg Detector)
30k RBW
100k RBW
300k RBW