Stanford Research Systems SR785, Руководство по эксплуатации и программированию

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Curve Fit Menu 4-161
SR785 Dynamic Signal Analyzer
Curve Fit Menu
The Curve Fit Menu calculates best fit curve parameters from a measured frequency
response function. Synthesis of user entered curve parameters is also provided.
Start Fit
When start fit is pressed the analyzer begins the curve fitting process. The SR785 will
determine a fit to the data in the active display, which must be part of the FFT or swept-
sine measurement group. When determining the fit, the analyzer uses the fit region and
weighting specified in the fit setup submenu.
After the fit is determined, the fit parameters are placed in curve Table 1.The curve in
table 1 is then synthesized into whichever trace is specified by the table. The non-active
display is taken off-line, and the trace with the fit data is displayed.
The fit parameters include the frequency scaling specified in curve table 1. For instance,
if the frequency scaling is set to 1000, a pole at 1 kHz will show up as a term (s-1) in the
pole/zero display.
Command: EFIT d
Synthesize Table (1 and 2)
Synthesizes the curve in table 1 or 2 into a trace. The frequency range and resolution
over which the synthesis is performed is determined by the active display, which must be
part of the FFT or swept-sine measurement group.
When the synthesis is complete the data in the active display is replaced by the trace
containing the synthesis.