Keysight Technologies N5171B EXG, Руководство пользователя

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Keysight EXG and MXG X-Series Signal Generators User’s Guide 237
Basic Digital Operation (Option 653/655/656/657)
Scaling a Waveform
How Scaling Eliminates DAC Over–Range Errors
Scaling reduces the amplitude of the baseband
waveform while maintaining its basic shape and
characteristics, such as peak–to–average power
ratio. If the fast–rising baseband waveform is
scaled enough to allow an adequate margin for
the interpolator filter overshoot, the interpolator
filter can calculate sample points that include the
ripple effect and eliminate the over–range error
(see the figure at the right).
Although scaling maintains the basic shape of the
waveform, excessive scaling can compromise
waveform integrity. For example, if the bit
resolution becomes too low the waveform
becomes corrupted with quantization noise. To
achieve maximum accuracy and optimize
dynamic range, scale the waveform no more than
is required to remove the DAC over–range error.
Optimum scaling varies with waveform content.