Keysight P9241, Руководство программиста SCPI

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:FUNCtion<m> Commands
17
Keysight P9241/42/43A Oscilloscopes SCPI Programmer's Guide 375
• SQUare
• SQRT — Square root
• ABSolute — Absolute Value
• LOG — Common Logarithm
• LN — Natural Logarithm
• EXP — Exponential (e
x
)
• TEN — Base 10 exponential (10
x
)
Transforms operate on a single analog channel source or on lower math
functions.
• Filters:
• LOWPass — Low pass filter — The FREQuency:LOWPass command sets the
-3 dB cutoff frequency.
• HIGHpass — High pass filter — The FREQuency:HIGHpass command sets the
-3 dB cutoff frequency.
• AVERage — Averaged value — The AVERage:COUNt command specifies the
number of averages.
Unlike acquisition averaging, the math averaging operator can be used to
average the data on a single analog input channel or math function.
If acquisition averaging is also used, the analog input channel data is
averaged and the math function averages it again. You can use both types of
averaging to get a certain number of averages on all waveforms and an
increased number of averages on a particular waveform.
Averages are calculated using a "decaying average" approximation, where:
next_average = current_a (new_data - current_average)/N
Where N starts at 1 for the first acquisition and increments for each
following acquisition until it reaches the selected number of averages, where
it holds.
• SMOoth — Smoothing — The resulting math waveform is the selected source
with a normalized rectangular (boxcar) FIR filter applied.
The boxcar filter is a moving average of adjacent waveform points, where
the number of adjacent points is specified by the SMOoth:POINts command.
You can choose an odd number of points, from 3 to 999.
The smoothing operator limits the bandwidth of the source waveform. The
smoothing operator can be used, for example, to smooth measurement
trend waveforms.
• ENVelope — Envelope — The resulting math waveform is the amplitude
envelope for an amplitude modulated (AM) input signal.