6-2
IM DLM3054-01EN
Acquisition mode (Mode)
Select from the following.
Normal Mode (Normal)
Displays waveforms without processing the sampled data.
Envelope Mode (Envelope)
The instrument determines the maximum and minimum values among the data sampled at 2.5 GS/s at the time
interval that is 2 times of the sampling period (the inverse of the sample rate) of the Normal mode setting and
displays the values as pairs to produce the waveform.
This mode is effective when you want to avoid aliasing, because the sample rate is essentially kept high
regardless of the time axis setting. It is also effective when you want to detect glitches (narrow pulse signals) or
when you want to display the envelope of a modulated signal. This mode can be used when the sample rate is
625 MS/s or less.
Envelope mode
Normal mode
If you set the acquisition mode to Envelope when the sample rate is set to 1.25 GS/s or higher, the instrument
actually operates in Normal mode. In envelope mode, [Envelope] appears in the upper right of the screen. If
envelope is in use in high resolution mode, [Env:Hi-Res] appears.
Averaging Mode (Average)
In Averaging mode, the instrument acquires waveforms numerous times, averages the same time points relative
to the trigger point, and displays averaged waveforms. Averaging mode is useful when you want to remove
random noise from waveforms.
You cannot use the history feature in Averaging mode.
The averaging method varies depending on the trigger mode.
• Auto, Auto Level, or Normal mode: Exponential averaging
• Single mode: Linear averaging
• N Single mode: Actually operates in Normal mode.
To average waveforms that have been acquired in N Single mode, set the acquisition mode to Normal, and
turn on history feature’s averaging.
6 Waveform Acquisition