WavePro 7 Zi and Zi-A Oscilloscopes
69
WP7Zi-GSM-E RevB
4.
Touch inside the
Select Segment
field and enter a segment number,
using the pop-up keypad or touch the arrow buttons to scroll
through segment times.
RIS Sampling Mode - For Higher Sampling Rates
RIS (Random Interleaved Sampling) is an acquisition technique that allows
effective sampling rates higher than the maximum single-shot sampling
rate. It is used on repetitive waveforms with a stable trigger. The
maximum effective RIS sampling rate is achieved by making multiple
single-shot acquisitions at maximum real-time sample rate. The bins thus
acquired are positioned approximately 5 ps (200 GS/s) apart. The process
of acquiring these bins and satisfying the time constraint is a random one.
The relative time between ADC sampling instants and the event trigger
provides the necessary variation.
The instrument requires multiple triggers to complete an acquisition. The
number depends on the sample rate: the higher the sample rate, the more
triggers are required. It then interleaves these segments (in the following
graphic) to provide a waveform covering a time interval that is a multiple
of the maximum single-shot sampling rate. However, the real-time interval
over which the instrument collects the waveform data is much longer, and
depends on the trigger rate and the amount of interleaving required.
Note
: RIS mode is not available when the oscilloscope is operating in
fixed sample
or DBI 25 - 45 GHz) modes as covered in
Smart Memory
(available in the online help files) and
Combining Channels
topics,
respectively.
