Keysight Technologies X-Series, Руководство по программированию

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216 Keysight CXG, EXG, and MXG X-Series Signal Generators Programming Guide
Creating and Downloading Waveform Files
Waveform Structure
I/Q File
The I/Q file contains the interleaved I and Q data points (signed 16–bit integers
for each I and Q data point). Each I/Q point equals one waveform point. The
signal generator stores the I/Q data in the waveform directory.
Waveform
A waveform consists of samples. When you select a waveform for playback, the
signal generator loads settings from the file header. When the ARB is on, it
creates the waveform samples from the data in the marker and I/Q (waveform)
files. The file header, while required, does not affect the number of bytes that
compose a waveform sample. One sample contains five bytes:
To create a waveform, the signal generator requires a minimum of 60 samples.
To help minimize signal imperfections, use an even number of samples (for
information on waveform continuity, see “Waveform Phase Continuity” on
page 217 ). When you store waveforms, the signal generator saves changes to
the waveform file, marker file, and file header.
If you download I/Q data using a file name that currently resides on the
signal generator, it also overwrites the existing marker file setting all bits
to zero and the file header setting all parameters to unspecified.
I/Q Data Marker Data
1 Waveform Sample
+
=
2 bytes I
(16 bits) 2 bytes Q
(16 bits)
1byte (8 bits)
Bits 4–7 reserved—Bits 0–3 set
5 bytes