
Agilent X-Series Signal Generators SCPI Command Reference
29
Basic Function Commands
Digital Modulation Subsystem—N5172B/82B ([:SOURce])
the 160 MHz baseband bandwidth, at the current frequency.
When this feature is on, arbitrary frequency switching while the baseband is on will take up to an
additional 3.3ms (typical) to 6.8ms the first time that frequency is specified. After that, switching to
that frequency will take up to an additional 1.3ms. Up to 1024 unique frequencies can be cached
before the oldest cache will be forgotten. If a frequency sweep is activated, then the calculation and
caching will occur up front for the first 1024 unique frequencies, and all further unique frequencies
will have the characteristics of arbitrary frequency switching.
If the I/Q correction optimized path is set to Ext I/Q Output, then only the baseband corrections are
applied and the frequency switching is unaffected.
This correction is convolved with the ACP internal I/Q channel optimization filter and the
equalization filter, if they are active. The resulting filter is truncated to 256 taps.
Example
:DM:INT:CHAN:CORR ON
The preceding example enables the internal channel correction calibration.
Key Entry
Int Channel Correction Off On
:DM:INTernal:CHANnel:OPTimization
Supported
N5172B/82B
[:SOURce]:DM:INTernal:CHANnel:OPTimization EVM|ACP
[:SOURce]:DM:INTernal:CHANnel:OPTimization?
This command selects between optimizing the internal I/Q channel for EVM (in channel performance)
at the expense of ACP (out of channel performance) or optimizing for ACP at the expense of EVM.
EVM is an 80% Nyquist filter (160 MHz wide) with a wide transition band. When an equalization
filter is active, this filter is not active.
ACP is an 80% Nyquist filter (160 MHz wide) with a narrow transition band, thus reducing images for
wide- band signals. This filter will be convolved with the active equalization filter, the result of which
will be truncated to the center 256 taps.
*RST
EVM
Key Entry
Optimize Int I/Q Channel EVM ACP
:DM:INTernal:EQUalization:FILTer:SELect
Supported
N5172B/82B
[:SOURce]:DM:INTernal:EQUalization:FILTer:SELect "Filter"
[:SOURce]:DM:INTernal:EQUalization:FILTer:SELect?
This command selects the FIR file to use as the equalization filter. Equalization filters are typically
complex and must have an oversample ratio of 1. The filter must not have more than 256 taps (512
coefficients for a complex filter). The equalization filter operates at 200 MHz, so all equalization
filters must be resampled to 200 MHz if they are sampled at some other rate.
*RST
No file selected
Key Entry
Select Filter