11. Crosstalk And System Dynamic Range; Description - Keysight E5071C ENA Service Manual

Performance Test

11. CROSSTALK AND SYSTEM DYNAMIC RANGE

11. CROSSTALK AND SYSTEM DYNAMIC RANGE

Description

This test checks the crosstalk between test ports of the E5071C, and the
system dynamic range for the receiver ports of the E5071C. The crosstalk is
tested by performing the "through measurements" with two test ports
connected together, and the short-ended "isolation measurements" with the
test ports terminated with "Short" devices. A "through" calibration is performed
to have the "through measurements" data as the reference to which the
"isolation measurements" data is compared. With segment sweep points for a
specified frequency range, a swept measurement with the short-ended test
ports is repeated 16 times and the measurement data is averaged. The worst
crosstalk value is determined from the peak value of the average data.
For crosstalk, average 16 times what is measured through minimum IFBW, and
take the effect for noise away as much as possible. For dynamic range, deduct
for crosstalk value and calculate noise value. To measure through worst case,
connect the short termination to the port.
The short-ended isolation measurement is all that is needed to compute the
crosstalk. The through needed for System Dynamic Range will not be
measured during the Crosstalk measurement.
The system dynamic range is tested by performing an "Isolation" measurement
16 times with segment sweep points for specified frequency ranges (after the
response and isolation calibrations are performed) and calculating the RMS
deviation value from the 16 measurement data for each sweep frequency point.
The maximum RMS deviation value in each frequency range is extracted to
determine the system dynamic range performance.
This test will utilize the "Isolation" measurement deduced from crosstalk, but
will not measure "Through" measurement in order to shorten testing time. The
"Through" measurement will be included in the measurement uncertainty
analysis (major contributor is transmission tracking).
Two Channels are required in order to run the Crosstalk and System
Dynamic Range test. If only one channel is allocated, then the first
connection check will fail even when properly connected, and the test will
not run correctly.
Keysight E5071C ENA Network Analyzers 53