Isolation (Crosstalk, Exf And Exr) - Agilent Technologies 8719ET Service Manual

Error Terms
Error Term Descriptions

Isolation (Crosstalk, EXF and EXR)

These are the uncorrected forward and reverse isolation error terms that represent
leakage between the test ports and the signal paths. The isolation error terms are
characterized by measuring transmission (S21, S12) with loads attached to both ports
during the measurement calibration. Since these terms are low in magnitude, they are
usually noisy (not very repeatable).
Significant System Components. Loose cable connections or leakage between
components in the lower box are the most likely cause of isolation problems. The transfer
switch, bias tees, couplers, and samplers are the most susceptible components.
Affected Measurements. Isolation errors affect transmission measurements, primarily
where the measured signal level is very low. An example is a transmission measurement
where the insertion loss of the DUT is large.
Figure 11-4 Typical EXF/EXR with 3 kHz Bandwidth
11-14
8719ET/20ET/22ET
8719ES/20ES/22ES
RF Network Analyzers
Service Guide