ETS-Lindgren 5411 GTEM! Test Cell - Manual (Page 31)

Measured GTEM! Performance
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5.0 Measured GTEM! Performance
Several different measurable quantities exist that illustrate the performance of a
Gigahertz Transverse Electromagnetic (GTEM!™) Cell. Typical measurements
are discussed in this section.
GTEM! Performance Qualification – VSWR
The Voltage Standing Wave Radio (VSWR) of a terminated transmission line is a
fundamental performance parameter. The value of the VSWR reading is a
measure of mismatch; therefore, it completely defines the capability of a
GTEM! to transfer power to or from interconnected 50-ohm RF test equipment.
The VSWR is a qualifying measurement for GTEM! cells. Most GTEM! cells are
pre-assembled at the factory and the VSWR verified at that time. Following is the
VSWR of a typical Model 5407 measured with an HP8753C vector network
analyzer.
T
YPICAL
VSWR M
EASUREMENT
– M
ODEL
5407
GTEM! Electromagnetic Field Response
E-F
IELD
F
REQUENCY
R
ESPONSE
The E-field frequency response is defined as the measurement of the electric
field strength at a specific point in the GTEM! measured as a function of
frequency and normalized to a constant forward input power.