Specifications

ZVx Selftest
1043.0009.50 4.3 E-3
4.3 Function Description of the Complete Instrument
The members of the ZVR/ZVC families are vector network analyzers with three measurement channels
(ZVRE, ZVRL, ZVCE) or four measurement channels (ZVR, ZVC).
• A Test Set with SWR bridges, power splitters, RF switches and level detectors makes for separation
of the test signal, feeding-in and switchover of the generator signal and measurement of the
generator level.
• Generation of the test signal is accomplished in three modules, i.e. Synthesizer, Source and
Output Stage.
• Signal processing is performed by several RF, IF and evaluation modules, a Measurement
Control Unit, which carries out both signal evaluation and control of generator, reception and
evaluation unit, and a processor unit, consisting of a 586 PC, I/O board with interfaces and a
graphics card.
The instruments can be upgraded to meet future requirements by retrofitting options in the analog,
digital and software area.
4.3.1 Description of the Analog Modules
4.3.1.1 Test Set
The test set mainly consists of an electronic switch, two SWR bridges or couplers (ZVC, ZVCE) with
integrated signal attenuator and level detector as well as the test set interface which permits control of
the test set by means of the MCU (Measurement Control Unit).
Signal path
The amplified RF signal coming from the output stage is taken via the electronic
switch and, depending on the measurement mode (switch position), via one of
the two power splitters into the associated SWR bridge (coupler) and thus to the
input or output of the DUT connected to the network analyzer. The second path
of the respective power splitter feeds the associated reference channel.
The SWR bridges (couplers) separate the signal reflected by the DUT from the
signal fed into the DUT (reflection measurement) or transmit the signal coming
out of the DUT (transmission measurement) to one of the reception channels.
Extensions/
options
• Up to four independent attenuators can be integrated in the test set. They
permit to attenuate both the RF signals fed to the DUT (i.e. test ports port1 or
port2) and those transmitted from the DUT in steps of 10 dB up to max. 70
dB.
• The option External Measurements enables additional test applications that
avoid the internal SWR bridges (couplers).
• The option Reference Mixer Ports permits to route the RF reference signal for
port1 via an RF relay and an externally connected reference mixer to the front
end in the case of frequency-converting measurements. This allows for phase
and group delay measurements during frequency conversion.
Instrument versions
The function of the test sets of models ZVRE, ZVRE and ZVRL mainly
corresponds to that of the test set described above. A main difference is the
lower number of reception channels: Whereas the ZVR and ZVC are equipped
with four channels, the ZVRE, ZVCE and ZVRL feature only three channels. Like
the ZVR and ZVC, the ZVRE and ZVCE are bidirectional network analyzers, the
test sets of which contain two SWR bridges (couplers) and an RF switch. Thus,
all four S-parameters of a DUT can be measured in both directions.