R&S ZVB - Page 380

R&S
®
ZVA / R&S
®
ZVB / R&S
®
ZVT GUI Reference
Channel Menu
Operating Manual 1145.1084.12 – 30 365
Extensions
 The network analyzer provides two alternative measurement procedures for maximum flexibility
concerning the signal levels or maximum speed. See Sequential vs. Simultaneous measurement.
 For measurements on non-frequency-converting DUTs: To prevent excess input levels (especially
for analyzers without source attenuators), it is possible to loop an external attenuator in-between
the NWA source port and the input of the DUT. An external attenuator can also improve the match
at the DUT input. Proper noise figure calibration ensures that the gain and noise figure of the
external attenuator is compensated.
 Conversely, it is possible to use an external low-noise preamplifier in order to reduce the noise
figure of the NWA receiver and thus improve the measurement accuracy. The gain and noise
figure of the pre-amplifier is also compensated during the noise figure calibration. Refer to the
background information in section Noise Figure Calibration to learn more about the relationship
between receiver noise figure, preamplifier gain and measurement accuracy.
A suitable low-noise preamplifier (option R&S ZVAX-B203) is available in combination with the
Extension Unit, R&S ZVAX24.
 Options R&S ZVA-B16, Direct Generator and Receiver Access, improve (i.e. reduce) the noise
figure of the NWA source and receiver. On analyzers equipped with options R&S
ZVA<frequency>-B16, it is also possible to measure the noise figure using a single port. Connect
the NWA port connector to the DUT and route back the output signal to the MEAS IN connector of
option R&S ZVA<frequency>-B16. On a four-port analyzer, this allows you to measure four DUTs
in parallel.
 On four-port analyzers, it is possible to perform two noise figure measurements in parallel using
two different port combinations.
 Network analyzers with upper frequency limits in the microwave range have an enhanced
coupling attenuation below 1 GHz. This can impair the accuracy of the noise figure measurement.
Noise Figure Setup Guide
The Noise Figure Setup Guide gives access to all necessary steps of a noise figure measurement. The
dialog is similar to a wizard, however, everything is arranged in a single dialog. The panels numbered 1. to
7. suggest a meaningful order for the different steps. In some cases, it is possible to change the order or
skip a step entirely (e.g. a calibration may be skipped if a valid calibration for the test setup is already
available).
The buttons in the different panes open dialogs or wizards; all of them are also accessible from the menus
of the network analyzer. In general, it is advantageous though to open the dialogs from the setup guide,
because this will adjust some of the settings to the requirements of the noise figure measurement.