Product category:
Stand-Alone Instruments
News Release from: Rohde and Schwarz | Subject: Differential measurement for network analysers.
Edited by the Electronicstalk Editorial
Team on 28 March 2007
Network analyser does differential
measurements
A software option adds a true differential measurement mode up to 40GHz to an existing family of network analysers.
Rohde and Schwarz has introduced a software option that adds a true differential measurement mode up to 40GHz to the R and S ZVA and R and S ZVT network analysers It is thus possible for the first time to precisely characterise nonlinear balanced components, which are increasingly included in mobile phones
This article was originally published on Electronicstalk on 8 Sep 2004 at 8.00am (UK)
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Up to now, network analysers were only able to mathematically calculate the differential parameters from unbalanced single measurements.
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Up to now, the characteristics were calculated by overlaying several unbalanced stimulus states.
This approach is not equivalent to use under real conditions and can lead to deviating measurement results, in particular with DUTs in nonlinear operation.
Rohde and Schwarz now presents an enhancement for the network analysers of the R and S ZVA and R and S ZVT family which allows fully corrected measurements using true differential signals up to 40GHz.
In this true differential measurement, two internal generators generate signals of identical amplitude and 0deg and 180deg phase offset (phase deviation <1deg).
The network analyser resets the amplitude and phase relation at each test point and thus also takes into account fluctuations of the DUT's input reflection.
The measured differential wave quantities and thus also the mixed-mode S parameters are fully corrected of system errors.
The new option can be integrated into the instruments by means of a software update and requires no additional hardware for calibration or measurement.
It is easy to switch quickly between the virtual differential approach currently used and the new true differential mode.
For direct comparison of the measurement results, the two methods can be applied simultaneously.
In addition, it is possible to provide the DUT with a differential-mode or a common-mode stimulus and to measure the absolute output power in differential or common mode.
The amplitude or phase relation of the differential signal is variably adjustable.
It can also be swept, making it possible to simulate non-ideal real stimulus states.
The R and S ZVA -K6 true differential mode option for the R and S ZVA and R and S ZVT is now available from Rohde and Schwarz. Request a free brochure from Rohde and Schwarz ...
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