October 17, 2011. The latest generation network analyzer from Rohde & Schwarz now also comes with four test ports and a second internal generator. The new four-port R&S ZNB models cover the frequency ranges from 9 kHz to 4.5 GHz or 8.5 GHz. With the new instrument, the company is targeting applications in the production and development of RF components with multiple ports.
Two internal signal sources and a frequency-converting mode enable comprehensive measurements on mixers or amplifiers. Using mixed-mode S-parameter measurements, the R&S ZNB fully characterizes even balanced DUTs such as SAW filters used in mobile phones. For balanced measurements, the network analyzer determines the mixed-mode S parameters without using external baluns. Extensive analysis functions make it possible to display the desired measured quantity directly on the screen in real time. External postprocessing is not necessary.
The four-port network analyzer can also be used to measure high-blocking duplex filters, couplers, splitters, or isolators. They need only be connected once to the R&S ZNB. In addition to mixer conversion loss and impedance matching, users can determine virtually any secondary measured quantities, including crosstalk between ports. Thanks to the R&S ZNB’s second internal source, intermodulation measurements on amplifiers can be configured with a single, compact instrument.
All R&S ZNB models feature dynamic range of more than 140 dB, low trace noise, IF bandwidths of 1 Hz to 10 MHz, and an output power of up to +13 dBm, which can be lowered electronically by 100 dB. The R&S ZNB offers a sweep time of 4 ms for 401 points.
The instruments feature a large touch screen (12.1″ or 30.1 cm) to facilitate configuration and analysis. All instrument functions are accessible in no more than three operating steps via the soft panel. A toolbar and drag and drop functionality allow users to configure the instruments quickly. They can switch between measurement setups at the touch of a finger. Traces and measurement channels can be configured and combined as desired. Users can therefore display results in a clear and straightforward manner even for complex measurements.