R&S FSPN phase noise analyser and VCO tester

For high-speed, real-time phase noise measurements using sources that require high stability in demanding applications, the R&S FSPN from Rohde & Schwarz provides a combination of good sensitivity, performance and ease of use. The phase noise analyser and VCO tester has been designed for production and design engineers who characterise sources such as synthesisers, VCOs, OCXOs and DROs. Providing high sensitivity and measurement speed, it is suitable for demanding phase noise and VCO analysis in development and production.

The device comes in two models: one covers the frequency range from 1 MHz to 8 GHz and the other from 1 MHz to 26.5 GHz, addressing radar and satellite applications in the C band, X band, Ku band and the complete K band. Catering to the measurement challenges in these fields, the product includes features such as low noise internal local oscillators coupled with real-time cross correlation engines for increased measurement sensitivity.

Cross-correlation sensitivity gains can be viewed in real time in result traces, allowing users to adjust the trade-off between measurement speed and sensitivity to meet their application requirements. Users in production need just a few correlations to measure high-quality oscillators, synthesisers or VCOs with high throughput. By increasing the number of correlations, users in R&D can characterise the most sensitive commercially available synthesisers and oscillators. Simultaneous device frequency and phase settling times can be measured with up to 8 GHz of real-time analysis bandwidth. To investigate oscillator long-term frequency stability, the device calculates the Allan variance in the time domain at fixed intervals and uses phase noise measurements to apply cross-correlations and suppress spurs.

The product is equipped with three ultralow-noise DC sources to supply and sweep VCOs. The built-in VCO characterisation measurement mode analyses VCO characteristics such as frequency, sensitivity, RF power or current draw versus tuning voltage. For a more in-depth view of the device under test, the spot-noise versus tune measurement mode combines a sweep with ultralow-noise DC sources plus fast phase noise measurements. VCO harmonics can also be measured versus tuning voltage without an additional spectrum analyser.