The R&S®FSWP offers an internal signal source (R&S®FSWP-B64 option) for measuring additive phase noise. Amplifiers, doublers, splitters and other two‑port components cause additive phase noise even though they do not generate a signal. When developing high‑end radar applications, for instance, it is vital to know how much phase noise these individual components as well as the local oscillator are adding to the signal. Only then is it possible to develop extremely low‑noise transmitters.
Previously, complex setups with a high-quality external signal source, splitters and the appropriate phase shifters were required to measure this parameter. The measurement was highly vulnerable to electromagnetic disturbances and vibration. With the R&S®FSWP, users simply connect the internal signal source to the input of the DUT and the DUT output back to the R&S®FSWP. The additive phase noise of the DUT is then available at the push of a button.
Enhanced sensitivity through cross‑correlationThe R&S®FSWP uses cross‑correlation for this operating mode as well. There are two paths for converting the measured signal to the baseband to suppress the additive phase noise of the internal frequency converters. This enables the analyzer to deliver significantly better sensitivity than PLL based measurements and allows users to develop even lower‑noise transmitters, for example to improve the range and time resolution of radar systems.
Additive phase noise on pulsed signalsEquipped with the R&S®FSWP-K4 option, the R&S®FSWP can measure additive phase noise on pulsed signals.
To characterize and optimize components for a radar transmitter, for example, these components have to be tested under real-world conditions using pulsed signals. Amplifiers operating in pulsed mode behave much differently than in continuous wave mode. The R&S®FSWP delivers this measurement – previously possible only with extremely complex test setups – at the push of a button.
