Rohde & Schwarz FSU43 20Hz – 43GHz Spectrum Analyzer

The Rohde & Schwarz FSU43 is a spectrum analyzer covering 20 Hz to 43 GHz, designed for demanding RF measurement and analysis across aerospace, defense, and communications sectors. It delivers exceptional dynamic range, low noise floor, and rapid measurement speed through a full suite of analysis functions including spectrum, modulation, and time-domain analysis. The FSU43 achieves a displayed average noise level of -158 dBm (1 Hz) and outstanding phase noise performance of -123 dBc at 10 kHz offset, enabling detection and characterization of weak signals close to thermal noise limits.

Technical Specifications

• Base unit: 20 Hz to 43 GHz


• Extended range to 110 GHz and above with optional external mixers (R&S FS-Z60/-Z75/-Z90/-Z110) Noise and Dynamic Performance:


• Displayed average noise level: -158 dBm (1 Hz); -152 dBm with preamp enabled


• Phase noise: -123 dBc (1 Hz) at 10 kHz offset


• Third-order intercept: +25 dBm typical


• Adjacent-channel power ratio: 77 dB ACLR (84 dB with noise correction)


• Measurement uncertainty: <0.3 dB total Resolution and Sweep Capabilities:


• Resolution bandwidth: 10 Hz to 50 MHz (standard filters); 1 Hz to 30 kHz (FFT); 39 channel filters (100 Hz to 5 MHz); EMI and RRC filters included


• Minimum sweep time: 2.5 ms standard; 1 µs in zero span


• Measurement rate: Up to 80 measurements/s in manual mode

Key Features

• Full detector complement for diverse signal types


• Gated sweep and IF power trigger included as standard


• Noise correction for weak signal measurements


• Modulation analysis, time-domain analysis, and spectral characterization


• TOI, adjacent-channel power (MC ACP), occupied bandwidth (OBW), and CCDF measurements

Measurement Options

• Noise figure and gain (R&S FS-K30)


• Phase noise analysis (R&S FS-K40)


• GSM/EDGE, Bluetooth, WCDMA/HSDPA/TD-SCDMA, and CDMA2000/1xEV firmware


• Scalar network analysis with optional tracking generator

Integration GPIB and LAN interfaces (R&S FSP-B16 option) enable remote control. External mixer support (R&S FSU-B21 option) with dedicated LO/IF ports extends measurement capability to millimeter-wave frequencies.