Rohde & Schwarz FSQ8 20Hz – 8GHz Spectrum Analyzer

The Rohde & Schwarz FSQ8 is a dual-function signal and spectrum analyzer spanning 20 Hz to 8 GHz, engineered for wireless communications, aerospace and defense, and RF measurement applications requiring simultaneous spectrum and signal integrity analysis. The instrument delivers exceptional RF performance through low phase noise, high dynamic range, and calibrated accuracy across its operating band. With selectable resolution bandwidth from 1 Hz to 10 MHz and sweep times as fast as 2.5 ms in frequency domain, the FSQ8 supports both development and production environments where stringent measurement tolerances are non-negotiable.

Technical Specifications

Frequency Coverage: 20 Hz to 8 GHz (DC coupled); 1 MHz to 8 GHz (AC coupled) Resolution Bandwidth: 1 Hz to 10 MHz selectable Sweep Performance: 2.5 ms frequency domain; 1 µs time domain Measurement Points: 155 to 30,001 per trace Signal Analysis: 28 MHz standard; 120 MHz optional I/Q Memory: 16 Msample standard; expandable to 705 Msample Dynamic Range & Linearity:

• TOI: +25 dBm typical


• 1 dB Compression Point: +13 dBm typical


• DANL (1 Hz RBW): -158 dBm @ 1 GHz; -154 dBm @ 7 GHz


• Display Linearity (0 dB to -70 dB): 0.1 dB


• Total Level Uncertainty (f < 3.6 GHz): 0.3 dB Phase Noise (SSB, 1 Hz): -160 dBc/Hz @ 10 MHz offset, 640 MHz carrier; -133 dBc/Hz @ 10 kHz offset ACLR: 77 dB (3GPP); 84 dB (3GPP with noise correction) IF Digitizer: 14-bit at 81.6 MHz (20.4 MHz IF); 14-bit at 326.4 MHz (Option FSQ-B72) I/Q Sample Rate: Programmable 10 kHz to 81.6 MHz in 0.1 Hz steps Reference: Internal OCXO (1 × 10⁻⁷ aging/year); optional high-stability unit (3 × 10⁻⁸); external 1 MHz to 20 MHz input

Key Features

• Preamplifier options (R&S FSU-B24, R&S FSU-B25) extend sensitivity to -173 dBm


• Spectral purity: -140 dBc typical @ 1 MHz offset


• Configurable trace detectors: Max Peak, Min


• Wide dynamic measurement capability from narrowband to wideband acquisition

Typical Applications

• Wireless transceiver characterization and validation


• Aerospace/defense signal intelligence and compliance testing


• Adjacent channel and intermodulation distortion analysis


• Phase noise and spectral emission measurement

Compatibility & Integration External reference clock input supports 1 MHz to 20 MHz sources in 1 Hz steps. Optional modules expand IF digitization rates and analysis bandwidth for specialized measurement protocols.