Agilent/Keysight N9935B

The Keysight N9935B FieldFox is a handheld microwave network and spectrum analyzer engineered for field characterization of RF and microwave devices and systems. It delivers immediate spectrum analysis with ±0.3 dB measurement accuracy - no warm-up required - and captures intermittent signals across a 120 MHz gap-free real-time bandwidth. The instrument performs cable and antenna analysis, radar pulse profiling, over-the-air measurements for 5G NR and LTE, and RF signal monitoring via I/Q data capture.

Built-in GPS/GNSS provides geolocation and timestamping. Weighing 3.4 kg, it integrates a power meter and supports optional tracking generator, pre-amplifier, and extended range transmission analysis (ERTA) capabilities.

Technical Specifications

• Frequency Range: 9 kHz to 9 GHz (usable down to 5 kHz)


• Spectrum Analyzer Accuracy: ±0.3 dB (without warm-up)


• Real-Time Bandwidth: 120 MHz gap-free


• Output Power (with tracking generator option): Up to 1 dBm


• Test Port Connector: Type-N (f)


• Weight: 3.4 kg (7.4 lb)


• Dimensions: 11.5 in (H) × 7.4 in (W) × 3.2 in (L)

Key Features

• Spectrum analysis with immediate, accurate measurements


• Cable and antenna characterization


• I/Q data capture for RF signal monitoring and analysis


• 5G NR and LTE over-the-air measurement capability


• Radar pulse profile characterization


• Integrated power meter


• Optional tracking generator for extended measurement range


• Optional pre-amplifier for enhanced sensitivity


• Integrated GPS/GNSS for geolocation and timestamping


• Interference analysis with spectrogram display (Option 236)


• USB power sensor measurements versus frequency (Option N9935BU-208)


• Extended Range Transmission Analysis support (Option N9935BU-209)


• Optional remote control (N9935BU-030)

Typical Applications

• Field-based RF and microwave device testing


• 5G NR and LTE signal characterization


• Radar pulse analysis and profiling


• Interference identification and monitoring


• Cable and antenna validation

Compatibility & Integration

• Compatible with standard HP/Agilent/Keysight mechanical calibration kits and all Keysight USB ECal modules


• Supports 89600 VSA software for signal recording and evaluation


• LAN connectivity for data transfer


• Includes AC/DC adapter, rechargeable Li-ion battery, soft carrying case with backpack and shoulder straps, and quick reference guide