What's new with FieldFox handheld spectrum analyzers?

Easily capture signals with FieldFox handheld spectrum analyzers

Interference Hunting

Identify and locate the source of unwanted emitters and interfering signals with real-time spectrum analysis.

Control you spectrum by pairing Keysight Spectrum Management Software with FieldFox handheld spectrum analyzers

Keysight Spectrum Monitoring Software (KSMS)

Control your spectrum, measure utilization, and identify interference, all in a single platform.

Hunt down elusive signals with FieldFox handheld spectrum analyzers

Fox Hunt

Join this 9-part video series on hunting down elusive signals with the FieldFox handheld spectrum analyzer.

Woman in keysight lab with FieldFox handheld spectrum analyzer and EMF antenna

5G Field Testing Course

Explore path loss and electromagnetic field (EMF) measurements and 5G NR over-the-air (OTA) demodulation with RTSA.

Industry's most integrated handheld spectrum analyzer

Keysight's FieldFox portable spectrum analyzers come equipped to handle routine maintenance, in-depth troubleshooting, and anything in between. Choose the software-enabled Keysight FieldFox configuration that best meets your needs.

  • Get coverage up to 54 GHz with precision comparable to benchtop results.
  • Make 5G field test a reality with wide analysis bandwidth up to 120 MHz.
  • Capture small, interfering signals with wideband, real-time analysis.
  • Perform measurements with one of the lightest instruments in the industry — 30% lighter than other handheld analyzers.
  • Configure FieldFox handheld spectrum analyzer as a cable and antenna analyzer (CAT), vector network analyzer (VNA), spectrum analyzer, or an all-in-one combination analyzer.

Never miss a signal

  • Easily capture and demodulate intermittent, beam sweeping technologies used in 5G and radar systems.
  • Detect small signals once masked by stronger signals with RTSA.
  • Measure signals as narrow as 5.52 µs with 100% Probability of Intercept (POI) and full amplitude accuracy.
  • Accelerate communications system development by quickly switching to over-the-air (OTA) measurements.

FieldFox RF analyzer software

Offering 25+ license-key activated software applications.

Interference Analyzer and Spectogram software screenshot

Spectrum Analysis

  • Real-time spectrum analyzer (RTSA)
  • Analog demodulation
  • Interference hunting
  • IQ analyzer
2 port s parameters software screenshot

Cable and Antenna Testing (CAT)

  • Vector network analysis (VNA)
  • 2 port S-parameters
  • TDR Cable Measurements
RTSA Interference hunting on FieldFox Handheld Analyzer

5G / LTE Field Testing

  • EMF Measurements
  • Over-the-air (OTA) testing
  • Channel Scanner
  • Wideband Analysis
Pulse Measurement with USB Peak Power Sensor software

Power Measurements

  • USB Power Sensor Measurements
  • Built-in Power Meter
  • Pulse Measurements
  • Peak Power Sensor
Indoor and Outdoor Mapping for data collection


  • Remote Control
  • GPS Receiver
  • Indoor/Outdoor Mapping
  • DC Bias Variable Voltage Source

Related use cases

How to Test a Satellite Transceiver with DVB-S2X Signals

How to Test a Satellite Transceiver with DVB-S2X Signals

Testing satellite transceivers with DVB-S2X signals for conformance and interoperability requires signal analysis under real-world conditions. Learn how to use signal creation and analysis to test your satellite transceiver.
How to Optimize SNR

How to Optimize SNR

Predicting RF product performance requires a deep understanding of noise sources. Learn how to measure and manage the noise floor of a device to achieve the optimal signal-to-noise ratio (SNR) and what instrument to use for different signals.
How to Measure RF Phase Noise

How to Measure RF Phase Noise

Measuring RF and microwave frequency phase noise requires a dedicated phase noise instrument. Learn how to deploy three techniques to measure RF phase noise: direct spectrum, phase detector, and two-channel cross-correlation.
How to Test Satellite Receivers for Wideband Interfering Signals

How to Test Satellite Receivers for Wideband Interfering Signals

Monitoring and detecting wideband interfering signals in satellite receivers, requires a signal analyzer capable of performing wideband real-time spectrum analysis (RTSA) to ensure even short-duration signals are captured. Learn how to measure wideband RTSA and provide gapless analysis bandwidths to see, capture, and understand the most elusive signals, even with a very low probability of intercept.
How to Characterize the Signal Quality of a Transmission Channel

How to Characterize the Signal Quality of a Transmission Channel

Measuring the phase distortion variations to ensure signal quality in transmission channels requires repeatable channel response measurements such as group delay and other characteristics of multi-channel signals. Learn how to measure accurate signal quality and make repeatable channel response measurements targeting wideband components testing in satellite communications.
How to Measure Noise Figure Using Y-Factor Method

How to Measure Noise Figure Using Y-Factor Method

Measuring noise figure requires characterizing a receiver and its ability to detect weak incoming signals in the presence of self-generated noise. Learn how to use the Y-factor method to conduct noise figure and gain measurement.

Never sacrifice capability or portability

Field testing modern communications networks puts new demands on your equipment and requires trade-offs between capabilities and portability. With over 25 software-enabled measurement capabilities in one portable, battery-powered unit, FieldFox handheld spectrum analyzer is the most capable handheld analyzer in the industry. Stay ahead of changing measurement requirements by upgrading your handheld analyzer in the field with convenient, user-installable license keys.

portable spectrum analyzer used in field testing

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FieldFox handheld spectrum analyzers: frequently asked questions

A handheld spectrum analyzer is a compact, portable instrument for measuring and displaying the frequency spectrum of signals. Similar to the benchtop spectrum analyzer, the core function is to visually represent the strength of signals across a range of frequencies. Other advanced features include signal demodulation, real-time spectrum analysis, and integrated geolocation.

Spectrum analysis primarily measures the frequency, power, and noise of a signal. All of these are essential measurements in the field, where lugging a benchtop analyzer would be difficult. Handheld analyzers are portable, rugged, and lightweight. They are built to last in harsh conditions and overcome sun glare. Bring the solutions out in the field with you and never compromise capability or portability.

Yes, using real-time spectrum analysis (RTSA) up to 50 GHz, FieldFox can capture interfering signals in real-time. With a dynamic density display and high Fast Fourier Transform (FFT) rate, the FieldFox displays gap-free data capture. For more information about FieldFox RTSA, check out our brochure: FieldFox Handheld Analyzers with Real-time Spectrum Analysis (RTSA).  

The key spectrum analyzer functions of FieldFox are over-the-air (OTA) measurements, real-time spectrum analysis (RTSA), electromagnetic field (EMF) measurements, analog demodulation, channel scanning, and noise figure analysis. 

Handheld spectrum analyzers are multi-purpose tools used for verifying and maintaining communication system performance. This includes troubleshooting RF networks, interference hunting, performing site surveys, and ensuring regulatory compliance. 

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