What's A Realtime Spectrum Analyzer?

Spectrum analyzers measure the magnitude of an input signal over a specified frequency range, displaying signal frequency, power, distortion, harmonics, etc. that are not easily available with time domain waveforms. Standard spectrum analyzers sweep a limited frequency band receiver over the range of the instrument, but this means that intermittent or frequency-hopping signals will be missed or incorrectly reported.  Realtime analyzers don’t have that limitation since they use overlapping FFTs to view the whole spectrum range at the same time.  Realtime techniques simplify spectrum monitoring to quickly capture, identify, and analyze complex RF environments containing frequency hopping signals, channel conflicts and spectrum interference.

What does “real-time” mean? It means the operating speed captures events "live" and not in a swept fashion. Real-time operation means all signal samples are processed continuously and gap-free.

Realtime spectrum analyzers are available in three form factors: benchtop, portable, and handheld.

Benchtop versions are useful for lab applications with easy access to AC power. Rigol benchtop RSAs can identify compliance problems with built in EMI test configurations and analysis capability.  

PC-based portable spectrum analyzers are useful for bench or field work. Optional battery-powered operation tallows the user to move freely outside, or install remotely for in-place spectrum monitoring. 

Handheld analyzers are lightweight with battery-powered operation to allow the user to move freely in outside environments.

Capture transient and short duration signals 
Find signals of interest
Analyze RF signals 

Rigol Benchtop RSA3000 and RSA5000 series.  

Siglent Benchtop RSAs

ThinkRF R5550 PC-basedRSAs

Aaronia Handheld Spectran5 RSAs