Tektronix designs real-time spectrum analyzers (RTSA) to capture, process, and display the spectrum of frequencies in real-time, offering a comprehensive and instantaneous view of spectral activity, while preserving the time-domain information of the signal. This capability is critical for analyzing transient, rapidly evolving, or intermittent signals.
In contrast, non-real time spectrum analyzers usually take longer to sample and process their acquired waveform over a certain bandwidth. While processing these samples they can potentially miss brief, non-repetitive signals, which appear often in dynamic signal environments. Therefore, while traditional spectrum analyzers are effective for analyzing stable, cyclo-stationary signals, RSAs simplify the job of engineers working with applications requiring detailed, real-time observation of complex, and many times unpredictable signals.