Boxcar averagers are attractive tools to achieve a high signal-to-noise ratio (SNR) in a minimal amount of measurement time when working with low-duty-cycle signals. Such signals contain relevant information only in a fraction of each period; outside that fraction only noise is present. Capturing low-duty-cycle signals with high quality and the ability for real-time feedback is crucial in many applications in optics and photonics, nanotechnology and materials science, quantum technologies, scanning probe microscopy, and sensing.
The graphic below illustrates the principle of boxcar averaging: limiting the measurement to a well-defined temporal window in each period (in grey) means that all signal components outside of that window are rejected.