Extended Data Fig. 2: QBER contribution of noise and satellite elevation angle as functions of time.
From: Microsatellite-based real-time quantum key distribution
The transmitted vacuum state allows for the assessment of the polarization-independent QBER arising from factors such as background noise. In urban environments, background noise is a dominant contributor to the QBER, particularly at low satellite elevation angles where received photon counts are reduced. This impact varies depending on ground station ___location, time of day, and weather conditions. Employing spectral filtering with narrower linewidth and spatial filtering with smaller field of view can further mitigate this issue.
