Simplified method for predicting the system response time of satellite constellations

Abstract A new method for estimating the system response time (SRT) of satellite constellations is proposed. The presented method computes the access time intervals for each satellite in a satellite constellation to every ground station in the network and target. When analyzing the SRT from global targets this method significantly simplifies the computational process. The spatial dimension of the computational problem is reduced by using a Monte Carlo simulation for the observation targets. The temporal dimension is simplified by discretizing the chosen simulation interval into equally spaced time points. This makes our approach efficient for calculating the SRT on global targets. Based on these access intervals, the SRT is calculated for each discretized time point and target. Averaging the SRT over the time points extracts time-independent information. This yields meaningful metrics such as the average, minimum, and maximum SRTs of the targets. Combining these metrics with a visualization on a world map allows for a quick understanding of the strengths and weaknesses of the constellation with respect to SRT. We demonstrate this method using multiple scenarios ranging from a single satellite and ground station to larger constellations and ground station networks. Investigating the SRT as a function of target latitude [ $$-90^{\circ }$$ , $$90^{\circ }$$ ] reveals that it peaks at the equator and drops towards the poles. The specifics of this curve depend on the number and design of both the satellite constellation and the ground station network.