For medium and low latitudes, the N-hour repeating equatorial orbit is a new option for remote sensing satellites, which can realize multiple revisits per day, and revisit at the same local time revisits on different days. The remote sensing constellation formed by equatorial satellites could easily achieve rapid revisit, or even continuous observation. Therefore, the ground surveillance performance is critical for the system design of equatorial remote sensing constellations. In this paper, the latitude coverage characteristics of equatorial satellites are analyzed. This paper also assesses the constellation size required to achieve continuous observation of targets in different latitudes. The staring imaging time durations of satellites in the prograde and retrograde constellation are analyzed respectively.
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