On the Selection of Multi Optimal Imaging Frames in Single Time Slot for Earth Observation Satellite

This paper concentrates on the problem of multi optimal imaging frame selection in a given time slot for earth observation satellite, which orbits the earth and acquires images of specific areas at the requests of users along the orbit through rolling the lens. Area targets are taken into account. First, the reward rate of each observation request is sampled at specified space resolution. Then reward values of all the candidate imaging frames in the satellite´s covering of land belt at given time slot are calculated through row accumulations followed by column accumulations. Second, the candidate imaging frames are modeled as a directed acyclic graph; where each node is a candidate imaging frame with the reward value greater than a threshold and the directed edges imply the reachable successive imaging frames with the constraints of earth observation satellite scheduling. At last, the maximum rewarded path which satisfies the constraints is acquired as the result of the optimal imaging frames through an A* searching algorithm. Experiments with random observation requests validate these algorithms.