Proposal and Investigation of a Processing and Bandwidth Resource Allocation Strategy in LEO Satellite Networks for Earth Observation Applications.

The processing capacity available on satellites within Low Earth Orbit constellations allows for the implementation of data processing on-board of satellites. Furthermore, by endowing satellites with Inter-Satellite Links, it is possible to obtain a network within the constellation, enabling data routing and allowing processing to take place on any satellite of the constellation, even different from the task originating one. Edge computing solutions for Earth Observation (EO) applications have been proposed in satellite environments, where the data processing is accomplished by either the satellite running the observation task (Always First) or by a datacenter connected to a ground station (Always Ground). We propose a solution in which any satellite of the constellation may process the EO task and its choice is performed so as to minimize the sum of the memory, processing and transmission costs. We propose and evaluate the effectiveness of a heuristic that jointly performs the following operations: i) the choice of the element (satellite, datacenter) performing the task processing; ii) the choice of the routing path on which the task or its processing result is routed from the observation satellite to the datacenter. The proposed solution is compared to the Always First and Always Ground benchmark solutions and both the cost advantages and the potential delivery delay reduction are evaluated.