Geometrical approach for an optimal inter-satellite visibility

In the field of satellite constellations, an important requirement is often represented by the possibility to exchange data among the satellites or exploit mutual visibility to carry out measurements on the parameters of the Earth’s atmosphere. Therefore, recursive and routing algorithms are usually implemented to evaluate inter-satellite visibility intervals. However, to design the configuration of the constellation, it is important to consider the orbital conditions that guarantee the mutual visibility between couples of satellites. Thus, in this study, a geometric analysis was performed to identify the optimal inter-satellite visibility conditions, expressed in terms of the difference in the true anomaly between satellites characterized by different orbital configurations. This approach allows a handy constellation design, without performing a numerical analysis. It is particularly useful in the case of a high number of satellites, when numerical techniques require significant computational effort. Therefore, it is possible to considerably simplify the design of a constellation in which the mutual visibility between couples of satellites is always guaranteed. This type of constellation, usually referred to as satellite chain, can be exploited in several network services and remote sensing systems devoted to enhancing the knowledge of atmospheric parameters.