Orbital rendezvous represents a cornerstone in space systems engineering, as many critical mission rely on the ability to perform proximity maneuvers; among them are the assembly and maintenance of space stations (e.g. the ISS), crewed missions to the Moon (and, in the future, to Mars and beyond), and in-orbit servicing and active debris removal efforts. This master’s thesis has been conducted within the AOCS Department of OHB and has two main parts. The first will deal with the modeling of the relative orbital dynamics between two spacecraft in elliptic orbits, with a focus on the linearization process and the use of state transition matrix.