Space Based Air Traffic Management Concepts, Mission Analysis & Differential Air Drag Controller Design and Development

The aim of this study is to show and underline the effective capabilities of the Cubesats platform, nowadays even more used over the pure scientific-purpose demonstration. The Air traffic management is actually one among the most studied sector in the aeronautic field, to lead to an even more safe ambience. According to international agencies guidelines, there is the will to standardize protocols to make the flight transportation, the safest way to move around the world. Consequently, a lot of rules and laws have been made, for instance by International Civil Aviation Organization, ICAO, to provide the maximum of the safety possible. Among the recent standards adopted, the members states of the ICAO proposed the adoption of a new 15 min aircraft tracking gap allowed, this both to reduce the so-called “safety-bubbles” used in the route planning, and then reducing the fuel cost, optimizing the paths, and also to reduce the search-andrescue bottleneck that a lack of tracking would lead to. Unfortunately, in some areas of the world, this standard actually cannot be accomplished, due to the impossibility to provide adequate infrastructure. IE, North Alaskan and oceanic zones. On the other hand, some recent mission like as GOMX, operated by GomSpace ApS, demonstrated the feasibility to use the ADS-B Rx/Tx in space, leading to the possibility to use optimized constellation of small satellites in low Earth orbit, to receive signals from aircraft and relay it to ground station. Under this general objective, the purpose of the thesis has been to study some Orbit Design to optimize design variables like: constellation type, number of 5 satellites, orbital parameters, according to constraint as Area of interest, simulated air traffic and receiver characteristic. Not only, to better understand the Cubesat Constellation capabilities, one other concept has been studied in deep: the Differential Air Drag control. The Cubesats platforms are nowadays among the most cheap and reliable options for several kind of purposes. On the other hand, their reduced size lead to some constraint, like a reduced control capabilities, especially regarding the orbit control, while the Attitude is, in general, well granted by several system, especially in Low Earth Orbit. A new concept to provide orbit control, without the requirement of huge DeltaV capability onboard but that rely on the ability of our spacecraft to change its attitude relatively easily, is the Air Differential Drag control, which main idea is quite simple. Indeed, offering different Cross-Area to the velocity direction, we are able to change the orbit degradation time, modifying the relative speed between two units in our constellation without the use of any kind of fuel. An algorithm in Matlab has been developed, to study at first the effective possibility to use this concept to phase our satellites in a reasonable amount of time without a too excessive orbit degradation and at second to provide the control profile, through the time spent in each drag profile, high or low. In conclusion, starting from data obtained from several past researches, including ones focused on cubesat capability to receive ADS-B signal, as well as similar researches on the possibility to use nanosatellite constellation to improve the ATM situation, we derived a set of feasible constellation, together with a control concept able to spread our satellites along the orbit chosen, almost consumptionfree.