Research On Coverage Of Hotspot Region With Small Satellite Constellation Design And Optimization

Facing with the increasingly frequent regional emergency tasks, there is urgent requirement to using the small satellite to obtain the spatial information for hotspot region. However, because of limited coverage area of the single satellite, an effective way to solve the problem is to build a constellation with many small satellites. Under this background, this thesis performs the research on the coverage of hotspot region with small satellite constellation design and optimization. The main work is as follows:1. Analyzing of the coverage characteristics of the satellites. Firstly, the performance index is analyzed. Then the coverage model of the satellite is established. The calculation of coverage area and the judgment of coverage conditions are analyzed and the computational process of coverage is presented. Finally the coverage characteristics of the satellite are analyzed and coverage area and capacity are discussed.2. Orbit designing and analyzing for the hotspot region. Firstly, after mission analysis of the orbit design for the hotspot region, the circular Low Earth Orbit is employed as the basic orbit type and the earth non-spherical perturbation is analyzed, which is one of the near-Earth orbit major perturbation. Then the influence on the performance of satellite coverage of the orbital altitude, orbital inclination, RAAN and the initial argument of latitude is analyzed by numerical simulation. Finally, the orbit design method of successive coverage and ground track repeat pointed to hotspot regional target is investigated.3. Designing and optimizing of coverage of hotspot region with constellation. Firstly, mission analysis of the coverage of hotspot region is conducted and high frequent successive coverage is selected as the way of coverage suitable for regional target. Then, according to the characteristics of the regional coverage, the same tracks of subsatellite point constellation is employed as the basic configuration of constellation for regional coverage and its principles and characteristics are analyzed. A design methodology and process for the coverage of the hotpot regional target is proposed and the design scheme is exhibited. Finally, the optimization method of regional coverage with constellation based on genetic algorithm is investigated and a simulation example is presented.4. Investigating of regional coverage constellation based on the orbital maneuver. Firstly, the method of constellation design based on orbital maneuver coverage is proposed and the orbital maneuver range by changing orbital altitude, orbital inclination and orbital phase is compared based on the analysis of orbital maneuvering capability. Then, the coverage range of orbital maneuver of a single satellite and the connection of coverage area of several satellites by changing orbital inclination is investigated. Finally, a constellation scheme which can realize the regional coverage by orbital maneuver with the same tracks of subsatellite point constellation is exhibited.The conclusion of the dissertation on the coverage of hotspot region with small satellite constellation design and optimization can supply a referenced plan and technical support for the regional space mission and has important theoretical and application value.