Research On GNSS Multi-system Satellite Selection Strategy

Beidou satellite navigation system (BDS) is our independent designand development global satellite navigation system which is running onlyby nation government. Beidou satellite navigation system has graduallybeen establishing and becoming perfect. The need of integrated navigationof GPS and BDS is gradually emerging, so it is realistic to research selectionstrategy of integrated navigation of the two systems.Some relatively in-depth and detailed theoretical study has been doneon GPS, BDS and integrated navigation of GPS and BDS. Forsingle-system and multi-system, corresponding satellite selection strategywas put forward which aimed to low calculated quantity as much aspossible as the prerequisite was to guarantee the effect of positioning.This thesis is mainly focusing on the following aspects:1.Domestic and international research of satellite selection algorithmswas summarized, and a detailed introduction was brought to GPS and BDSsystem components, spatial coordinate systems, time systems, positioningprinciple and methods to get satellite position and propagation time ofsignal.2. Least square method to solve user location was introduced. Thelinearization of least square method was used to derive GDOP and factorswhich affect GDOP were discussed. Existing single-system andmulti-system satellite selection algorithms were introduced in detail,respectively.3. For deficiencies of existing single-system satellite selectionalgorithms, a new satellite selection algorithm was brought based on optimum geometry and two-dimensional convex hull. Verification,comparison and analysis of single-system selection algorithm under thecircumstance of GPS and BDS was proceeded with, which had proved thatthe satellites selection algorithm based on optimum geometry andtwo-dimensional convex hull was able to achieve a balanced betweencomputation and performation of positioning.4. The roles of each kind of Beidou satellites were preliminarilystudied. Two kinds of application scenarios of multi-system were studied.In the application scenarios of multi-satellite of multi-system, amulti-system gift-wrapping satellite selection algorithm was proposedbased on optimum geometry and two-dimensional convex hull.Comparison with other methods, the multi-system gift-wrapping satelliteselection algorithm based on optimum geometry and two-dimensionalconvex hull was able to achieve a balanced between computation andperformation of positioning.