Key Technologies Of Autonomous Operation For Navigation Satellite Constellations Using Inter-satellite Tracking Data

In order to enhance the ability of navigation battle and meet the requirement ofsolving the restriction of the regional monitoring station network, it is a generaltendency to build Inter-Satellite Links (ISL) in the next generation of the globalnavigation satellite system (GNSS). Bsed on crosslinks the autonomous navigationtechnology is carried out. This dissertation analyzes a variety of technology ofnavigation satellite constellation autonomously operation, proposes the autonomousnavigation algorithm based on inter-satellite link technology, designs the algorithm ofautonomously updated broadcast ephemeris, studies autonomous control technology ofnavigation satellite constellation structure evolution and constellation configuration.The main research contents are as follows:The conceptual design and analysis for navigation constellation with ISL arecarried out.(1) The architecture of multi-layer links of navigation constellation isstudied and designed, and a geometric model of link in constellation is built.(2) Afteranalysing the dynamic topological structure of ISL, a method of estimating autonomousnavigation error is proposed based on the satellite positioning principles.The research on the algorithm of integrated estimation based onSpace-Ground combined orbit determination of navigation constellation.(1) Themethod of combined orbit determination based on the EKF is studied. In order toimprove the accuracy of the navigation constellation, the simplified Sage-Husa adaptivefilter is introduced to estimate the covariance matrix of measurement noise.(2) Themethods of Space-Ground combined orbit determination of navigation constellation arepresented based on UKF, which enhance the accuracy on linearization process andenrich the theory of “joint estimation” of the satellite orbit. The simulation results showthat the method can improve the accuracy of the orbit determination obviously.The research on the algorithm of the space-borne distributed orbitdetermination based on EKF and the strategy of the constellation autonomousnavigation based on ground-based “anchor”.(1) The algorithm of the space-bornedistributed orbit determination based on EKF is presented. The algorithm utilizes statedecoupled in filtering and deposes the observation data which is only related to thenavigation satellite itself. So it reduces the computation largely to meet capability of thespace-borne computers.(2) The strategies of the constellation autonomous navigationbased on ground-based “anchor” are introduced. And the strategies solve the navigationconstellation orbit determination by only using inter-satellite crosslink measurementsduring auto-navigation period and overcome the datum mark deficiency problem of thenavigation constellation autonomous orbit determination.The research on the ephemeris autonomously updated technique of navigation satellites.(1) In order to solve the singularity of the normal matrix in the process offitting, the algorithm of broadcast ephemeris parameters autonomously fitting ispresented based on the non-singular transformation of the orbital elements, which canbe applicable for the orbital eccentricity equaled to zero approximately. Theautonomously fitting algorithm of18parameters of GPS broadcast ephemeris is alsostudied, which enhances the precision of the secular predicting of the navigationsatellites and can be engineering realizable.(2) The fitting algorithm of clock errorparameters of the navigation satellites is studied, and the method of the estimation andprediction for clock error is designed based on generalized EKF.The research on analysis methods of the navigation satellite constellationstructure evolution and the technology of constellation configuration autonomouscontrol.(1) Considering the constraint relations between the configuration evolutionand the autonomous operation of satellite constellation, the analysis methods are studiedon the evolution of the single satellite orbital, the evolution of the constellationgeometry configuration and the configuration evolution of the regional coverageconstellation.(2) The optimization criterions of the most superior constellationconfiguration transformation are established that considers the constellationconfiguration autonomous control sequences to meet equal time length distribution. Andthe criterions also adopt the coordinated control between the semi-major axis andinclination, which enhance the long term stability of the satellite constellationconfiguration.The dissertation investigates some key technology of autonomously operation ofthe navigation satellite constellation based on the ISL and ground-based “anchor”,which exploratory research resulits would avail to pave the way for further researchesand experiments, and also would have certain reference values for the global navigationsatellite system construction.