Research And Realization Of GNSS Integrated Navigation Algorithm

With the development of satellite navigation system, it has played an extremelyimportant role in the military and civilian areas, and become an important force tosafeguard its national interests and promote economic development. Following theGPS system of the United States, some countries have also started the construction oftheir own satellite navigation system based on their own national interests, such asRussia’s GLONASS, European GALILEO and China’s BeiDou system. The rapiddevelopment of those satellite navigation systems brings developmental opportunityfor GNSS integrated navigation which has a higher security, reliability andpositioning accuracy. Based on this, this thesis studies the key problems of GNSSintegrated navigation.Firstly, fundamental principles of satellite navigation system are described briefly,different time and coordinate system which are adopted by each satellite navigationsystem are introduced, and the uniform method of different time and coordinatesystem are given in order to solve the compatibility problem of integrated navigationsystem.Secondly, aiming at the ionospheric delay which is the main error for satellitenavigation system, traditional correcting methods and their characteristics areintroduced, an ionospheric correcting method is proposed by using inter-frequencybias, and the superiority of the algorithm is verified by experimental data.Finally, in order to balance the quantity of computation and positioning accuracy,the satellite selection algorithms are studied, an improved algorithm is proposed afterintroducing two traditional satellite selection algorithm, and the simulation resultsshows that this method greatly reduces the amount of computation under the premiseof ensuring the positioning accuracy.