The Research Of Integrated System On Sins/land-based Radio Navigation

The complex electromagnetic environment makes advanced demands of the missile's navigation system. This thesis studies the integrated navigation system based on SINS and land-based radio system, which possesses high precision, good reliability, and strong anti-interference characteristics.At first place, in this thesis, the theory of strapdown inertial navigation system is analyzed, its arrange equations and error analysis are discussed, the attitude matrixes are updated with the quaternion algorithm. The trajectory of ballistic missiles and the models of gyroscopes and accelerometers are built and simulated based on the theory analysis and characteristics of ballistic missiles.Secondly, researches have been carried on the land-based radio navigation system, the GDOP(geometric dilution of precision) and the error sources. The operating principle of radio distance measuring is expatiated. Two key problems, pseudo-random sequence and acquisition, in spread spectrum systems are also studied in this thesis. By working over the autocorrelation and cross-correlation of the m sequence and comparison of the different coding acquisitions technologies, this thesis adopts m shift sequences and FFT-based acquisition method to analysis the actual measurement data.This thesis also investigates the integrate models of SINS/ land-based radio and integrated navigation system, established the integrated mode of position and velocity. At the same time, the state and measurement equations of Kalman filter are established. Comparing with SINS, the simulation example of position-velocity integrated Kalman filter shows that the integrated navigation system can enhance navigation precision and meet the navigation requirements.