High precision autonomous localization method for high altitude and long-flight-time of unmanned aerial vehicle

In allusion to the limitation of the traditional navigation and localization method of stellar horizon atmospheric refraction based on the orbit dynamics models and nonlinear Kalman filter in practice application, a novel navigation and localization method of rapid stellar horizon atmospheric refraction which is suitable for high altitude and long-flight-time autonomous navigation and localization of unmanned aerial vehicle is proposed. The measurement mechanism of celestial navigation is analyzed, based on the measurement equation of the sight-altitude of stellar horizon atmospheric refraction, and the equation of three-dimensional celestial localization using the stellar horizon atmospheric refraction is deduced. The novel celestial localization method is introduced in detail which utilizes the least squares differential correction method instead of the nonlinear Kalman filter. The precise position information of the unmanned aerial vehicle can be obtained by solving the nonlinear measure equation set directly. Moreover, the theoretical analysis of the localization precision of the novel stellar navigation and localization method is given. This stellar localization method uses the characteristics of the stellar horizon atmospheric refraction, and does not need the dynamics model of an aircraft and any prior knowledge. Further more, the proposed method is easy and reliable, the calculation load is lower, while the localization precision is equivalent to the traditional stellar horizon atmospheric refraction method. In the end, the simulation results show the validity of the proposed stellar localization method.