Guaranteed-Accuracy Positioning of Terrain-Following Unmanned Vehicles Using Tightly Coupled Integration of Satellite and Correlation-Extremal Navigation Systems

Currently, the integration of satellite navigation systems (SNS) and correlation-extremal navigation systems (CENS) for unmanned vehicles (UVs) is implemented based on principles of separate or, at best, weakly coupled integration, where their measurements are processed by different navigation algorithms (stochastic filters) with subsequent correction of inevitable discrepancies using various optimization methods. This approach is characterized by both high computational costs due to the need for parallel implementation of SNS and CENS measurement processing algorithms and subsequent optimization problem solving, as well as critical dependence of positioning accuracy on increasing levels of radio measurement interference. In this regard, a solution is proposed to improve the positioning accuracy of UVs based on the principle of tightly coupled integration, which involves representing the UV’s coordinate vector and the terrain elevation of the underlying surface as a single navigation vector, estimated by a common stochastic filter. Such measurement processing, in addition to significantly reducing computational costs, ensures robust and high-precision estimation of UV navigation parameters under conditions of intense interference of both natural and artificial origin. The results of a numerical experiment illustrating the effectiveness of the proposed approach are presented.