Construction of an optimal flight trajectory in the glonass accuracy field

Advanced technologies of air traffic management suggest changing-over to free routing (procedures for dynamic change in the flight route) in order to improve the efficiency of aviation transport. These technologies are based on the Performance-based Navigation (PBN) concept and the use of satellite navigation systems. However, the accuracy of such systems depends on the position of navigation satellites with respect to the user and is different in the provided airspace. That is why the optimal flight trajectory must be constructed with account of its reliability in the varying accuracy field of the satellite navigation system. The accuracy field can be defined by the values of the geometrical dilution of precision (GDOP). To construct the trajectory the authors relied on the optimization criterion and chose the A* algorithm (A star) implemented in the LabView graphical programming environment. The software package for simulating the GLONASS orbital movement and computing the accuracy fields within the provided airspace was implemented in the LabView as well. Using the mathematical modelling the authors constructed optimal flight trajectories in the GLONASS accuracy field with some prohibited zones within the provided airspace.