Weighted Data Processing from DME/DME and VOR/DME Position Sensors

Modern civil aviation uses a variety of positioning sensors on board of airplane to guaranty safe navigation. During the last decade Global Navigation Satellite System has shown its vulnerability to radiofrequency interference. That makes navigational aids useful for a stand-by positioning sensor on board of airplane. Methods of positioning by data from distance measuring equipment (DME) and VHF omnidirectional range (VOR) are more commonly used due to required accuracy level according to performance-based navigation. In the paper, we consider airplane coordinate fusion provided by DME/DME and VOR/DME positioning methods. Both positioning methods provide results with different configurations of uncertainty areas. On-board flight management system made a decision on sensor to be used in further computation based on maximum level of performance. Fusion based on maximum likelihood function helps to make a decision on airplane position based on two input sensors and minimize mean standard deviation error based on configuration of uncertainty area. Proposed approach has been verified by computer simulation with a real airplane trajectory data obtained from Automatic Dependent Surveillance–Broadcast open database. Simulation results using real flight data from a WZZ1273 trajectory demonstrate a maximum reduction of 23 m in standard deviation error at specific time points, highlighting the effectiveness of the weighted fusion approach in enhancing positioning accuracy.