Coordinates data fusion with probabilistic approach

The paper is devoted to the task of positioning that plays an important role in navigating an aircraft in airspace, the accuracy of which depends on the safety of aviation. The paper considers the most common avionics of civil aircraft that includes equipment of Global Navigation Satellite System (GNSS), Inertial Navigation System, and area navigation positioning algorithms within Flight Management System (FMS) functionality for positioning using signals from navigational aids. Each of considered equipment meets the required level of accuracy, continuity, and integrity of coordinate data, which depend on a variety of factors. In terms of global availability and the best accuracy, GNSS is considered as a primary source of data, however positioning by navigational aids data can be used in case of GNSS lock or pure accuracy positioning. In addition, the paper regards different algorithms of coordinate’s detection in FMS: positioning by Distance Measurement Equipment (DME) realizing time of arrival method, positioning by VHF Omni-directional radio Range (VOR) or Automatic Directional Finder (ADF) data that uses angle of arrival methods. Data fusion process is considered at different levels. VOR/DME data processing is represented at the paper as a particular case of low-level data fusion. A block-diagram of sensor coordinate data fusion that includes lower level of sensor data fusion and multi sensor coordinates fusion from pair based and multi sensors approaches is proposed. Proposed approach of data fusion is grounded on weight coefficients that indicate accuracy of each positioning algorithm at high level of integration. At high level of data fusion, a probabilistic approach for a case when the distribution of measurement errors have Gaussian form is proposed. Verification of probabilistic data fusion approach has been performed with iterative computer based simulation. Trajectory of AUI58 flight was recorded by ADS-B equipment and used in simulation part. Stochastic simulation of DME and VOR measured data was used in pair-based (DME/DME, VOR/DME, VOR/VOR) and multi navigational aids algorithms of coordinates detection. Results of simulation indicate the possibility of data fusion weighted algorithm application for civil aviation.