DEMETER: Conventional Infrastructure Assessment and Optimization

DEMETER: Conventional Infrastructure Assessment and Optimization

With PBN providing the ability to redesign ATS routes without the necessity of overflight of ground-based navigation facilities thus delivering operational benefits, an assessment needs to be made if the current facilities provide sufficient coverage to enable RNAV based on DME/DME positioning. DEMETER models facility coverage using a terrain database and assesses how RNAV functions can be supported. Specific features help determine where navigation aids can be rationalised (VOR) and where new facilities may be needed (DME).

Distance Measuring Equipment Tracer is a software tool, which supports the implementation of Performance Based Navigation (PBN) and the optimisation and rationalisation of navigation infrastructure.

The tool enables simplified collaboration between airspace planners, procedure designers, Navaids engineers and flight inspectors for establishing DME/DME positioning as a continuous ground-based back-up solution to the Global Navigation Satellite System (GNSS).

DEMETER is designed to assess the space performance of DME/DME signal in en route and TMA airspace. It can also be used to determine the ground infrastructure needed to support Area Navigation applications, like RNAV 1 for SIDs and STARs. This is done in accordance with EUROCONTROL’s guidelines on RNAV 1 infrastructure assessment (EUROCONTROL-GUID-114, Edition 2) as developed in cooperation with the ICAO Navigation Systems Panel (NSP) and endorsed by the Performance Based Navigation Study Group (PBN). The software tool also supports the assessment of VOR/DME coverage and redundancy in support of RNAV 5 applications.

DEMETER is currently used by Air Navigation Service Provider (ANSP) organisations in most ECAC (European Civil Aviation Conference) member states as well as globally by other organisations providing flight inspection or procedure design services, research institutes and universities.

SESAR projects have used DEMETER for the ECAC-wide assessment of the ground navigation infrastructure to evaluate the rationalisation potential and identifying optimisation solutions.

Main Features

DEMETER’s main features and functionalities include:

• Integrated Navaids database for ECAC states supported by EUROCONTROL and Air Navigation Service Providers (ANSPs);
• Import of Navaids data from either EAD snapshot reports in AIXM 4.5 and 5.1 formats, ARINC424 data files or from flexible .csv format;
• Import of airspace elements (e.g. coordinate points, SID/STAR procedures, route segments) from EAD snapshot reports;
• Integrated GTOPO30 terrain database with support for high quality DTED levels 1 and 2 and other formats such as: SRTM, ASTER, GeoTiff, ASCII DEM, ARCINFO GRIDs;
• Coverage calculations based on Line-of-Sight, Free Space Path Loss or Diffraction propagation models;
• Co-channel separation checks, including 8dB D/U evaluation;
• DME-DME coverage and performance assessment, as well as VOR-DME coverage and redundancy assessment;
• Estimation of best location for a new DME site that together with the existing navigation infrastructure helps improve the DME-DME signal coverage in a designated area of interest;
• SID/STAR procedure definition including the RF legs, DME/DME performance calculation, and individual DME coverage prediction in vertical profile;
• Estimation of INS drift over coverage gaps;
• Batch processing (calculations queueing);
• Support for flight inspection planning on SID/STAR procedures, minimising the number of runs needed;
• Predefined Flight Inspection data formats as well as a flexible importing interface and pre-processing function allowing direct comparisons between predicted and achieved coverage;
• Import of RNAV Validation Tool (RVT) trajectories;
• 3D terrain and simulation results visualisation using NASA WorldWind;
• Import and management of SAAM (NEST) Traffic Densities
• Import of user layers in shapefile, tiff and .kml formats;
• Export of 2D map layers in shapefile and .kml formats;
• Export of 2D map and simulation results to usual image formats.

Latest version

The latest version of DEMETER (v3.1.0), released in December 2021, introduced a number of bug fixes and improvements such as:

• Default Project, non-editable;
• Coverage Quantitative Assessment Tool (applied to DME-DME redundancy assessments);
• Calculations with Altitude Above Ground (in Coverage Assessment Tool);
• NavAids Filtering;
• Filter FIR UIR;
• Rename Calculations;
• ARINC 424 Figure of Merit (FOM) max altitude;
• Use FOM instead of DOC limitation (in Coverage Assessment Tool);
• Visualize Fix Points coordinated in Leg Definition;
• Procedure Analysis export results, graphs copy to clipboard and tables export to CSV;
• Export image/Print Map – Preview, choose the legend position and copy to clipboard;
• Change Date formats;
• Various improvements and bug fixes.

A factsheet describing the latest features that are provided in DEMETER 3.1.0 can be found here.

Access

EUROCONTROL stakeholders may obtain DEMETER and its associated technical documentation free of charge.

As DEMETER works globally, other interested parties area may also request the software. The support provided by EUROCONTROL in this case may be limited and users might need to import their own navigation aids data.

Access can be requested via the OneSky contact form available here or by writing directly to the DEMETER team at DEMETER@eurocontrol.int.