AIRNAS is a multi disciplinary integrated design environment (Framework) based on CAD and simulation techniques capable of concurrently dealing with problems related to:

the different phases of air navigation design (e.g.: en-route, landing, missed approach, etc.) the various tasks involved in system choices and performance evaluation of Navaid and ATC systems.

AIRNAS is composed of an aeronautical Data Base, a GIS (compliant with aeronautical requirements), a 3D CAD (fully integrated to the GIS), a module library implementing the ICAO-PANS-OPS design criteria and a library of electromagnetic simulation tools.

AIRNAS is conceived to be capable of assisting both the AIS designer and the Navaid-ATM/ATC designer.

AIRNAS Major functional blocks.

As depicted in the conceptual scheme above, AIRNAS is composed of three major blocks, namely:

EMACS: ElectroMagnetic Airport Control and Survey.
FPDAM: Flight Procedure Design and Airspace Management,
Aeronautical Data Base for archiving all design relevant data and all elements concurring to the safety of flight procedures and Air traffic control.

The system is based on a layer of graphical and geographical functions:
Graphical utilities (Computer Aided Drawings) for the construction and visualisation of 3D elements. Geographical utilities (Aeronautical Geographic Information System) for locating elements on a geographic continuum using WGS 84 (GPS adopted reference system).

FPDAM is a three-dimensional CAD tool that provides an interactive environment for Aeronautical Flight Procedures design, Air Space management and Air Navigation using the new GPS based concepts.

FPDAM takes into account all factors affecting flight procedure performance (airdrome terrain model, artificial obstacles, type of aircraft, ICAO Rules, GNSS satellite constellation etc.), within an interactive environment capable of ensuring a tight control on the system configuration and on all elements and design criteria related to flight safety issues.

EMACS is a set of validated electromagnetic 3D modelling and simulation tools, capable of coping with EMC (ElectroMagnetic Compatibility issues and EMI ElectroMagnetic Interference problems in airport and air navigation site scenarios. The modelling functionality (including terrain models, obstacles, interfering system, ground and airborne navaid equipment characteristics etc.) allows an expert user to model the propagation real phenomena taking place within a complex e.m. airport scenario where signals (VOR, DME, ILS, ATC Radar, GPS systems) interfere with artificial or natural obstructions.

EMACS design environment and major simulation modules EMACS Modular Architecture

EMACS SW package comprises the Software modules listed below :

SiteModelling which allows the user to perform the following functions:
Navigate across the country geographical continuum using different Datum (WGS-84 and ED-50).
Perform queries by mouse on aeronautical features, compliant with ICAO symbolisation rules, for viewing site locations, element characteristics (airport, Navid, Radar) etc.
Perform zoom in/out for viewing a large aeronautical area of interest with aeronautical elements as thematic overlay (e.g. interdicted areas, SID,STAR airways, envelope protection, etc.) or for viewing geometrical details of the airport site (e.g. runways, hangars, buildings, tower, pylons, etc.) and Navaid locations
Build a terrain 3D model of the area of interest (DTM) by using the most appropriate scale for the contour level maps, break-lines, coast line and other useful features.
Build the 3D geometric and electromagnetic model of the airport or navigation site on a layer superimposed onto the reference ICAO map. Site 3D models are archived into the Data Base where only authorised users are allowed to manipulate these files by adding new objects or modifying existing object characteristics (location, dimensions) to perform what if investigations.

Site Modelling include e.m. meshing tools matched to the frequency of interest and the obstruction relevant details.

Other functions are:
Airport/navigation site 3D model construction and geo location on to the cartographic system, including Geo location of raster data (airdrome charts, ICAO obstacles charts, maps .)
FPDAM Air Traffic Service 3D : graphic data visualization of flight procedures, routes, zones, navigation aids, reporting points, airdromes and runways...
Graphical Data Base query to the navigation system Data Base Server.
Airdrome Obstacles and AIP Obstacles Positioning and management.
Navigation aids display, tracks, bearings, fix, tolerances computation and design,
3D Artificial obstacle positioning on the airport site by selecting objects from a library of pre-defined and scalable 3D objects such as hangars, buildings, towers, antennas, fences, pylons, etc. or by constructing customized model by means of the 3D CAD utilities.
Passage from FPDAM ICAO aeronautical views to EMACS e.m. views and vice versa since the two environments share the same graphical engine (Microstation)

Radar: allows users to perform the following investigations:
Predict, for a chosen location, the electromagnetic compatibility with obstacles to the correct signal propagation including:
- Pattern Distortion measured by OBA (Off Bore sight Antenna error) caused by nearby obstructions.
- Unwanted azimuth reflections that might cause false echo appearances
- Near Field radiation hazard for maintenance personnel.
Predict, for the site installed antenna, the realistic coverage over selected flight levels (FL) for reference radar cross section targets. The antenna far field radiation pattern will take into account near field distortions.
Predict the Clutter Map over given polar areas accurately modelled by means of facet geometry and reflectivity properties.
Predict EMI with other radiating receiving systems with the specific radar playing the victim or threat role. Interference analysis is performed by means of the Inter System EMI module.

ILS/LLZ-GP: allows users to perform ILS compatibility analysis and Interference mitigation, for new or improved runways, according to task specific procedures such as:

New ILS site selection
To carry out these investigations user will have to take into account ILS route and clearance signals, 1F or 2F systems, including all significant ILS parameters such as SDM, DDM, A90, A150 etc..

Compatibility with new obstacles (e.g. for planning permission purposes).
In band and out band Interference investigations with nearby fixed or mobile emitters to verify whether unwanted signal might cause false DDM indications.

VOR-DME module provides EMC analysis on navigation sites by enabling what if inspections on nearby obstacles and terrain, counterpoise platform extension and height and antenna type. Available procedures cover the VOR antenna siting and the compatibility assessment with new obstruction in navaid sensitive area.

TLC modules provides EMC/EMI analysis on TLC radiating systems (V/UHF air to ground communication) and signal strength predi ction analysis on airways and airspace. Procedures available provide users to predict coverage and e.m. compatibility of Ground to Air antenna installed on towers or pylons and permit intra (co-located antenna) and inter system EMI analysis with navaid.
GNSS_siting (Siting for Ground Station for LAAS, Rims), under integration, available by Q1-98

InterSystem Emi provides user with a set of e.m. propagation tools capable of predicting system coverage over terrain including artificial obstacles. It also provides inter system interference ratio evaluations for power spectrum and frequency management purposes. All system data are imported from equipment data base archive. User define the interference inspection by selecting the Victim system (fixed or mobile), its location or path, the Threat -TXs of interest (within a given area).