Radio Frequency Propagation Modeling in the
Luciad GIS Based Terrain Analysis System (TAS)
Supporting Mission Planning and Force
Operations
Glenn Weathers, Applied Data Trends, Inc.
Brad Smith, SAIC
Harold Fears, COLSA
November 15, 2011
Contents
• Overview of the ADT Terrain Analysis System (TAS)
• Military value of functionality provided by TAS
• The TAS RF Propagation Analysis service in more
detail
– Including a RF propagation analysis, testing, and validation tool
implemented in Mathcad
• Current status of TAS
• Future development plans for TAS
Overview
• Product software was written in Java and operating
in the Luciad commercial GIS environment
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A TAS C++ version runs with ESRI GIS
• What was the primary advantages of basing the TAS
upon the Luciad commercial GIS?
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Ease and speed with which information can be presented
Copes with large data sets and can cover large study areas
Includes means to conveniently select any sub-study area
Copes with unlimited and frequent edits and changes
Robust, stable, and resistant to data loss
Fast and efficient execution
Productive development environment
Overview
• What was the primary disadvantage of basing the
TAS upon the Luciad commercial GIS?
– Diagnostic algorithms based upon a "step" size that had the potential
of "skipping" terrain features if set too large.
• Why was Luciad selected as the GIS to be the basis of
TAS?
– Luciad was easier to integrate into the objective services oriented
overarching architecture per software architects
• What is the operating system under which the TAS
executes?
– UNIX (Linux) but a port to Windows would be straightforward
Overview
• What is the software development environment?
– Eclipse IDE (Integrated Development Environment) with
calls to the Luciad libraries. Luciad was used to:
• Read data
• Manipulate geometry
• Generate line of sight between geometries
• Contour generation
– TAS Can process feature data in Oracle, DB2 and ESRI shape files.
– TAS leverages support for "complex query" capability like
"select all cropland features with a slope < 5%“
• Does the GIS vendor provide support during
development?
– The Luciad software package and documentation was an easy to
understand and use and Luciad provides good support
Military Value of TAS RF
Attenuation Analysis
• Planning command post or communications relay position
– Support RF communications with ground or air platforms or with dismounted
troops
• Planning ground or air maneuver routes
– platforms on these routes have RF communications support with one or more
fixed locations.
Military Value of TAS
Viewshed
• Planning the location of forward observer sites
• Planning the routes of UAVs equipped with electrooptical sensors
Military Value of TAS LOS
• Planning ground maneuvers to avoid LOS with known
enemy positions
• Planning direct-fire missions
Military Value of TAS
Discernability
• Planning operations with specific criterion involving feature data, for
example, finding a road with no line-of-sight to a specific enemy position
• Planning command post or platform positions where a building partially
blocks expected enemy RF communications jamming
• Planning a UAV electro-optical sensor mission that will have LOS to several
transportation features (roads) possibly in use by the enemy.
Military Value of TAS
Elevation Service
•Generate elevation profile for a point, line or area for planning
deployment of assets
•Determine slope and aspect at a point to plan to meet deployment
constraints
•Determine minimum and maximum elevations within an area to
search for potential observer deployment points
Military Value of TAS Intersections
• Calculate where a flight path trajectory will intersect terrain
and/or terrain features such as buildings to aide in flight
planning
• Returns vector information for each intersecting segment.
– geometry
– Feature information
Military Value of TAS Region of
Influence
• Used to generate a buffer zone around a given feature in
the terrain
– Example: buffer zone around a linear feature
Military Value of TAS
Traversability
• Find limiting factors to vehicle movement along a
route to aide in maneuver planning
TAS Support of Critical Military
Operations Planning Functions
• TAS provides functionality to other planners
• RF Propagation/Attenuation Modeling
– Communications Network planning
– Sensor planning
– Force Protection planning
• LOS/Viewshed
– Course of Action planning
– Sensor planning
– Force Protection Planning
• Discernability
– Maneuver planning
TAS Support of Critical Planning
Functions
• Intersections
– Mission planning
– Maneuver planning
• Region of Influence
– Course of Action planning
– Mission planning
– Fires and Effects Planning
• Transversability
– Maneuver planning
TAS: RF Propagation Analysis
• Requirement to calculate attenuation from Site 1 to
all possible locations of Site 2 in a map area.
– Deliverable product written in Java and operating in the Luciad GIS
environment
– System Engineering efforts used Mathcad as a means of generating
“Executable Specifications”:
• Support testing of the mathematical models and algorithms
• Verify Java/Luciad implementation by comparison of results
RF Propagation Models
• Sky Wave
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Direct path
Reflection path
Atmospheric refraction
Atmospheric absorption
• Ground Wave
– Diffraction path
• Terrain blockage
• Structure blockage
• Vegetation attenuation
• Weather attenuation
Area of South Korea Used for Test and Analysis
Terrain View: Color Coded Elevation
Terrain:
1200 arc-second
By
1200 arc-second
(Approximately
40 KM by 40 KM)
Centered on
36 degrees 40 Minutes
North Latitude and 126
Degrees 40 Minutes East
Longitude
(An area of South Korea)
Terrain resolution: 12 arc
second samples
Example:
Site 1 Radio location is the
center of the map indicated
by the intersection of the two
white lines
Test Area 3-D Terrain View
Typical Mathcad Based Tool Results
RF Attenuation
Contours in dB
Antenna H1 = 10 m
Antenna H2 = 2 m
Frequency = 400
MHz
Mathcad Attenuation Versus Frequency
Animation
Sweep
Frequency from
20 MHz to
2 GHz:
Attenuation with
One Contour at
177 dB
Threshold Level
(defines “no-go”
areas)
Click in
Graphic
Mathcad Animation of Moving Transmitter
Click in Graphic
TAS: Current Status
• Functionality implemented via TAS and currently
available through the TAS I/O Kit.
– RF Attenuation
– LOS/Viewshed
– Discernability
• Functionality implemented in TAS but to become
available through the TAS I/O kit.
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Elevations
Intersections
Altitudes
Region of influence
Transversability
Feature Attribute
Planned TAS Enhancements
• Automated assistance in placement of
communications terminals and sensors
– Suggest best locations to the warfighter based upon RF propagation,
LOS/Viewshed, and using Discernability for best relationship to GIS
feature data such as transportation features
• Include acoustic propagation modeling to support
automated acoustic sensor placement
• Enhance RF propagation modeling to better support
electronic warfare planning
Planned TAS Enhancements
• Add weather effects for
– Viewshed/LOS
• Add solar/lunar shading capabilities
– Viewshed/LOS
• Add a smart “trade-off” algorithm controlling
geospatial sampling step size to make sure all
buildings are considered while controlling memory
use and run-time.
– Viewshed
– RF Propagation
Questions