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Matthew Allen – ECE
Allen Blaylock – ECE
Benjamin Davidson – ECE
Group 105
9/1/2015
Modeling Maritime Radar Scattering
WPI Major Qualifying Project
MIT LL Advisor:
Dennis Blejer
WPI Advisor:
Edward Clancy
This work is sponsored under Air Force Contract #FA8721-05-C-0002. Opinions, interpretations, conclusions and recommendations are those of the author and
are not necessarily endorsed by the United States Government.
Allen, Blaylock, and Davidson - 2
9/1/2015 UNCLASSIFIED
• Introduction
• Ocean Scattering Simulation
– 1-D Model
– 2-D Model
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Outline
Allen, Blaylock, and Davidson - 3
9/1/2015 UNCLASSIFIED
• Small boats and semi-submersible boats are being used by drug-runners, smugglers, and pirates
• Small boats loaded with explosives present a threat to the security of our naval forces
• The first step to counter these threats is detection
• Currently, lack of data and understanding inhibits detection
Introduction
USS Cole
Semi-Submersible Sub
Allen, Blaylock, and Davidson - 4
9/1/2015 UNCLASSIFIED
• Introduction
• Ocean Scattering Simulation
– 1-D Model
– 2-D Model
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Outline
Allen, Blaylock, and Davidson - 5
9/1/2015 UNCLASSIFIED
• Single fixed antenna
• Determine range and velocity information of boats and ocean surface
• Time Delay Range
• Frequency Shift Velocity
Radar
http://www.radartutorial.eu/01.basics/rb05.en.html
Allen, Blaylock, and Davidson - 6
9/1/2015 UNCLASSIFIED
1-D Ocean Model
• Waves created by wind
blowing over the ocean
surface
• Modeled ocean surface
height
– Spectral composition based
on wind speed (Pierson-
Moskowitz spectra)
– Significant wave height
based on wind speed
(Beaufort scale)
Allen, Blaylock, and Davidson - 7
9/1/2015 UNCLASSIFIED
-120 -100 -80 -60 -40 -20 0 200
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8Fully calibrated vs. empirical sea clutter distribution, wind speed = 13 knots
Power (dB)
Scale
d fre
quency
Mode, dilated mode, and standard deviation calibrated sea clutter distribution
Empirical VV polarized sea clutter distribution
Ocean Radar Return: Wind Speed = 13 knots, VV polarization
dB
• Radar return power dependent
on ocean surface slope
• Used log-normal statistics to
scale simulated radar data
Power (dB)
Allen, Blaylock, and Davidson - 8
9/1/2015 UNCLASSIFIED
Range Doppler Map
Accelerating target
Constant velocity target
Allen, Blaylock, and Davidson - 9
9/1/2015 UNCLASSIFIED
• Introduction
• Ocean Scattering Simulation
– 1-D Model
– 2-D Model
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Outline
Allen, Blaylock, and Davidson - 10
9/1/2015 UNCLASSIFIED
Quasi-Two-Dimensional Ocean
Allen, Blaylock, and Davidson - 11
9/1/2015 UNCLASSIFIED
Boat and Wake Model
• Boat modeled as a simple point target on the ocean
• Wake modeled as Kelvin wake
– Cusp wave crests
– Gives strongest radar returns
– Amplitude decay
Cusp wave
crests
http://www.goshen.edu/physix/204/gco/2slit.php
Allen, Blaylock, and Davidson - 12
9/1/2015 UNCLASSIFIED
Range-Doppler of Boat and Cusp Waves
Allen, Blaylock, and Davidson - 13
9/1/2015 UNCLASSIFIED
2-D Ocean Scattering Simulation
Allen, Blaylock, and Davidson - 14
9/1/2015 UNCLASSIFIED
RTI and RDP for a Boat With Wake on the Ocean
Allen, Blaylock, and Davidson - 15
9/1/2015 UNCLASSIFIED
• Introduction
• Ocean Scattering Simulation
– 1-D Model
– 2-D Model
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Outline
Allen, Blaylock, and Davidson - 16
9/1/2015 UNCLASSIFIED
Background: Phased Array Radar
• RF signals sent at given scan angles and return with time delay and Doppler shift
• Determine range, velocity, and angle information of boats and ocean waves
http://sitelife.aviationweek.com/ver1.0/Content/images/store/13/7/7d634054-f899-41a1-b7ca-552c8df19915.Full.jpg
Allen, Blaylock, and Davidson - 17
9/1/2015 UNCLASSIFIED
Phased Array Range Intensity Profile
Allen, Blaylock, and Davidson - 18
9/1/2015 UNCLASSIFIED
• Introduction
• Ocean Scattering Simulation
– 1-D Model
– 2-D Model
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Outline
Allen, Blaylock, and Davidson - 19
9/1/2015 UNCLASSIFIED
Processing and Computation
Radar model contains trillions of computations for each second of data
Solution:
• Algorithmic Efficiency
– Simplifying equations (assumptions)
– Use of more efficient functions or processes
• Parallelization
– pMATLAB
– Multiple cores
– LLGrid
http://en.wikipedia.org/wiki/File:IBM_Blue_Gene_P_supercomputer.jpg
Allen, Blaylock, and Davidson - 20
9/1/2015 UNCLASSIFIED
Parallelization
• Algorithm highly
parallelizable,
Speedups of up to
60x
• Scales to compute
clusters e.g. LLGrid
64, 60
32, 32
16, 16
8, 9
4, 4 2, 2 1, 1 0
10
20
30
40
50
60
70
0 10 20 30 40 50 60 70
Sp
eed
up
Number of CPUs
Speedup Measured Speedup Estimated Linear (Speedup Measured)
Allen, Blaylock, and Davidson - 21
9/1/2015 UNCLASSIFIED
• Introduction
• Ocean Scattering Simulation
– 1-D Model
– 2-D Model
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Outline
Allen, Blaylock, and Davidson - 22
9/1/2015 UNCLASSIFIED
Graphical User Interface
• User selected model
– 1-D ocean
– Quasi-2-D ocean
– Single antenna radar
– Target generation
• Input parameters
– Radar
– Ocean
– Target & wake
• Input parameter validation
Allen, Blaylock, and Davidson - 23
9/1/2015 UNCLASSIFIED
Graphical User Interface
• User selected model
– 1-D ocean
– Quasi-2-D ocean
– Single antenna radar
– Target generation
• Input parameters
– Radar
– Ocean
– Target & wake
• Input parameter validation
Allen, Blaylock, and Davidson - 24
9/1/2015 UNCLASSIFIED
• Introduction
• Ocean Scattering Simulation
– 1-D Model
– 2-D Model
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Outline
Allen, Blaylock, and Davidson - 25
9/1/2015 UNCLASSIFIED
• Improve Doppler estimation
• Implement phased array model
• Fluctuating target cross section (Swerling model)
• True 2-D ocean model
• Graphics core parallel processing
Future Work
Allen, Blaylock, and Davidson - 26
9/1/2015 UNCLASSIFIED
• Thank you to everyone that has helped our team progress with this project.
– Dennis Blejer, Lincoln Laboratory Advisor
– Edward Clancy, WPI Project Advisor
– Emily Anesta & Seth Hunter, LL-WPI Coordinators
– Jennifer Watson, Lincoln Laboratory Assistant Group Leader
– Loretta Wesley, LL Secretary
– Byun Chansup, LL Grid Support
– Scott Ehrlich, Computer Hardware and IT Support
Acknowledgements
Allen, Blaylock, and Davidson - 27
9/1/2015 UNCLASSIFIED
• Introduction
• 1-D Ocean Scattering Simulation
– Radar Processing
– 1-D Ocean Model
– Radar scattering
• 2-D Ocean Scattering Simulation
– Quasi-2-D Ocean Model
– Boat Wake Model
– Radar scattering
• Phased Array Radar Simulation
• Parallelization
• Graphical User Interface
• Future Work
Questions?
