Radar activities CISS

1
Radar activities _at_ CISS
Dr Ir Xavier Neyt Cdt Dr Ir Marijke
Vandewal Royal Military Academy Signal and Image
Centre Brussels Belgium
2
Radar activities _at_ CISS
Medium
Object
Signal Processing
Post Processing
Image Processing
Sensor
300 MHz 300 GHz
THz waves or T-rays
3
Research Axes
Software Defined Radar
SAR processing
Post- processing
Image processing
Medium
Object
Segmentation
Polarimetry
Simulation
Fusion
Interferometry
Motion Comp.
Sensor
Classification
PolInSar
High resolution
Multiaspect
Bistatic
Tomography
Scattering
Antennas
MTI
Tracking
Bistatic
Passive.
Multistatic
Adaptive
VISION Signal processing to improve system
performance
4
SAR-UAV Performance
Platform Motion Errors
Targets Background
Raw Data Generator
?
Image Quality Analysis
SAR Processor
5
SAR-UAV Performance
Effects of uncontrolled platform motion on SAR
images
Across-track acceleration error
Straight flight path
SAR HALE UAV
6
SAR-UAV Performance
Effects of uncontrolled platform motion on SAR
images
Straight flight path
Across-track vibration error
SAR TUAV
7
Motion Compensation
Motion compensation for SAR images
Low Frequency Error
Synthetic Aperture
Z
Position error Velocity error Acceleration error
?
?
h
High Frequency Error
Vibrations
X
Point Target
Y
8
Motion Compensation
Motion compensation for SAR images

• Methods
• Using exact aircraft position (INS-GPS)
• Using autofocus method
• Results
• Autofocus method

9
SAR for NDT applications

• Non-Destructive Testing (NDT) techniques
• see-through capacity
• high spatial resolution (range azimuth)

• High-frequency - SAR for composite materials
• 50-700 GHz
• 3D Synthetic aperture processing

10
SAR for NDT applications
2D Scanning geometry
Expected performance (resolution)
11
Through the wall imaging

• Using a rail-based radar
• Challenge determine wall characteristics
• Thickness, material (dielectrical constant)

Apparent movement of the point target for
different parameters
Radar image of a point target
12
Research Axes
Software Defined Radar
SAR processing
Post- processing
Image processing
Medium
Object
Segmentation
Polarimetry
Simulation
Fusion
Interferometry
Motion Comp.
Sensor
Classification
PolInSar
High resolution
Multiaspect
Bistatic
Tomography
Scattering
Antennas
MTI
Tracking
Bistatic
Passive.
Multistatic
Adaptive
VISION Signal processing to improve system
performance
13
Scatterometry
ERS-2 Gyroscopes malfunction

• ERS-2 SAR satellite
• 3 axis stabilized
• Gyroscopes malfunction
• Unknown yaw angle
• Estimation
• From Doppler frequency shift
• Adapt processing chain
• Calibration

14
Scatterometry
ERS-2 Gyroscopes malfunction
Doppler frequency
Doppler frequency
New processing chain
Gyroscopes malfunction
Satellite launch
Nominal operation
Inadapted processing
Nominal performance
5 year
2.5 year
2 year
15
Scatterometry
First cyclone image
16
Scatterometry

• Cross-calibration ERS METOP
• Compare measurements
• From 2 space-based radars
• Determine intersection
• Same position
• Same time!
• Compensate incidence angle effect

17
Space-Time Adaptive Processing

• Moving target detection
• Static radar
• Target / Clutter separation
• Based on the Doppler frequency

18
Space-Time Adaptive Processing

• Ground Moving Target Indication
• Moving radar
• Target / Clutter separation
• Cannot be based on the Doppler frequency

19
Space-Time Adaptive Processing

• STAP add the direction of arrival (DOA)
• Moving radar
• Target / Clutter separation
• based on the Doppler frequency and DOA

20
Passive radar

• Use emitters of opportunity
• GSM base stations
• Used to track (ground) moving targets
• Challenge target / clutter signal separation

21
Passive radar Results

• Tx GSM base station
• Cooperative target
• car (fd -39 Hz)

240m
162
No filtering Clutter signal dominates
After filtering Target(s) signal dominates
Measurements performed in collaboration with
Ecole de lAir and ONERA Salon-de-Provence
22
Passive radar Next step
Transmitter
Goal produce a SAR image of the ground
(Envisat, ERS,GPS, Gallileo)
Direct-path signal
Receiver
Reflected signal
23
Space Situational Awareness

• Awareness of
• orbit population
• Detection, Reconnaissance
• the space environment
• Debris, Space weather, Meteroids
• 24th Jul 96 French microsatellite CERISE striked
  by space debris
• threats to/by orbit population
• Re-entries, Collisions, Explosions, Weapons
• Jan 07 China blew up one of its own satellites
  using a laser

Surveillance
24
Space Situational Awareness

• Imaging radars TIRA
• Take images of satellites
• Detect and track radar Graves
• Bistatic CW radar

Involvment of RMA contribution to system
specification
25
Optimum Trade-Off
Signal processing algorithms ? Feasible hardware
Goal

• Multi-purpose military radar systems
• Intelligent signal processing and/or generation
• Adaptive processing
• Knowledge-based processing
• Cognitive processing

Pulse compression radar jammer (X-band)
26
Acknowledgements

• RMA participants of the presented research
• P. Decroix, P. Pettiaux, E. Cuvelier,
• M. Desmet, N. Manise, T. Debatty,
• V. Kubica, M. Kubica, A. Elyouncha,
• R. Heremans, P. Druyts, F. Lapierre,
• J.P. Salmon

27
Research Axes
Software Defined Radar
SAR processing
Post- processing
Image processing
Medium
Object
Segmentation
Polarimetry
Simulation
Fusion
Interferometry
Motion Comp.
Sensor
Classification
PolInSar
High resolution
Multiaspect
Bistatic
Tomography
Scattering
Antennas
MTI
Tracking
Bistatic
Passive.
Multistatic
Adaptive
VISION Signal processing to improve system
performance
28
Backup slides
29
Collaborations