Airborne Holographic SAR Tomography at L- and P-band O. Ponce, A. - - PowerPoint PPT Presentation

▶
airborne holographic sar tomography at l and p band
SMART_READER_LITE
LIVE PREVIEW

Airborne Holographic SAR Tomography at L- and P-band O. Ponce, A. - - PowerPoint PPT Presentation

Mar 10, 2024 37 likes •378 views

Airborne Holographic SAR Tomography at L- and P-band O. Ponce, A. Reigber and A. Moreira. Microwaves and Radar Institute (HR), German Aerospace Center (DLR). 1 Outline Introduction to 3-D SAR Holographic SAR Tomography (HoloSAR)

slide-1
SLIDE 1

1

Airborne Holographic SAR Tomography at L- and P-band

  • O. Ponce, A. Reigber and A. Moreira.

Microwaves and Radar Institute (HR), German Aerospace Center (DLR).

slide-2
SLIDE 2

2

Outline

  • Introduction to 3-D SAR
  • Holographic SAR Tomography (HoloSAR)
  • Theory and Imaging Approaches
  • Experimental Realizations
  • Conclusions
slide-3
SLIDE 3

3

Introduction – 3-D SAR Imaging

SAR Interferometry (InSAR) SAR Tomography (SARTom)

y z x n r

h

1 2

B

y z x n r

h

1 2 N . . .

slide-4
SLIDE 4

4

Introduction – 3-D SAR Imaging

SAR Interferometry (InSAR) SAR Tomography (SARTom)

Digital Elevation Model (DEM) of Iceland, 2011. Retrieved Information:

  • Height
  • Single aspect angle

Retrieved Information:

  • Complex reflectivity
  • Resolution in
  • Single aspect angle
slide-5
SLIDE 5

5

Introduction – 3-D SAR Imaging

Circular SAR (CSAR) Holographic SAR Tomography (HoloSAR)

y z x

h

n r y z x

h

1 2 N . . .

n r

slide-6
SLIDE 6

6

Introduction – 3-D SAR Imaging

Circular SAR (CSAR) Holographic SAR Tomography (HoloSAR)

Retrieved Information:

  • Complex reflectivity
  • Resolution in
  • Multiple aspect angles
  • Sub- resolution in ,
  • Low resolution in

Retrieved Information:

  • Complex reflectivity
  • Resolution in
  • Multiple aspect angles
  • Sub- resolution in ,
  • High resolution in

Impulse Response Function - Luneburg Lens Impulse Response Function - Luneburg Lens

slide-7
SLIDE 7

7

Introduction – Linear SAR VS Circular SAR

Stripmap SAR Circular SAR

slide-8
SLIDE 8

8 Circular SAR Stripmap SAR

Experimental Realizations - Circular SAR – L-band

Pauli basis, Coherent imaging, 500 m x 500 m, 0.06 m by 0.06 m sampling E‐SAR L‐Band, bandwidth 95MHz

slide-9
SLIDE 9

9

Theory on HoloSAR – Impulse Response Function

Reigber, et al, First demonstration of Airborne SAR Tomography using Multi-baseline L-band data, IEEE TGRS, 2000.

  • Resolution
  • Ambiguities

Gatelli, et al, The wavenumber shift in SAR interferometry, IEEE TGRS, 1994.

slide-10
SLIDE 10

10

Theory on HoloSAR – Impulse Response Function

  • IRF
  • , IRF
  • Bandwidth enhancement
  • F. Gatelli, et al, The wavenumber shift in SAR interferometry, IEEE TGRS, 1994.
slide-11
SLIDE 11

11

Spectrum of HoloSAR - k space

slide-12
SLIDE 12

12 19 tracks, ∆ 12 m 3 tracks, ∆ 150 m 1 track

Theory on HoloSAR – Impulse Response Function

slide-13
SLIDE 13

13

Theory on HoloSAR – Imaging Approaches

1 2 3

  • O. Ponce, et al, Analysis and optimisation of multi-circular SAR for fully polarimetric holographic tomography over forested areas, IGARSS 2013.
  • O. Ponce, et al, Fully-Polarimetric High-Resolution 3-D imaging with CSAR at L-band, TGRS, 2014, in press.
  • O. Ponce, et al, Polarimetric 3-D Reconstruction from Multi-Circular SAR at P-band, GRSL 2014 .
slide-14
SLIDE 14

14

Theory on HoloSAR – Imaging Approaches

1 2 3

Generalized Likelihood Ratio (GLRT) Incoherent Addition Coherent Addition - Fourier Compressive Sensing (CS) Holographic SAR Tomogram

. . . . . .

  • O. Ponce, et al, Analysis and optimisation of multi-circular SAR for fully polarimetric holographic tomography over forested areas, IGARSS 2013.
  • O. Ponce, et al, Fully-Polarimetric High-Resolution 3-D imaging with CSAR at L-band, TGRS, 2014, in press.
  • O. Ponce, et al, Polarimetric 3-D Reconstruction from Multi-Circular SAR at P-band, GRSL 2014 .

Beamforming (BF)

. . .

slide-15
SLIDE 15

15

Experimental Realizations – HoloSAR at P-band

Campaign Polarisations HH, HV, VH, VV Central Frequency P‐Band Chirp Bandwidth 20 MHz PRF 500 Hz Circular passes 7

  • Max. Baseline [m]

110 m Radius avg. 3800 m Region Vordemwald, CH. 3-D HoloSAR Tracks

F-SAR System

slide-16
SLIDE 16

16

Experimental Realizations – HoloSAR at P-band

Pauli basis, . km diameter, . m by . m sampling

slide-17
SLIDE 17

17

Forested area - tracks – Span – , slices

Subaperture, Fourier + Incoherent Fourier + Incoherent

slide-18
SLIDE 18

18

Forested area - tracks – Span – , slices

CS + Incoherent Fourier + Incoherent

slide-19
SLIDE 19

19

Forested area - tracks – Span – , slices

CS + Incoherent Fourier + Incoherent

slide-20
SLIDE 20

20

Forested area - tracks – Fourier + Incoherent – , slices

Lexicographic (red line LIDAR) Span

slide-21
SLIDE 21

21

Forested area - tracks – CS + Incoherent – , slices

Lexicographic (red line LIDAR) Span

slide-22
SLIDE 22

22

Forested area - tracks – CS + Incoherent – 3-D View

slide-23
SLIDE 23

23

Experimental Realizations – HoloSAR at L-band

Campaign Polarisations HH, HV, VH, VV Central Frequency L‐Band Chirp Bandwidth 50 MHz PRF 500 Hz Circular passes 19

  • Max. Baseline [m]

285 m Radius avg. 3700 m Region Kaufbeuren, DE. 3-D HoloSAR Tracks

F-SAR System

slide-24
SLIDE 24

24

Experimental Realizations – HoloSAR at L-band

Pauli basis, . km diameter, . m by . m sampling 1) 15 x 15 x 50 m, 2) 300 x 300 x 50 m

slide-25
SLIDE 25

25 19 tracks, ∆ 12 m 3 tracks, ∆ 150 m

Experimental Realizations – HoloSAR at L-band

1 track

21

Single Tree – Pauli basis – 15 x 15 x 50 m

slide-26
SLIDE 26

26

21

Compressive Sensing + GLRT Compressive Sensing + Incoherent Coherent

Experimental Realizations – HoloSAR at L-band

Forested Area – Tracks - Pauli basis

slide-27
SLIDE 27

27

Forested area - tracks – Pauli - 2-D slices – . m

Compressive Sensing + GLRT Compressive Sensing + Incoherent Coherent * red line  LIDAR

slide-28
SLIDE 28

28

Forested area - tracks – Pauli - 2-D slices – . m

Compressive Sensing + GLRT Compressive Sensing + Incoherent Coherent

slide-29
SLIDE 29

29

Forested area – Pauli - tracks – 2-D slices - / m

Coherent Compressive Sensing + Incoherent Compressive Sensing + GLRT

slide-30
SLIDE 30

30

Forested area – Pauli - tracks – 3-D view

Compressive Sensing + Incoherent 27

slide-31
SLIDE 31

31

Conclusions

  • HoloSAR offers unique means to get the full 3-D backscattering over 360°.
  • Improvement of the effective BW by taking into account the several circular

passes with vertical or horizontal separation

  • Theory is validated with Airborne acquisitions at L- and P-band over forests.
  • HoloSAR can be used as a powerful tool to measure biophisical parameters,

and to reduce uncertainties of conventional 3-D SAR modes

  • Potential for Future Earth Observation Space Missions
slide-32
SLIDE 32

32

L‐Band image with 6 cm sampling

What are you seeing here?

slide-33
SLIDE 33

33

DLR’s airborne SAR – L‐Band quad pol

Pauli basis, 1.8 km diameter, 0.06 m by 0.06 m sampling 1 2 3 4 1 2 3 4

slide-34
SLIDE 34

34

Thanks for your attention!