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Alessio Di SimoneTutor: Daniele Riccio
XXIX Cycle - I year presentation
Information extraction from a single SAR image
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My personal background• MSc in Telecommunications Engineering – Università di Napoli Federico II • Fellowship – MIUR – FSG research program "Sistemi di telecomunicazione innovativi a
larga banda anche con impiego di satelliti per utenze differenziate in materia di sicurezza, prevenzione e intervento in caso di catastrofi naturali”
Alessio Di Simone
DIETI
Electromagnetics Research Group
Remote Sensing Research Group
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Rationale: SAR images dependencies
Alessio Di Simone
SAR Image dependencies
Electromagnetic parameters Geometric parameters
Surface parameters • Dielectric constant (complex)
• Roughness• Topography (slopes)
Sensor parameters • Polarization• Operating frequency
• Look angle• Resolution
Known parameters
Unknown parameters
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Problem Statement: Well-posed?
𝐼=𝐼 (ε 𝑟 , σ ,𝐻 ,𝑇 , ϑ )
Alessio Di Simone
Ill-posedness
Cannot be removed (intrinsic property of the problem) Could be circumvented but…
Need for an adequate direct model
One equation, many unknowns
Objective Retrieving information from a single SAR image through mathematical and physical (electromagnetic) models
Interest Limited availability of resources, e.g., space missions, developing countries
: Relative permittivity: Electrical conductivity: Hurst coefficient: Topothesy: Local incidence angle
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(Fractal) Direct Model
Alessio Di Simone
Natural Surface Model (fBm)
Scattering Model (SPM)𝜎𝑚𝑛0 =2𝜋 8𝑘4𝑐𝑜𝑠4 𝜃|𝛽𝑚𝑛|
2 𝑆0
(2𝑘sin 𝜃 )2+2𝐻
Pr {𝑧 (𝑥 , 𝑦 )−𝑧 (𝑥 ′ , 𝑦 ′ )<𝜁 }= 1
√2𝜋 𝑇 (1−𝐻 )𝜏𝐻 ∫−∞
𝜁
exp(− 𝜁2
2𝑇 2 (1−𝐻)𝜏2𝐻 )𝑑𝜁
SAR Image Model
T: TopothesyH: Hurst coefficient
Backscattering coefficient: Propagation constant: Local incidence angle: Reflection coefficient: Spectral amplitude
: Calibration constant: Azimuth SAR resolution: Slant range resolution
𝐼=𝐺𝜎𝑚𝑛0
sin 𝜃𝛥𝑥 𝛥𝑟
𝐼=𝐺𝛥𝑥𝛥𝑟 2𝜋 8𝑘4𝑆0|𝛽𝑚𝑛|2 𝑐𝑜𝑠4 𝜃
(2𝑘 )2+2𝐻 (sin 𝜃 )3+ 2𝐻
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Sensitivity Analysis
Alessio Di Simone
SAR image greatest dependency is on the local incidence angle
Nor
mal
ized
SAR
Imag
e In
tens
ity
Dielectric constant Electrical conductivity [S/m]
Hurst coefficient Topothesy [m]
Incidence angle [degree]
Nor
mal
ized
SAR
Imag
e In
tens
ityN
orm
alize
d SA
R Im
age
Inte
nsity
Nor
mal
ized
SAR
Imag
e In
tens
ity
Incidence angle [degree]Incidence angle [degree]
Incidence angle [degree]
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Inversion Procedure
• Electromagnetic homogeneity of the surface, i.e., constant relative permettivity and electrical conductivity.
• Scale-invariant roughness, i.e., constant Hurst exponent and topothesy at any scale.
Alessio Di Simone
•Small slope regime, i.e., gentle topography.Only for simplifying the inversion procedure
Direct model linearization against local slopes• No dependency on azimuth slopes
Local slopes can be estimated
Hypotheses
Sub-hypothesis
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High-Level Products – I
• SAR Despeckling (Non Local Means Approach)
Alessio Di Simone
Original SAR image Despeckled image
No resolution degradation
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High-Level Products – II
• Local Incidence Angle Map • Digital Elevation Model
Alessio Di Simone
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Next years…• Research activities:
– Complete Model, rather than the linearized one.– Incidence angle estimation, rather than local slopes.– Further information retrieving.
• Training activities:
Alessio Di Simone
Credits year 1 Credits year 2 Credits year 3
1 2 3 4 5 6
Estimated
bimonth
bimonth
bimonth
bimonth
bimonth
bimonth
Summary Check
Estimated Check
Estimated Check Total
Modules 30 3 3 6 3 10 25 20-40 18 10-20 6 0-10 49
Seminars 8 1,2 0,9 0 1 1 0,9 5 5-10 8 5-10 5 0-10 18
Research 22 7 5 7 3 6 2 30 10-35 34 30-45 49 40-60 113
60 8,2 8,9 10 10 10 12,9 60 60 60 180
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List of publicationsJournals
1. Di Martino, G., Di Simone, A., Iodice, A., Riccio, D., “Shape from Shading and SAR Images,” IEEE Trans. Geosci. and Remote Sens.,
(resubmitted).
Conferences
2. Di Simone, A., Riccio, D., “A New Perspective in Shape from Shading from SAR Images”, IEEE Graduate of the Last Decade (GOLD)
Conference, Berlin, June, 5-6, 2014.
3. Di Martino, G., Di Simone, A., Iodice, A., Riccio, D., and Ruello, G., “On shape from Shading and SAR Images: an Overview and a New
Perspective,” International Geoscience and Remote Sensing Symposium (IGARSS), Quebec City, July, 13-18, 2014.
4. Di Martino, G., Di Simone, A., Iodice, A., Riccio, D., and Ruello, G., “Polarimetry and Shape from Shading,” POLinSAR Conference,
Frascati, January, 26-30, 2015. (accepted)
5. Di Martino, G., Di Simone, A., Iodice, A., Riccio, D., and Ruello, G., “SAR Shape from Shading in Suburban Areas,” Joint Urban
Remote Sensing Event (JURSE), Lausanne, March, 30 – April 1, 2015. (accepted)
6. Di Martino, G., Di Simone, A., Iodice, A., Riccio, D., and Ruello, G., “Electromagnetic Model for SAR Shape from Shading,” RiNEm, pp.
277-280, Padova, September, 15-18, 2014.
Alessio Di Simone