Polarimetric Scattering Research Articles

S-Band Polarimetric Radar Scattering Measurement from Different Random Rough Surface

S-Band Polarimetric Radar Scattering Measurement from Different Random Rough Surface

Study of Physical Phenomena of Vegetation Using Polarimetric Scattering indices and Entropy

A polarimetric model has been developed to study the temporal growth of different vegetation canopies, and their architecture. Eigen decomposition and coherency matrices are analyzed for completely polarimetric Radarsat-2 data. Polarimetric indices have been formulated using co and cross polarized backscattering coefficients, eigen values and eigen vectors. The polarization indices are used to completely understand the difference between polarized scattering signatures of vegetation in HH and VV polarizations. In this study, two decomposition techniques have been used like Freeman-Durden and H/A/α and their volume scattering and entropy components in conjunction with co and cross polarized indices are analyzed. This qualitative evaluation of vegetation parameters and growth stage are found to work better with polarimetric complex SAR data rather than using amplitude imagery.

A Novel Fully Polarimetric Scattering Center Extraction Method Based on Ofdm Radar Signal

Target high resolution and fully polarimetric information is of important application in such fields as remote sensing, target recognition and so on. Simultaneous polarization measurement scheme is one new method to obtain target polarization scattering matrix (PSM), in stead of traditional alternative polarization measurement scheme. Based on its basic principle, fully polarimetric OFDM waveform is designed to extract target fully polarimetric scattering centers. After establishing the received data model, the two-dimensional polarimetric Multiple Signal Classification (2D P-MUSIC) algorithm is used to extract target scattering characteristic. Simulations are performed to verify the effectiveness of this waveform and its corresponding signal processing.

A General Characterization for Polarimetric Scattering From Vegetation Canopies

Current polarimetric model-based decomposition techniques are limited to specific types of vegetation because of their assumptions about the volume scattering component. In this paper, we propose a generalized probability density function based on the nth power of a cosine-squared function. This distribution is completely characterized by two parameters; a mean orientation angle and the power of the cosine-squared function. We show that the underlying randomness of the distribution is only a function of the power of the cosine-squared function. We then derive the average covariance matrix for various different elementary scatterers showing that the result has a very simple analytical form suitable for use in model-based decomposition schemes.

Assessment of Polarimetric SAR Interferometry for Improving Ship Classification based on Simulated Data.

This paper uses a complete and realistic SAR simulation processing chain, GRECOSAR, to study the potentialities of Polarimetric SAR Interferometry (POLInSAR) in the development of new classification methods for ships. Its high processing efficiency and scenario flexibility have allowed to develop exhaustive scattering studies. The results have revealed, first, vessels' geometries can be described by specific combinations of Permanent Polarimetric Scatterers (PePS) and, second, each type of vessel could be characterized by a particular spatial and polarimetric distribution of PePS. Such properties have been recently exploited to propose a new Vessel Classification Algorithm (VCA) working with POLInSAR data, which, according to several simulation tests, may provide promising performance in real scenarios. Along the paper, explanation of the main steps summarizing the whole research activity carried out with ships and GRECOSAR are provided as well as examples of the main results and VCA validation tests. Special attention will be devoted to the new improvements achieved, which are related to simulations processing a new and highly realistic sea surface model. The paper will show that, for POLInSAR data with fine resolution, VCA can help to classify ships with notable robustness under diverse and adverse observation conditions.

Conservative Polarimetric Scatterers and Their Role in Incorrect Extensions of the Cameron Decomposition

The properties of symmetric polarimetric scatterer scattering matrices are examined. It is shown that the unambiguous rotation angle for conservative symmetric polarimetric scatterers is the interval (-pi/4,+pi/4] as compared with (-pi/2,+pi/2] for nonconservative symmetric scatterers. Errors relating to the Cameron decomposition, which are recently introduced into the literature, are discussed. It is demonstrated that these errors arise from a faulty symmetric scatterer scattering matrix distance measure. This, in turn, leads to an improper mapping of the symmetric scatterer unit disk to a hemisphere. The correct mapping of the symmetric scatterer unit disk to the symmetric scatterer unit sphere is described

Polarimetric Scattering from a Layer of Spatially-Oriented Metamaterial Small Spheroids

The complex scattering amplitude functions of a small metamaterial spheroid are derived under Rayleigh approximation. | fvv | and | fhh | of dielectric spheroid are symmetric along incident direction, while metamaterial spheroid along spheroid’s axis. The Mueller matrix for polarimetric scattering of a layer of random metamaterial small spheroids is constructed. Compared with dispersive FR-4 spheroids, σhh and σvv of metamaterial vary remarkably with frequency due to constitutive dispersion of e(ω) and � (ω), and take a peak at its resonance frequency. The σhh and σvv and polarizability degree ms, are simulated for a layer of nonuniformly oriented metamaterial spheroids under the illumination of an elliptically polarized plane wave. The scattering of metamaterial particles exhibits asymmetric directivity.

Polarimetric Scattering From Two-Layered Two-Dimensional Random Rough Surfaces With and Without Buried Objects

A three-dimensional polarimetric analysis of the two-layered rough ground with and without buried objects is investigated here. A rigorous electromagnetic surface integral-equation-based model is used in this analysis. The statistical average of the polarimetric scattering matrix elements is computed based on the Monte Carlo simulations for both the vertically and horizontally polarized incident waves. The results show a significant impact on the scattered intensities due to the two-layer nature of the ground. However, these intensities show almost no difference between the ground signature with or without the object. On the other hand, the statistical average of the covariance matrix elements shows a distinct difference between these two signatures despite the small size of the buried object.

Image Simulation of High Resolution Radar for Fully Polarimetric Scattering from Heterogeneous Canopy Surface

Image Simulation of High Resolution Radar for Fully Polarimetric Scattering from Heterogeneous Canopy Surface