Conference Paper

Advanced techniques and new high resolution SAR sensors for monitoring urban areas

Inst. for Electromagn. Sensing of the Environ., Nat. Reseach Council (CNR), Napoli, Italy
DOI: 10.1109/IGARSS.2010.5652309 Conference: Geoscience and Remote Sensing Symposium (IGARSS), 2010 IEEE International
Source: IEEE Xplore

ABSTRACT In the last years MultiDimensional (3D and 4D) Synthetic Aperture Radar (SAR) techniques, also known as SAR tomography and differential SAR tomography, are emerging in the field of coherent combination of multibaseline/multitemporal SAR data. With respect to the classical differential interferometric processing, these techniques improve the capability of detection and monitoring of the ground targets. Moreover they were proven to be effective in resolving the signal interference due to the layover effect, that may occur in areas with high density of scatterers located on vertical structures, such as urban areas. Beside the development of these advanced techniques the new generation of sensor, such as TerraSAR-X and COSMO-SKYMED with very high spatial resolution offer new perspectives in the imaging and monitoring of urban areas. In this paper we address the application of the SAR tomography to real spaceborne data. Particularly, we show and discuss the first results of the application of this technique to high resolution TerraSAR-X data.

Download full-text

Full-text

Available from: Xiao Xiang Zhu, Jul 03, 2015
1 Follower
 · 
128 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: To obtain the three dimensional information, which is essential for navigation in low altitude area for helicopters and other rotary wing aircrafts, a novel three-dimensional rotor synthetic aperture radar (3-D ROSAR) mode is developed. In this paper, 3-D ROSAR model is established by way of “step-hover” in the elevation direction. For this model, corresponding imaging method is also presented by the extended omega-K algorithm to focus the 3-D image. Simulation results validate the accuracy of the model and the effectiveness of the algorithm.
    Radar Conference 2013, IET International; 01/2013
  • [Show abstract] [Hide abstract]
    ABSTRACT: Techniques based on coherent combination of complex (amplitude and phase) SAR data, in particular Pol-InSAR and 3D multibaseline SAR Tomography (Tomo-SAR), can extract rich information on complex scenarios with multiple scatterers mapped in the SAR cell. However, forest scenarios are characterized by a temporal decorrelating volume canopy scatterer, and a set of related open problems exists, in particular for Tomo-SAR techniques to be applied to space monitoring of biomass. Multipass/multibaseline 4D Differential Tomography (Diff-Tomo) is a promising advancement in this field, furnishing space-time signatures of multiple scatterer dynamics in the SAR cell, in particular with urban applications. In this paper, to deal with the forest decorrelation issues in Tomo-SAR, experimental advances are presented of the original extension of Diff-Tomo methods for analyzing vegetated scenes, to extract jointly geometric and dynamic information of forest layers. The Diff-Tomo enabled functionalities are separation in the height dimension of different temporal coherence levels that are mixed (undiscriminated) in classical total coherence analyses (“Tomography of coherences”), and 3D Tomography robust to temporal decorrelation. Extended airborne P-band multipolarimetric results and phenomenological investigations are shown.
    Geoscience and Remote Sensing Symposium (IGARSS), 2013 IEEE International;; 07/2013
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this work, the staggered SAR technique is employed for high-speed platform highly-squint SAR by varying the pulse repetition interval (PRI) as a linear function of range-walk. To focus the staggered SAR data more efficiently, a low-complexity modified Omega-k algorithm is proposed based on a novel method for optimal azimuth non-uniform interpolation, avoiding zero padding in range direction for recovering range cell migration (RCM) and saving in both data storage and computational load. An approximate model on continuous PRI variation with respect to sliding receive-window is employed in the proposed algorithm, leaving a residual phase error only due to the effect of a time-varying Doppler phase caused by staggered SAR. Then, azimuth non-uniform interpolation (ANI) at baseband is carried out to compensate the azimuth non-uniform sampling (ANS) effect resulting from continuous PRI variation, which is further followed by the modified Omega-k algorithm. The proposed algorithm has a significantly lower computational complexity, but with an equally effective imaging performance, as shown in our simulation results.
    Sensors 02/2015; 15(2):3750-65. DOI:10.3390/s150203750 · 2.05 Impact Factor