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Accuracy and efficiency are two important objectives of modeling ground penetrating radar (GPR) signal. Achieving both together is a driving factor for advanced research in the state of art for GPR community. Full wave model (FWM) promises great accuracy to detect layered media. However time efficiency of FWM is poor compared to other simplified models. This work presents a new plane wave model (PWM)...
RFID collision is a main challenge imposed by radio wave links shared among a reader and many tags in interrogation zone. Collision is a power-consuming event that reduces the performance of RFID systems. Low power consumption strategy would ensure longer operational life of tags and reader by battery-powered supply. Application of several anti-collision algorithms makes it possible for reader to...
This paper proposes to study a novel problem, discovering a Smallest Unique Subgraph (SUS) for any node of interest specified by user in a heterogeneous social network. The rationale of the SUS problem lies in how a person is different from any others in a social network, and how to represent the identity of a person using her surrounding relational structure in a social network. To deal with the...
A new approach to nanoscale MOSFETs electrical characteristics calculating, the essence of which is the use of adjustment factors, as well as parameter values of classic driftdiffusion models, which would effectively take into account the quantum-mechanical transport mechanisms is proposed. A modified direct search method of drift-diffusion model optimization for MOSFET with a 90 nm channel length...
Because of the local deformation of SAR images Registration of Multiband SAR images with high accuracy(sub-pixel accuracy) is a very difficult problem. This paper present an automatic Coarse-to-Precise(global-to-local) subpixel registration framework to track it. Firstly, affine SIFT method is adopted to get affine parameter of global transformation between registered images. After global registration,...
Similar to the conventional synthetic aperture radar (SAR) imaging processing, the estimation of Doppler chirp rate is one key problem for the multi-channel in azimuth high-resolution and wide-swath (HRWS) SAR system. At the same time, the accurate estimation of baseline in azimuth is also important for the reconstruction of ambiguity-free Doppler spectrum. In this paper, based on the Map Drift algorithm...
Traditional pixel-based change detection methods are undertaken using the pixel as the research unit. These methods may give high false alarm rate and broken areas, because they don't use semantic information. In order to solve this problem, we present a novel change detection method which is based on radon transform and super-pixel segmentation. First, radon transform is used to achieve a stable...
Elevation measurement using Synthetic Aperture Radar (SAR) is one of crucial applications in remote sensing, since the use of SAR in elevation measurement makes it possible to measure a wide range of planar area. Most of conventional methods need Ground Control Points (GCPs) to achieve accurate 3D measurement, where GCP acquisition is a time-consuming and cost-intensive task. Addressing the above...
This paper presents a new concept of Space-Airborne Bi-Static Linear Array SAR (SA-BiLASAR) imaging using array antenna, which inherited the advantages of conventional linear array antenna 3-D SAR and Bi-Static SAR. Firstly, the geometrical model and the signal model are established. Secondly, a time domain back projection imaging algorithm is presented for SA-BiLASAR data processing. In the end,...
A modified chirp scaling (CS) algorithm for processing spaceborne squinted sliding spotlight synthetic aperture radar (SAR) data is proposed in this paper. For squinted sliding spotlight mode, both the squint angle and azimuth beam steering make the spectral aliasing in azimuth. To solve this problem, the linear range cell migration correction (LRCM) and De-rotation are adopted firstly. Then a modified...
Conditional random fields (CRF) model is suitable for image segmentation because this model directly defines the posterior distribution as a Gibbs field and allows one to capture the dependencies of the observed data. However, this model has a limited ability to capture the high-order label dependencies with only the pairwise potential being constructed generally. Moreover, for synthetic aperture...
Synthetic Aperture Rader (SAR), with all-weather and all-time imaging capabilities, provides a stable data resource for environmental monitoring. In water related applications, obtaining precise water areas from SAR data is essential. This paper presents a high accuracy water extraction scheme based on Object-Oriented technique. First, a watershed segmentation is used for preserve waterlines. Then,...
This paper presents here aims at the retrieval of sea surface velocity during tropical clones using RADARSAT-1 ScanSAR Doppler centroid measurements. The sea surface velocity can be estimated by comparing Doppler shift anomalies between predicted and estimated Doppler centroids. The predicted Doppler centroid, defined as the Doppler centroid assuming that the target is not moving, is calculated based...
Inverse Synthetic Aperture Radar (ISAR) has the function of remote imaging with non-cooperative targets. It has important value in application of the space target surveillance, recognition and cataloging, and satellite fault diagnosis. This paper describes multi-dimensional ISAR imaging technology in detail. Research results of real-time ISAR imaging with mono-static and multi-polarization, and bi-static...
GF-3 is the Chinese Synthetic Aperture Radar (SAR) satellite mission with scientific and commercial applications, which will be launched in 2016. It allows operation in Stripmap, ScanSAR and Sliding Spotlight modes in different polarizations. The Sliding Spotlight Mode is a new imaging mode widely used in high resolution SAR imaging. Considering the imaging processing model, we have modified the equivalent...
In this paper, we describe a simple method for SAR image synthesis of a realistic target model using the general purpose EM simulator like FEKO and demonstrate the steps by processing the simulated SAR raw data with chirp-scaling algorithm (CSA), which is one of the most widely used SAR image formation algorithms. This method can benefit us many advantages like performance evaluation for target detection,...
For synthetic aperture radar(SAR) imaging of ship targets, it's difficult to generate high quality images because their motion characteristics are blind in most cases. Aiming at this problem, this paper presents a processing scheme for estimating the radial velocity based on the digital spotlight processing. This method is implemented after the coarse-resolution wide area image is obtained. Then the...
It has been validated that the cross-polarized scattering (HV) is caused not only by vegetation but also by rotated dihedrals, then the orientation angle of the rotated dihedrals can be obtained by minimizing the cross-polarized scattering component of covariance matrix. Therefore, this paper presents an improvement of multiple-component scattering model of rotated covariance matrix for Polarimetric...
Advanced synthetic aperture radar (SAR) imaging systems provide high-resolution images for a number of applications in maritime surveillance. However, the relative movement between the radar and the moving target will cause defocusing phenomenon, leading to decreasing image resolution. In this paper, we adopt an existing approach to refocus ship targets starting from formed Single Look Complex (SLC)...
An efficient approach to achieve ground moving target indication (GMTI) for synthetic aperture radar (SAR) is to use the Monopulse-SAR system. This paper examines the statistics of complex monopulse ratio (CMR) for SAR/GMTI model when complex Gaussian clutter-plus-noise is considered. The two dimensional probability density function (pdf) of CMR is analyzed in detail. An automatic constant false-alarm...
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