In the corner reflector jamming scenario, ship target and array have different degrees of defocusing in synthetic aperture radar (SAR) image due to their complex motions, which is unfavorable subsequent recognition. this manuscript, we propose an imaging method for marine targets based on time–frequency analysis with modified Clean technique. Firstly, motion models are established, characteristics Doppler parameter distribution analyzed. Then, Chirp Rate–Quadratic Rate Distribution (CR-QCRD)...

Ship motions during long coherent processing interval (CPI) have six degrees of freedom, and the oscillatory are roughly periodical. The traditional ship imaging methods usually use a short time to form an image, while image quality may suffer from low resolution, poor signal-to-noise ratio (SNR), scatter scintillation. Using longer CPI generate improve but, however, largely increase focusing difficulty. In this article, we investigate challenges ships with CPI. Through analyzing relative...

Due to the limited information of two-dimensional (2D) radar images, study three-dimensional (3D) image reconstruction has received significant attention. However, target attitude obtained by existing 3D methods is unknown. In addition, using a single perspective, one can only get result simple target. For complex target, due occlusion and scattering characteristics, from perspective limited. To tackle above two problems, this paper proposes new method for multi-perspective instantaneous...

Inverse synthetic aperture radar (ISAR) imaging has been widely developed and applied in many applications, such as, target recognition, autopilot seaport ship surveillance, etc. However, low signal-to-noise ratio (SNR) environments may impede conventional range profiles-based translational motion compensation (TMC), causing image degradation. In this paper, a novel method combining profiles phase is proposed which utilizes two-dimensional (2-D) coherent accumulation to overcome the SNR...

Spectrum analysis (SA) plays an important role in radar signal processing, especially imaging algorithm design. Because it is usually hard to obtain the analytical expression of spectrum by Fourier integral directly, principle stationary phase (POSP)-based SA applied approximate this integral. However, POSP requires vary rapidly, which not case circular synthetic aperture (SAR) and turntable inverse SAR (ISAR). To solve problem, a new method based on time-frequency reversion (TFRSA)...

In a low signal-to-noise ratio (SNR) environment, conventional range profiles-based motion compensation (MoCo) methods become inapplicable for inverse synthetic aperture radar (ISAR) imaging. this article, novel method profile alignment along with phase adjustment is proposed. The applied in the uncompressed history domain without need prominent point. Motion errors are estimated from map using only fast Fourier transform (FFT) and Hadamard multiplication operations, making suitable...

This manuscript presents a novel scheme to achieve high-resolution laser-radar ranging with small sample number under low signal-to-noise ratio (SNR) conditions. To reduce the number, Restricted Isometry Property-based optimal multi-channel coprime-sampling (RIP-OMCS) strategy is established. In RIP-OMCS strategy, data collected across multiple channels very rates can record accurate range information on each target. Further, asynchronous problem caused by channel sampling-time errors...

Combining inverse projection and vote accumulation methods, we propose a novel 3D geometric reconstruction method based on synthetic aperture radar (ISAR) image sequence for triaxially stabilized space targets. Considering that the translation of target results in large angular rotation line sight (LOS) an attitude adjustment itself, relationship between imaging plane is constructed first. Subsequently, perform dominant points extracted from each to determine location candidate scatterers...

A suitable regularization parameter plays an important role in sparse ISAR imaging algorithms. With a proper parameter, the quality of images improves. In this paper, Homotopy re-weighted ℓ1-norm minimization is applied to imaging. This method able choose accurate for each point image with high efficiency. As result, results processed by contain more details target and less artificial points. Both simulated real data experiments validate feasibility proposed method.

A retinal prosthesis is designed to help the blind obtain some sight. It consists of an external part and internal part. The made up a camera, image processor RF transmitter. receiver, implant chip microelectrode.Currently, number microelectrodes in hundreds, we do not know mechanism for using electrode stimulate optic nerve. simple hypothesis that pixels correspond electrode. images captured by camera should be processed suitable strategies stimulation from Thus, it question how important...

The refraction, dispersion and reflection will occur when electromagnetic wave passing through the ionosphere, which affects human activities of aerospace investigation earth environmental remote sensing severely. total electron content (TEC) is a key to evaluate ionosphere. This paper proposes novel ionospheric TEC estimation method base on L-band inverse synthetic aperture radar (ISAR) signal processing, two-step strategy. coarse first step achieved by coherently integrated modified cubic...

In this paper, we present a multichannel superresolution radar imaging (MSRI) approach. Our approach for extracting the two-dimensional (2-D) scattering center model is based on combination of cosine-modulated filter bank with perfect reconstruction condition (PR-CMFB) and TLS-ESPRIT matrix enhancement (TLS-ESPRIT-ME) method. The basic idea underlying proposed that analysis banks are first used to implement decomposition signal in frequency-aspect domain, synthesis then recombine decomposed...

Three-dimensional (3-D) radar imaging is an important task underpinning many applications that seek target detection, localization, and classification. However, traditional 3-D computationally cumbersome needs a large memory space to store the cubic data matrix. These challenges have hindered development limited its applications. Owing sparsity of image typical targets, size could be significantly reduced by exploiting compressive sensing sparse reconstruction techniques. techniques prove...

Phase unwrapping (PU) is a key step for the synthetic aperture radar (SAR) interferometry (InSAR). Single-baseline (SB) PU and multi-baseline (MB) are two independently developed technologies, each of which has its own advantages disadvantages. A two-stage programming-based MB method (TSPA) proposed by Yu [1] establishes connection between SB methods. TSPA breaks limitation phase continuity assumption using Chinese remainder theorem (CRT), uses minimum-cost flow (MCF) optimization model to...

The rapidly increasing demand on high-resolution ISAR images causes imaging to become more sensitive errors. This leads the invalidation of plane wave assumption and geometric distortion defocus traditional algorithms. To address this problem, a new algorithm for near-field is proposed which focuses image in two-dimensional (2-D) time-domain without distortion. that end, sub-aperture-based method first applied restore invariance azimuth (IIA). By fixing rotational angle sub-aperture constant...