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A VARIABLE PRF IMAGING METHOD FOR HIGH SQUINT DIVING SAR

Huaping Xu, Jing Gao, Jianlong Li
2013 Electromagnetic Waves  
Comparison to the traditional constant PRF, the novel variable PRF method for high squint needs less storage and less time expense, which is helpful to real time SAR imaging.  ...  This paper proposes the varied azimuth sample frequency (Pulse Repeat Frequency, PRF) to implement the high squint diving SAR imaging.  ...  ACKNOWLEDGMENT The authors would like to thank the anonymous reviewers for their valuable comments and useful suggestions.  ... 
doi:10.2528/pier12112304 fatcat:h2yxp7yx6vf7rirbrjfdmwdnky

Chirp scaling algorithm for processing SAR data with high-squint angle and motion error

Alberto Moreira, Yonghong Huang, Giorgio Franceschetti
1994 SAR Data Processing for Remote Sensing  
This paper proposes a modified chirp scaling algorithm which is suitable for the processing of highly squinted data with motion errors.  ...  The new approach, denoted as extended chirp scaling (ECS), is considered to be a generalized algonthm suitable for the high resolution processing of most airborne SAR systems.  ...  For high squint angles and low frequencies, this error will affect the image quality.  ... 
doi:10.1117/12.197547 fatcat:pvhv4o2mdnatzgqe43dpxhavyi

Modified Omega-k Algorithm for High-Speed Platform Highly-Squint Staggered SAR Based on Azimuth Non-Uniform Interpolation

Hong-Cheng Zeng, Jie Chen, Wei Liu, Wei Yang
2015 Sensors  
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.  ...  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  ...  Processing Algorithm for High-Speed Platform Highly-Squint Staggered SAR In this section, the traditional algorithm for high-speed platform highly-squint staggered SAR is introduced first, and then, based  ... 
doi:10.3390/s150203750 pmid:25664433 pmcid:PMC4367383 fatcat:fmbt4yghwzfxjleeq3s6patngm

A Novel Imaging Algorithm for Focusing High-Resolution Spaceborne SAR Data in Squinted Sliding-Spotlight Mode

Jie Chen, Hui Kuang, Wei Yang, Wei Liu, Pengbo Wang
2016 IEEE Geoscience and Remote Sensing Letters  
Finally, a novel imaging algorithm is proposed, with its effectiveness demonstrated by simulation results.  ...  To process squinted sliding-spotlight synthetic aperture radar (SAR) data, the azimuth preprocessing step based on the linear range walk correction (LRWC) and de-rotation operations is implemented to eliminate  ...  Moreover, since the backscattering properties of some targets are likely to vary as a function of squint angle, the squinted SAR can obtain more information for ROI with multiple images at different squint  ... 
doi:10.1109/lgrs.2016.2598066 fatcat:47bjwn3zvfcsjfnrvg6a4pepdm

High-Temporal-Resolution High-Spatial-Resolution Spaceborne SAR Based on Continuously Varying PRF

Zhirong Men, Pengbo Wang, Chunsheng Li, Jie Chen, Wei Liu, Yue Fang
2017 Sensors  
An efficient data acquisition technique for high-temporal-resolution, high-spatial-resolution and high-squint-angle spaceborne SAR, in which the pulse repetition frequency (PRF) is continuously varied  ...  This paper considers a novel high-squint-angle system intended to acquire high-spatial-resolution spaceborne SAR images with repeat-observation intervals varying from tens of seconds to several minutes  ...  In Section 5, the relevant imaging algorithm for high-resolution high-squint spaceborne SAR, based on CVPRF, is developed.  ... 
doi:10.3390/s17081700 pmid:28757547 pmcid:PMC5579889 fatcat:mm2hrg2pura67owjybgqcrjwpa

Fast image-formation algorithm for ultrahigh-resolution airborne squint spotlight synthetic aperture radar based on adaptive sliding receive-window technique

Yang Wei, Zeng Hong-cheng, Chen Jie, Wang Peng-bo
2014 Journal of Applied Remote Sensing  
., the processing efficiency could be improved by 17 times in the 70deg squint angle by applying the proposed image algorithm to the squint spotlight ASRW-SAR data.  ...  Airborne squint spotlight SAR varies its receive-window starting time pulse-by-pulse as a function of range-walk, namely, the linear term of range cell migration (RCM).  ...  Acknowledgments The authors would like to thank the anonymous reviewers for their valuable comments and useful suggestions.  ... 
doi:10.1117/1.jrs.8.083620 fatcat:7sarffn6qffidk5eqn7yhrpnhy

A Novel Sidelobe Reduction Algorithm Based on Two-Dimensional Sidelobe Correction Using D-SVA for Squint SAR Images

Min Liu, Zhou Li, Lu Liu
2018 Sensors  
Various methods have been proposed for broadside SAR, which can suppress the sidelobes effectively while maintaining high image resolution at the same time.  ...  Then, the sidelobe suppression is achieved by applying the D-SVA algorithm to the pre-processed data. Finally, an inverse transform is performed as a post-processing for the squint SAR images.  ...  Author Contributions: Min Liu proposed the algorithm, performed the experiments and wrote the paper; Zhou Li provided important suggestions to improve the algorithm; Lu Liu provided consultation and advices  ... 
doi:10.3390/s18030783 pmid:29510584 pmcid:PMC5876743 fatcat:gmu4bya7lbbdhiihtsfybabzsa

Extended wavenumber-domain synthetic aperture radar focusing with integrated motion compensation

A. Reigber, E. Alivizatos, A. Potsis, A. Moreira
2006 IEE Proceedings - Radar Sonar and Navigation  
High-quality SAR processing methods, which are able to deal with such sensor parameters, are necessary for focusing the raw data of such sensors.  ...  very robust in the cases of long synthetic apertures and high squint angles.  ...  However, for more general system parameters, an additional third-order MoCo step is necessary to achieve high image quality.  ... 
doi:10.1049/ip-rsn:20045087 fatcat:zkvt7daefjhp3hfv3bjlio4sje

Generalized Nonlinear Chirp Scaling Algorithm for High-Resolution Highly Squint SAR Imaging

Tianzhu Yi, Zhihua He, Feng He, Zhen Dong, Manqing Wu
2017 Sensors  
A number of imaging algorithms have been presented for the squint SAR data.  ...  Simulation results show that the GNLCS algorithm can enlarge the ADOF and focusing precision for high-resolution highly squint SAR data. 2 of 15 squint SAR [1].  ...  algorithm for high-resolution highly squint SAR are as follows: Step 1.  ... 
doi:10.3390/s17112568 pmid:29112151 pmcid:PMC5712855 fatcat:qyk43m5rszfohfdmbu3odswkea

MOTION COMPENSATION FOR SQUINT MODE SPOTLIGHT SAR IMAGING USING EFFICIENT 2D INTERPOLATION

Sang-Hong Park, Jong-Il Park, Kyung-Tae Kim
2012 Electromagnetic Waves  
Because conventional 2D interpolation requires huge computation time and yields large computation errors, we propose an efficient 2D interpolation technique for squint-mode RMA composed of two 1D interpolations  ...  In the squint mode airborne spotlight synthetic aperture radar system using the range migration algorithm (RMA), autofocus (AF) technique yields poor results due to the squint spreading of the point spread  ...  RMA to derive SAR image using (1) is composed of four steps [4, 14] ; 2D Fourier transform (FT) of s (t, u), 2D matched filtering, 1D interpolation in the frequency of down-range, and final 2D inverse  ... 
doi:10.2528/pier12040201 fatcat:d4r7hmvoerc4zpbo5zxefwyvmy

Range migration algorithm for airborne squint mode spotlight SAR imaging

H.-S. Shin, J.-T. Lim
2007 IET radar, sonar & navigation  
Thus, the modified reference signal to transform a squint-mode data to a broadside-mode data is introduced on the basis of the coordinate transformation and the extended Taylor approximation.  ...  (SAR) data.  ...  Step 3: As shown in Fig. 4 , to rotate the flight path and transform the coordinate for each subarea, we use the squint angles given in step 2.  ... 
doi:10.1049/iet-rsn:20060080 fatcat:uzue34bmmvg3da6egqvvzqw3sm

Interferometric SAR signal analysis in the presence of squint

M. Bara, R. Scheiber, A. Broquetas, A. Moreira
2000 IEEE Transactions on Geoscience and Remote Sensing  
This paper develops an analysis of the SAR impulse response function from the interferometric point of view, with the intention of studying its phase behavior in the presence of high squint angle values  ...  This behavior, if not compensated, imposes strong limits on the performance of the interferometric techniques in a squinted case, especially for airborne SAR systems.  ...  ACKNOWLEDGMENT The authors would like to thank the anonymous reviewers for their comments and suggestions.  ... 
doi:10.1109/36.868875 fatcat:vhekkrr5uvbpbe62ca4geeyhqm

NEW DEVELOPMENT OF TWO-STEP PROCESSING APPROACH FOR SPOTLIGHT SAR FOCUSING IN PRESENCE OF SQUINT

Yajun Mo, Yun-Kai Deng, Yun-Hua Luo, Bing-Ji Zhao, He Yan
2013 Electromagnetic Waves  
Based on the analysis, a novel approach for squinted spotlight SAR is proposed in this paper.  ...  This approach extends the focusing capacity of traditional two-step processing approach from broadside spotlight SAR to squinted case.  ...  The authors would like to thank the anonymous reviewers for their valuable comments and constructive suggestions that help improve the manuscript significantly.  ... 
doi:10.2528/pier13022801 fatcat:m2faygc7fbav5hhv4bj7te3sem

Precise Aperture-Dependent Motion Compensation with Frequency Domain Fast Back-Projection Algorithm

Man Zhang, Guanyong Wang, Lei Zhang
2017 Sensors  
Because of its high accuracy, PTA is one of the most widely used algorithms for azimuth-variant MOCO in real airborne SAR imagery.  ...  However, the two-step MOCO method neglects the residual azimuth-variant motion errors, thus the focusing performance decreases for SAR imagery with wide beam and high resolution, especially when the atmospheric  ...  Compared with PTA, FDFBPA promises fully focused images with high efficiency and robustness, and is suitable for real airborne SAR imagery.  ... 
doi:10.3390/s17112454 pmid:29072608 pmcid:PMC5712856 fatcat:u36dyysy75fmzieeen5f2c742i

Robust GMTI Scheme for Highly Squinted Hypersonic Vehicle-Borne Multichannel SAR in Dive Mode

Jiusheng Han, Yunhe Cao, Wenhua Wu, Yang Wang, Tat-Soon Yeo, Shuai Liu, Fengfei Wang
2021 Remote Sensing  
GMTI scheme for the highly squinted HSV-MC-SAR in dive mode, is novel.  ...  Then, based on the proposed model, a robust GMTI scheme is derived in detail, paying particular attention to Doppler ambiguity arising from the high-speed and high-resolution wide-swath.  ...  The proposed GMTI scheme for HSV-MC-SAR is new and focuses the region of interested on the high-squint side of a dive orbit.  ... 
doi:10.3390/rs13214431 fatcat:m6xkbn6xqvfsvfa2ekmgrruokm
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