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A THz Video SAR Imaging Algorithm Based on Chirp Scaling [article]

Jiawei Jiang, Yinwei Li, Qibin Zheng
2022 arXiv   pre-print
In this paper, a terahertz (THz) video SAR imaging algorithm based on chirp scaling is proposed, which utilizes the small synthetic angular feature of THz SAR and the inherent property of linear frequency  ...  In video synthetic aperture radar (SAR) imaging mode, the polar format algorithm (PFA) is more computational effective than the backprojection algorithm (BPA).  ...  In this paper, a THz video SAR imaging algorithm based on chirp scaling is proposed.  ... 
arXiv:2209.08701v1 fatcat:dt7p3e63infqnjnuwrwoh2tf3u

Compressed Sensing for THz FMCW Radar 3D Imaging

Shanshan Gu, Guangrong Xi, Lingyu Ge, Zhong Yang, Yizhi Wang, Weina Chen, Zhenzhong Yu
2021 Complexity  
Aiming at the problems of long data acquisition periods and large sample sizes for the developed imaging system, an algorithm based on compressed sensing is proposed for THz FMCW radar 3D imaging in this  ...  A terahertz (THz) frequency-modulated continuous wave (FMCW) imaging radar system is developed for high-resolution 3D imaging recently.  ...  To reduce imaging data acquirement time and to improve imaging efficiency, an algorithm based on compressed sensing is proposed for 3D imaging of THz FMCW SAR in this paper. e proposed algorithm relies  ... 
doi:10.1155/2021/5576782 doaj:bffcfea34f0d406d82acea7540371985 fatcat:myoynqjlcfcrxjdqe4u4x4ef7y

A Novel Generation Method of High Quality Video Image for High Resolution Airborne ViSAR

Jingwei Chen, Daoxiang An, Wu Wang, Leping Chen, Dong Feng, Zhimin Zhou
2021 Remote Sensing  
For SAR imaging algorithm, polar format algorithm (PFA) is applied, which not only has high efficiency but is also easier to integrate with autofocus algorithms.  ...  Due to sensitivity to motion error, it is very difficult to obtain satisfactory focus quality, especially for SAR systems with a high carrier frequency.  ...  Acknowledgments: The authors would like to thank the Beijing Institute of Radio Measurement for providing the airborne THz-Band Radar data.  ... 
doi:10.3390/rs13183706 fatcat:5nel5zdnc5di5arvax5tpcbrna

Phase Shift Migration with Modified Coherent Factor Algorithm for MIMO-SAR 3D Imaging in THz Band

Guan Yang, Chao Li, Shiyou Wu, Shen Zheng, Xiaojun Liu, Guangyou Fang
2021 Remote Sensing  
In this paper, a phase shift migration (PSM) imaging algorithm based on the explosion reflection model with modified coherent factor was proposed for sidelobe suppression in MIMO-SAR three-dimensional  ...  Finally, a bistatic prototype imaging system in the 0.3 THz band was designed for the proof-of-principle experiments.  ...  Acknowledgments: The authors would like to thank the editors and reviewers for their efforts to help the publication of this work. Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/rs13224701 fatcat:rm6d2rs6b5hvvahblwfrd6t7zq

Phase Shift Migration with SIMO Superposition for MIMO-Sidelooking Imaging at Terahertz Band

Guan Yang, Chao Li, Hang Gao, Guangyou Fang
2020 IEEE Access  
A comprehensive MIMO-SL-EPSM algorithm was established in the wavenumber domain. Proof-of-principle experiments in the 0.1-THz band were performed based on a MIMO-SL prototype system.  ...  The reconstructed images for different targets with high efficiency and quality demonstrate the theoretical results and the effectiveness of the proposed algorithm.  ...  MIMO-PSM algorithm based on the explosion reflection model was proposed for 2-D imaging and achieved imaging quality comparable to BP algorithm with imaging efficiency far faster than BP algorithm.  ... 
doi:10.1109/access.2020.3017617 fatcat:jx6lwwrpmbgc7bhcro62z5mqji

Seeing Around Obstacles with Terahertz Waves [article]

Yiran Cui, Georgios C. Trichopoulos
2022 arXiv   pre-print
THz NLoS imaging can operate in low visibility conditions (e.g., night, strong ambient light, smoke) and uses computationally inexpensive image reconstruction algorithms.  ...  The results show the capability of THz radar imaging systems to recover both the geometry and pose of LoS and NLoS objects with centimeter-scale resolution in various multipath propagation scenarios.  ...  Therefore, an imaging setup based on optics (e.g., lens and mirror) can be bulky with meter-scale optical components [18] .  ... 
arXiv:2205.05066v1 fatcat:o2pp6nwzenbq3krhcfnrsdghki

HIGH-RESOLUTION GRID-INDEPENDENT IMAGING FOR TERAHERTZ 2-D SYNTHETIC APERTURE RADAR WITH SPATIAL UNDER-SAMPLING

Li Ding, Xi Ding, Yangyang Ye, Sixuan Wu, Yiming Zhu
2017 Electromagnetic Waves  
For the purpose of two-dimensional (2-D) imaging in the Terahertz (THz) near field through 2-D synthetic aperture radar technology, Fourier transform (FT) is one of the most popular imaging ways.  ...  However, FT-based algorithms would encounter performance loss either when spatial sampling is under Nyquist frequency or there are off-grid scatterers in the scene of interest.  ...  Operating at difference THz band, [5] has elaborated the outcomes obtained by a 2-D planar SAR with broadband sweep signals, while [6] has proposed an imaging scheme based on frequency-controlled beam  ... 
doi:10.2528/pier17040101 fatcat:vwku6lrvzjh7lnajvcltx5ujze

Three-dimensional terahertz continuous wave imaging radar for nondestructive testing

Xiaoxuan Zhang, Tianying Chang, Zhongmin Wang, Hong-Liang Cui
2020 IEEE Access  
In this paper, an in-house developed broadband linear frequency modulated continuous wave (LFMCW) three-dimensional (3D) THz imaging system is described, and two sets of experimental platforms are set  ...  The third is a 3D reconstruction algorithm based on half space Green's function and the exploding source model for the interior detection of materials with higher refractive index.  ...  Frequency domain SAR algorithm is the first choice for image reconstruction, which can realize pulse compression quickly and effectively by FFT based on the assumptions of range curve offset, platform  ... 
doi:10.1109/access.2020.3014170 fatcat:i2gprnwydncv3bs3l7xe7pot2m

2019 Index IEEE Solid-State Circuits Letters Vol. 2

2019 IEEE Solid-State Circuits Letters  
CMOS Imager and a 3.25- 3.50 THz Quantum Cascade Laser Frequency Comb.  ...  -step Two-Step SAR ADC in 28-nm FDSOI GS/s 8-Bit 12.01-fJ/conv.-step Two-Step SAR ADC in 28-nm FDSOI Technology.  ...  Frequency response  ... 
doi:10.1109/lssc.2020.2967202 fatcat:ka56gc64uvfvbjddesloe5qmnu

Review of Terahertz Tomography Techniques

J. P. Guillet, B. Recur, L. Frederique, B. Bousquet, L. Canioni, I Manek-Hönninger, P. Desbarats, P. Mounaix
2014 Journal of Infrared, Millimeter and Terahertz Waves  
For each technique, we present advantages, drawbacks and limitations for imaging the internal structure of an object.  ...  A tomographic imaging procedure can be used to acquire and to render three-dimensional images in the terahertz frequency range, as in the optical, infrared or X-ray regions of the electromagnetic spectrum  ...  We would also acknowledge financial support from the European community thanks to the contract DOTNAC (Development and Optimization of THz NDT of Aeronautics Composite multilayered structures) -Contract  ... 
doi:10.1007/s10762-014-0057-0 fatcat:3sqnw4wgpre7jgngmwlletthj4

A NEAR-FIELD 3D CIRCULAR SAR IMAGING TECHNIQUE BASED ON SPHERICAL WAVE DECOMPOSITION

Biao Zhang, Yiming Pi, Rui Min
2013 Electromagnetic Waves  
A near-field three dimensional imaging algorithm for circular SAR is proposed in this paper.  ...  By comparing the results with the focusing operator algorithm and the back-projection algorithm, it is found that the proposed algorithm is more efficient and can obtain a good imaging performance.  ...  In this paper, we propose a 3D near-field imaging algorithm for CSAR which is based on spherical wave decomposition theory.  ... 
doi:10.2528/pier13052011 fatcat:s32oh3uxobcdre5brgjdavvh34

Table of contents

2019 2019 Photonics & Electromagnetics Research Symposium - Fall (PIERS - Fall)  
on Compressed Sensing . . . . . . . . . . . . . . . 1295 A Novel Radio Frequency Interference Suppression Method for SAR Based on Spectrum Extrapolation1300 An Accurate Modeling Method for Near-field  ...  on Frequency-sparse 3-D Imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1233 Imaging Detection for the Discharge of Polluted Insulators Based on Iterative  ... 
doi:10.1109/piers-fall48861.2019.9021769 fatcat:tkvlcifbifgolbr3u3kt5j3jra

Ultra Wide X-Band Microwave Imaging of Concealed Weapons and Explosives Using 3D-SAR Technique

P. Millot, L. Casadebaig
2015 International Journal of Antennas and Propagation  
In order to detect and image concealed weapons and explosives, an electromagnetic imaging tool with its related signal processing is presented.  ...  The apparatus and the 3D near-field SAR processor are described. A strategy for contour identification is presented with results of some simulants of weapon and explosive.  ...  Acknowledgment The authors are very grateful to the European Defense Agency for having partially funded the ONERA Lab for explosive detection studies in the framework of the E-STAR project.  ... 
doi:10.1155/2015/528103 fatcat:xj3tfnvluzbgbpdioggr2pfwsm

1.56 Terahertz 2-frames per second standoff imaging

Thomas M. Goyette, Jason C. Dickinson, Kurt J. Linden, William R. Neal, Cecil S. Joseph, William J. Gorveatt, Jerry Waldman, Robert Giles, William E. Nixon, Kurt J. Linden, Laurence P. Sadwick
2008 Terahertz Technology and Applications  
The system design was based on a 2.5 m standoff distance, with a capability of visualizing a 0.5 m by 0.5 m scene at an image rate of 2 frames per second.  ...  The system optical design consisted of a 1.56 THz laser beam, which was raster swept by a dual torsion mirror scanner.  ...  The system design was based on a 2.5 m standoff distance, with a capability of visualizing a 0.5 m by 0.5 m scene at an image rate of 2 frames/second.  ... 
doi:10.1117/12.764672 fatcat:6wn7kirpovexrnuaaz7sqoro2q

Space-based Sub-THz ISAR for Space Situational Awareness Concept and Design

Emidio Marchetti, Andrew G. Stove, Edward G. Hoare, Mikhail Cherniakov, David Blacknell, Marina Gashinova
2021 IEEE Transactions on Aerospace and Electronic Systems  
Operation at sub-THz frequencies in the band 200 GHz -400 GHz benefits from wide available bandwidth, high sensitivity to surface texture and very small target features, and requires an antenna of small  ...  The concept of sub-terahertz (sub-THz) imaging and recognition of space objects by a satellite based inverse synthetic aperture radar (ISAR) is proposed and analyzed in this paper.  ...  ISAR IMAGE FORMATION METHODS There is an extensive literature on ISAR image formation, see for example [6] and the reason for re-visiting the algorithms here is to propose those which are most appropriate  ... 
doi:10.1109/taes.2021.3126375 fatcat:kakj6ybgebcwniful5dxphhnxy
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