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1. Hollow spherical NiFe-MOF derivative and N-doped rGO composites towards the tunable wideband electromagnetic wave absorption: Experimental and theoretical study

Author:
Huiting Zhao; Qijie Wang; Haolun Ma; Yu Zhao; Ling Li; Pinbo Li; Junfeng Yan; Jiangni Yun; Wu Zhao; Han Zhang; Zhiyong Zhang; Chang Liu
Source:
Carbon 2023 v.201 pp. 347-361
ISSN:
0008-6223
Subject:
radar,   etc   ; absorption; electromagnetic field; electromagnetic radiation; energy; graphene; nanosheets;     Show all 7 Subjects
Abstract:
... N-doped rGO (N-rGO) based nano materials are considered to be competent candidates for absorbing electromagnetic waves (EMWs), owing to the low filler loading and abundant relaxation polarization losses. With a unique multistage porous structure, NiFe@N–C/rGO, derived from the composite of NiFe-MOF anchoring on GO nanosheeets, was successfully constructed by a facile solvothermal method and high-t ...
DOI:
10.1016/j.carbon.2022.09.039

2. Three-dimensional porous manganese oxide/nickel/carbon microspheres as high-performance electromagnetic wave absorbers with superb photothermal property

Author:
Xiangwei Meng; Jing Qiao; Yunfei Yang; Xue Zhang; Zhengyi Yang; Sinan Zheng; Jiurong Liu; Lili Wu; Zhou Wang; Fenglong Wang
Source:
Journal of colloid and interface science 2023 v.629 pp. 884-894
ISSN:
0021-9797
Subject:
radar,   etc   ; absorption; carbon; carbonization; durability; electromagnetic radiation; magnetism; manganese monoxide; microparticles; nanoparticles; nickel;     Show all 11 Subjects
Abstract:
... Regulating electromagnetic parameters and thus improving impedance matching characteristics by multi-component design is regarded as a prospective approach to obtain highly efficient electromagnetic wave absorption materials. Whereas, it is still challenging to fabricate microwave absorbers with strong absorption capacity and durability in harsh conditions. Based on the above considerations, three ...
DOI:
10.1016/j.jcis.2022.09.043

3. E-Region Field-Aligned Irregularities in the Middle of a Solar Eclipse Observed by a Bistatic Radar

Author:
Lei Qiao; Gang Chen; Wanlin Gong; Xuesi Cai; Erxiao Liu; Mingkun Su; Xuyang Teng; Zhaoyang Qiu; Huina Song
Source:
Remote Sensing 2022 v.14 no.2 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; gravity; ionization;     Show all 3 Subjects
Abstract:
... The Wuhan Ionospheric Oblique Backscatter Sounding System (WIOBSS) was applied as a bistatic radar to record the ionospheric E-region responses to a solar eclipse on 22 July 2009. The transmitter was located in Wuhan and the receiver was located in Huaian. The receiver observed anomalous echoes with larger Doppler shifts at the farther ranges compared with the echoes reflected by Es. According to ...
DOI:
10.3390/rs14020392

4. MV-GPRNet: Multi-View Subsurface Defect Detection Network for Airport Runway Inspection Based on GPR

Author:
Nansha Li; Renbiao Wu; Haifeng Li; Huaichao Wang; Zhongcheng Gui; Dezhen Song
Source:
Remote Sensing 2022 v.14 no.18 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; airports; algorithms;     Show all 3 Subjects
Abstract:
... The detection and restoration of subsurface defects are essential for ensuring the structural reliability of airport runways. Subsurface inspections can be performed with the aid of a robot equipped with a Ground Penetrating Radar (GPR). However, interpreting GPR data is extremely difficult, as GPR data usually contains severe clutter interference. In addition, many different types of subsurface d ...
DOI:
10.3390/rs14184472

5. MIMO Radar Sparse Recovery Imaging with Wideband Interference Prediction

Author:
Tao Pu; Ningning Tong; Weike Feng; Pengcheng Wan; Xiaowei Hu
Source:
Remote Sensing 2022 v.14 no.15 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; algorithms; prediction;     Show all 3 Subjects
Abstract:
... Multiple-input multiple-output (MIMO) radar three-dimensional (3D) imaging is widely applied in military and civil fields. However, MIMO is easily affected by wideband interference (WBI). To solve this problem, in this study, we propose a sparse recovery imaging method with WBI prediction based on the predictive recurrent neural network (PredRNN) and the tensor-based smooth L0 (TSL0) algorithm. Fi ...
DOI:
10.3390/rs14153774

6. Reinforcement Learning for Compressed-Sensing Based Frequency Agile Radar in the Presence of Active Interference

Author:
Shanshan Wang; Zheng Liu; Rong Xie; Lei Ran
Source:
Remote Sensing 2022 v.14 no.4 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; cognition; environmental knowledge;     Show all 3 Subjects
Abstract:
... Compressed sensing (CS)-based frequency agile radar (FAR) is attractive due to its superior data rate and target measurement performance. However, traditional frequency strategies for CS-based FAR are not cognitive enough to adapt well to the increasingly severe active interference environment. In this paper, we propose a cognitive frequency design method for CS-based FAR using reinforcement learn ...
DOI:
10.3390/rs14040968

7. A framework for comparing two rainfields based on spatial structure: A case of radar against selected satellite precipitation products over southeast Queensland, Australia

Author:
Yeboah Gyasi-Agyei
Source:
Journal of hydrology 2022 v.613 pp. 128356
ISSN:
0022-1694
Subject:
radar,   etc   ; hydrology; satellites; Queensland;     Show all 4 Subjects
Abstract:
... Rain gauge networks are not adequate to capture the complex spatial structure of rainfall for meaningful urban flood studies. While radar and satellite precipitation products (SPPs) are being developed to alleviate the limitations of rain gauge networks, they need to be evaluated for regional applications. This study compared radar against 3 SPPs of IMERG (Integrated Multi-satellite Retrievals for ...
DOI:
10.1016/j.jhydrol.2022.128356

8. The Dynamic Sea Clutter Simulation of Shore-Based Radar Based on Stokes Waves

Author:
Feng Luo; Yao Feng; Guisheng Liao; Linrang Zhang
Source:
Remote Sensing 2022 v.14 no.16 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; models; wind speed;     Show all 3 Subjects
Abstract:
... The sea clutter model based on the physical sea surface can simulate radar echo at different times and positions and is more suitable for describing dynamic sea clutter than the traditional models based on statistical significance. However, when applying the physical surface model to shore-based radar, the effects of wave nonlinearity, breaking wave, shadow, and radar footprint size must be consid ...
DOI:
10.3390/rs14163915

9. Integrating topographic knowledge into deep learning for the void-filling of digital elevation models

Author:
Sijin Li; Guanghui Hu; Xinghua Cheng; Liyang Xiong; Guoan Tang; Josef Strobl
Source:
Remote sensing of environment 2022 v.269 pp. 112818
ISSN:
0034-4257
Subject:
radar,   etc   ; environment; landscapes; topography;     Show all 4 Subjects
Abstract:
... Digital elevation models (DEMs) contain some of the most important data for providing terrain information and supporting environmental analyses. However, the applications of DEMs are significantly limited by data voids, which are commonly found in regions with rugged terrain. We propose a novel deep learning-based strategy called a topographic knowledge-constrained conditional generative adversari ...
DOI:
10.1016/j.rse.2021.112818

10. Wavelet analysis and NDT for condition assessment of historic Masonry Bridge

Author:
Gokhan Kilic
Source:
Structures 2022 v.45 pp. 275-283
ISSN:
2352-0124
Subject:
radar,   etc   ; infrastructure; thermography; wavelet;     Show all 4 Subjects
Abstract:
... Maintaining a country’s heritage requires the implementation of methods that enable the condition assessment of historic infrastructure, preferably with zero damage/interventions and minimum post-inspections. Non-Destructive Techniques (NDT) can meet such criteria in a timely and cost-efficient manner. These techniques include High Definition and Infrared Thermography (IRT) drone systems to assess ...
DOI:
10.1016/j.istruc.2022.09.008

11. Characteristics of Regions with High-Density Initiation of Flashes in Mesoscale Convective Systems

Author:
Fei Wang; Yijun Zhang; Xiaohua Deng; Hengyi Liu; Wansheng Dong; Wen Yao
Source:
Remote Sensing 2022 v.14 no.5 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; altitude; evolution; lightning;     Show all 4 Subjects
Abstract:
... To investigate the characteristics of regions exhibiting multiple lightning initiations within a finite volume and a short time, the lightning location data obtained from the convective regions of 14 mesoscale convective systems were analyzed in combination with data from radar. In total, 415 out of 5996 radar grids (1 km × 1 km × 0.5 km) were found to initiate more than one flash within 6 min. On ...
DOI:
10.3390/rs14051193

12. High-Frequency Channel Modeling Based on the Multi-Source Ionospheric Assimilation Model

Author:
Mingjie Lv; Chen Zhou; Tongxin Liu; Jiandong Qiao; Wei Qiao; Chen Li; Junming Wang; Jianhua Zhu
Source:
Remote Sensing 2022 v.14 no.17 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; prediction; simulation models;     Show all 3 Subjects
Abstract:
... In this paper, we explored how to more accurately predict the quality of high-frequency links and how to better research and improve the capabilities of high-frequency communication, reconnaissance, and positioning systems. Based on the background electron density generated by the ionospheric assimilation model and 3D ray-tracing technology, more realistic and accurate high-frequency channel param ...
DOI:
10.3390/rs14174133

13. Land Subsidence Monitoring Method in Regions of Variable Radar Reflection Characteristics by Integrating PS-InSAR and SBAS-InSAR Techniques

Author:
Peng Zhang; Zihao Guo; Shuangfeng Guo; Jin Xia
Source:
Remote Sensing 2022 v.14 no.14 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; interferometry; subsidence; vegetation;     Show all 4 Subjects
Abstract:
... In the InSAR solution, the uneven distribution of permanent scatterer candidates (PSCs) or slowly decoherent filtering phase (SDFP) pixel density in a region of variable radar reflection feature can cause local low accuracy in single interferometry. PSCs with higher-order coherence in Permanent Scatter InSAR (PS-InSAR) are generally distributed in those point targets of urban built-up areas, and S ...
DOI:
10.3390/rs14143265

14. Target Height Measurement under Complex Multipath Interferences without Exact Knowledge on the Propagation Environment

Author:
Yuan Liu; Hongwei Liu
Source:
Remote Sensing 2022 v.14 no.13 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; algorithms; landscapes; models;     Show all 4 Subjects
Abstract:
... This paper investigates the direction-of-arrival (DOA) estimation-based target localization problem using an array radar under complex multipath propagation scenarios. Prevalent methods may suffer from performance degradation due to the deterministic signal model mismatch, especially when the exact knowledge of a propagation environment is unavailable. To cope with this problem, we first establish ...
DOI:
10.3390/rs14133099

15. Adaptive Square-Root Unscented Kalman Filter Phase Unwrapping with Modified Phase Gradient Estimation

Author:
Yansuo Zhang; Shubi Zhang; Yandong Gao; Shijin Li; Yikun Jia; Minggeng Li
Source:
Remote Sensing 2022 v.14 no.5 pp. -
ISSN:
2072-4292
Subject:
synthetic aperture radar,   etc   ; algorithms; interferometry;     Show all 3 Subjects
Abstract:
... Phase unwrapping (PU) is a key program in data processing in the interferometric synthetic aperture radar (InSAR) technique, and its accuracy directly affects the quality of final SAR data products. However, PU in regions with large gradient changes and high noise has always been a difficult problem. To overcome the limitation, this article proposes an adaptive square-root unscented Kalman filter ...
DOI:
10.3390/rs14051229

16. Assessment of Polar Ionospheric Observations by VIPIR/Dynasonde at Jang Bogo Station, Antarctica: Part 1—Ionospheric Densities

Author:
Eunsol Kim; Geonhwa Jee; Young-Bae Ham; Nikolay Zabotin; Changsup Lee; Hyuck-Jin Kwon; Junseok Hong; Jeong-Han Kim; Terence Bullett
Source:
Remote Sensing 2022 v.14 no.12 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; computer software; summer; Antarctica;     Show all 4 Subjects
Abstract:
... Vertical incidence pulsed ionospheric radar (VIPIR) has been operated to observe the polar ionosphere with Dynasonde analysis software at Jang Bogo Station (JBS), Antarctica, since 2017. The JBS-VIPIR-Dynasonde (JVD) provides ionospheric parameters such as the height profile of electron density with NmF2 and hmF2, the ion drift, and the ionospheric tilt in the bottomside ionosphere. The JBS (74.6° ...
DOI:
10.3390/rs14122785

17. Micro-Doppler Feature Extraction of Rotating Structures of Aircraft Targets with Terahertz Radar

Author:
Xiaoyu Qin; Bin Deng; Hongqiang Wang
Source:
Remote Sensing 2022 v.14 no.16 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; aircraft; algorithms; models; wavelet;     Show all 5 Subjects
Abstract:
... The micro-Doppler features formed by the micro-motion of rotating blades of rotors and turbines are of great significance for aircraft target detection and recognition. Mastering the micro-motion features is the premise of radar target identification. The blades’ length and rotation rate are vital parameters for classifying aircraft targets. One can instantly judge the type and state of the target ...
DOI:
10.3390/rs14163856

18. On the potential of commercial microwave link networks for high spatial resolution rainfall monitoring in urban areas

Author:
Xin Zheng; Hagit Messer; Qian Wang; Tao Xu; Youwei Qin; Tao Yang
Source:
Atmospheric research 2022 v.277 pp. 106289
ISSN:
0169-8095
Subject:
radar,   etc   ; rain; research; urban areas;     Show all 4 Subjects
Abstract:
... The considerable density of commercial microwave links (CMLs) in urban areas provides an unprecedented opportunity to reconstruct rain fields with high spatial resolution. The aim of this study was to investigate the potential advantages of CML measurements for rain field reconstruction. To this end, we compared the performance of equivalent sensor networks consisting of CMLs, rain gauges (RGs), o ...
DOI:
10.1016/j.atmosres.2022.106289

19. Stratiform and Convective Rain Classification Using Machine Learning Models and Micro Rain Radar

Author:
Wael Ghada; Enric Casellas; Julia Herbinger; Albert Garcia-Benadí; Ludwig Bothmann; Nicole Estrella; Joan Bech; Annette Menzel
Source:
Remote Sensing 2022 v.14 no.18 pp. -
ISSN:
2072-4292
Subject:
radar,   etc   ; microstructure; probability; rain; Spain;     Show all 5 Subjects
Abstract:
... Rain type classification into convective and stratiform is an essential step required to improve quantitative precipitation estimations by remote sensing instruments. Previous studies with Micro Rain Radar (MRR) measurements and subjective rules have been performed to classify rain events. However, automating this process by using machine learning (ML) models provides the advantages of fast and re ...
DOI:
10.3390/rs14184563

20. Accurate contactless sleep apnea detection framework with signal processing and machine learning methods

Author:
Zhongxu Zhuang; Fengxia Wang; Xuan Yang; Li Zhang; Chang-Hong Fu; Jing Xu; Changzhi Li; Hong Hong
Source:
Methods 2022 v.205 pp. 167-178
ISSN:
1046-2023
Subject:
radar,   etc   ; biometry; sleep; sleep apnea;     Show all 4 Subjects
Abstract:
... The detection of sleep apnea is critical for assessing sleep quality. It is also a proven biometric in diagnosing cardiovascular and other diseases. Recent studies have shown that radar-based non-contact vital sign monitoring system can effectively detect sleep apnea. However, the detection accuracy in the current study still needs to be improved. In this paper, we propose a sleep apnea detection ...
DOI:
10.1016/j.ymeth.2022.06.013