- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Novel Algorithm for High Resolution Passive Radar Imaging with ISDB-T DIGITAL TV Signal
摘要： We have studied passive radar with digital broadcasting terrestrial signals for imaging moving and stationary targets. We combined multiple TV channels to improve the range resolution. In order to reduce the high-level sidelobes caused by the frequency gaps among multiple channels, a low rank matrix completion based method is proposed. We present the experiment results of range-Doppler mapping of moving targets, high-resolution time delay estimation, and passive synthetic aperture radar (SAR) imaging of stationary targets. It is shown that, by the designed system, a landing airplane can be detected and tracked. By combining multiple TV channels, high resolution time delay estimation can be achieved. Buildings located within 55 meters can be effectively imaged by the proposed method.
关键词： synthetic aperture radar,low rank matrix completion,ISDB-T,Passive radar
更新于2025-09-04 15:30:14
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SAR Image Change Detection Using Saliency Extraction and Shearlet Transform
摘要： Change detection has recently become a topic of great significance in the field of remote sensing. However, as one of the traditional effective detection methods, synthetic aperture radar (SAR) image change detection based on wavelet transform fusion remains limited because of the existence of speckle noise and because multidirectional information has been underutilized. Therefore, we propose an unsupervised change detection method using saliency extraction and the shearlet transform. Saliency extraction is first used to homogenize registered images to reduce speckle noise. Using a subtraction operation for preprocessed binary images, we then obtain a saliency-guided difference image (DI) that includes the main contour change information. Then, the Gauss-log-ratio DI includes the detailed change information at the edge of the image and acts as an auxiliary DI. Next, two DIs are fused with the shearlet transform. During this process, the DI is decomposed into one low-frequency and four high-frequency subimages. The low-frequency subimage contains image contour information and the high-frequency subimages contain the edge information of the images. Compared to wavelet fusion, in our method, no extra fusion noise occurs because the shearlet transform performs multiscale analysis. The final change map can be obtained through maximum entropy segmentation. Real SAR image pairs in areas of Bern, Switzerland, and Suzhou, China, are used to verify the proposed change detection method. The experimental results demonstrate the effectiveness of the proposed method when compared to the reference methods.
关键词： synthetic aperture radar (SAR),multidirectional information,saliency extraction,Change detection,shearlet transform
更新于2025-09-04 15:30:14
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A New Hurricane Wind Direction Retrieval Method for SAR Images without Hurricane Eye
摘要： This study presents a new approach for hurricane wind direction retrieval utilizing rainband streaks contained in synthetic aperture radar (SAR) images without hurricane eye information, based on the hurricane inflow angle. To calculate the wind direction field, a method for estimating the location of the hurricane center is given. In this paper, four Sentinel-1A (S-1A) images with a hurricane eye are used to clarify the center estimation method. Three S-1A SAR images without a hurricane eye are studied to evaluate the accuracy of the new method. The estimated locations of hurricane centers show good agreement with hurricane track data provided by the National Oceanic and Atmospheric Administration (NOAA)’s Atlantic Oceanographic and Meteorological Laboratory (AOML) Hurricane Research Division (HRD), HurricaneCity, and the National Institute of Informatics (NII). To validate the estimated wind directions, the NOAA HRD dropwindsonde observations for Tropical Storm Karl are collected and compared. The wind directions retrieved by our approach are more consistent with visual inspection than the fast Fourier transform (FFT) method in subimages. Moreover, the retrieved wind speeds utilizing C-band model 5.N (CMOD5.N) are compared with wind speed estimations observed by Stepped Frequency Microwave Radiometer (SFMR). The results suggest that the proposed method has good potential to retrieve hurricane wind direction from SAR images without a hurricane eye and external data.
关键词： synthetic aperture radar (SAR),hurricane inflow angle,Sentinel-1A (S-1A),Stepped Frequency Microwave Radiometer (SFMR),hurricane wind direction retrieval,CMOD5.N,rainband streaks
更新于2025-09-04 15:30:14
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[Lecture Notes in Computer Science] Neural Information Processing Volume 11301 (25th International Conference, ICONIP 2018, Siem Reap, Cambodia, December 13-16, 2018, Proceedings, Part I) || Proposal of Complex-Valued Convolutional Neural Networks for Similar Land-Shape Discovery in Interferometric Synthetic Aperture Radar
摘要： We propose a complex-valued convolutional neural network to extract the areas having land shapes similar to samples in interferometric synthetic aperture radar (InSAR). InSAR extends its application to various earth observations such as volcano monitoring and earthquake damage estimation. Since the amount of data is increasing drastically in these years, it is necessary to structurize them in a big data framework. In this paper, experiments demonstrate that similar small volcanoes are grouped into a single class. We ?nd that the neural network is capable of discovering unidenti?ed lands similar to prepared samples successfully.
关键词： Complex-valued neural network (CVNN),Interferometric synthetic aperture radar (InSAR),Feature discovery
更新于2025-09-04 15:30:14
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Sparse SAR Image Formation of Moving Targets-A Reweighted Sparse Approach
摘要： For multi-channel synthetic aperture radar of ground moving target imaging (SAR GMTIm), the moving targets in SAR image domain are sparse after clutter suppression, which provides the possibility of using sparse approach. In this paper, a reweighted sparse algorithm of SAR GMTIm is proposed to improve the imaging performance. Intuitively, both the magnitude and interferometric phase can exhibit the moving target signatures by applying displaced phase center antenna (DPCA) technique and along-track interferometry (ATI), respectively. So a hybrid metric of magnitude and interferometric phase is constructed to be as the weights of the reweighted sparse approach. Compared with the unweighted approach, the proposed reweighed approach can effectively improve the sparse imaging performance. Finally, experiments using measured data are performed to confirm the effectiveness of the proposed algorithm.
关键词： ground moving target imaging (GMTIm),magnitude and interferometric phase,reweighted sparse approach,Synthetic aperture radar (SAR)
更新于2025-09-04 15:30:14
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SAR Ground Moving Target Imaging Based on a New Range Model Using a Modified Keystone Transform
摘要： Imaging of a ground moving target (GMT) with synthetic aperture radar (SAR) is a challenging task, particularly when the Doppler ambiguity happens. This paper proposes a novel GMT range model and a novel Doppler ambiguity-tolerated GMT imaging algorithm based on modified keystone transform. In the proposed GMT range model, the range from radar antenna to the scattering center on the target is divided into two parts: the range from radar antenna to the target centroid and the projection length on the light of sight from the target centroid to the scattering center. Based on the new range model, a Doppler ambiguity-tolerated range cell migration correction (RCMC) method is proposed, in which keystone transform is modified to realize the differential RCMC by interpolation with nonzero phase sinc kernel. Finally, the GMT image is obtained in the range-Doppler domain by matched filtering in the slow-time domain and is restored into the 2-D space domain. The effectiveness of our proposed model and imaging method is demonstrated by both simulated and real airborne SAR data.
关键词： Ground moving target imaging (GMTIm),keystone transform,range cell migration correction (RCMC),range model,synthetic aperture radar (SAR)
更新于2025-09-04 15:30:14
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[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - SAR Target Classification with CycleGAN Transferred Simulated Samples
摘要： Target classification is an important part in automatic target recognition (ATR) systems. Deep learning methods get state of art performance in SAR target classification. Simulation is a useful data augmentation method when the numbers of real samples for training is not sufficient. This article discusses how to release the full potential of simulated samples which is used to improve performance of SAR target classifier. The proposed method is based on cycle adversarial network (CycleGAN), which can transfer simulated samples to be more similar with real samples in image domain. Experiments show that adding simulated samples straightforward into training dataset is not helpful to improve the performance. However, adding the transferred simulated samples for training results in about 10% increase in accuracy in the designed SAR airplane classification experiment, compared with training without data augmentation.
关键词： Synthetic aperture radar,data augmentation,target classification
更新于2025-09-04 15:30:14
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[IEEE 2018 10th IAPR Workshop on Pattern Recognition in Remote Sensing (PRRS) - Beijing (2018.8.19-2018.8.20)] 2018 10th IAPR Workshop on Pattern Recognition in Remote Sensing (PRRS) - A Novel Ship Segmentation Method Based on Kurtosis Test in Complex-Valued SAR Imagery
摘要： Traditional ship segmentation methods in synthetic aperture radar (SAR) imagery are mainly based on the intensity/amplitude information and cannot take fully advantage of the complex information in SAR imagery. This paper proposes a novel ship segmentation method based on kurtosis test in the complex-valued SAR imagery. It can take benefit of the complex information of the SAR imagery. The segmentation rationale is that sea clutter usually obey a Gaussian distribution while ship targets usually obey a sup-Gaussian distribution. Thus, their kurtosis can be different. Kurtosis is invariant with respect to location shift and positive scale changes. It follows that kurtosis of sea clutter remains approximately constant while the amplitude decreases with the incidence angle increasing. Preliminary experimental results based on Gaofen-3 and Sentinel-1 data show that the proposed method can achieve good performance.
关键词： synthetic aperture radar (SAR),ship segmentation,kurtosis test,Gaussianity,complex-valued
更新于2025-09-04 15:30:14
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - High efficient and wide bandwidth Fresnel lens antenna at Millimeter-wave
摘要： This paper presents an efficient technique for enhancing the aperture efficiency and the bandwidth of a Fresnel lens antenna. The phase of the spherical phase front arriving from the primary source (optimized horn antenna) is smoothly compensated to improve the gain of antenna. This smoothly compensation is possible thanks to an accurate technological process allowing to obtain an infinity of dielectric constant values from a unique foam material. The manufactured lens is validated by measurement in E band with a maximum gain of 38.9dBi and with a -2dB radiation frequency bandwidth of 29GHz around 90GHz.
关键词： millimeter waves,Fresnel lens,aperture efficiency
更新于2025-09-04 15:30:14
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[Institution of Engineering and Technology 12th European Conference on Antennas and Propagation (EuCAP 2018) - London, UK (9-13 April 2018)] 12th European Conference on Antennas and Propagation (EuCAP 2018) - Wireless Detection of Moving Chipless Tags made of Metamaterial Resonators
摘要： An innovative reading procedure based on the Inverse Synthetic Aperture Radar technique aimed at improving the reliability of chipless RFID tags wireless detection is presented. More in detail, the considered scenario comprises a moving tagged item travelling along a known path. The detection scheme relies on the integration of multiple received signals and benefits from the information on the background echo, which is intrinsic to the procedure. This technique greatly enhances the detection probability in complex scenarios subject to a high level of clutter. An equivalent model for the detection procedure of chipless tags in a noisy environment is presented. Successful experimental tests of tag readings with low Signal to Noise Ratio (SNR) are illustrated.
关键词： Artificial Impedance Surface (AIS),Chipless RFID,Inverse Synthetic Aperture Radar (ISAR),Frequency Selective Surfaces (FSS)
更新于2025-09-04 15:30:14