- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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[IEEE 2018 IEEE Conference on Antenna Measurements & Applications (CAMA) - Va?ster?s (2018.9.3-2018.9.6)] 2018 IEEE Conference on Antenna Measurements & Applications (CAMA) - A Novel Technique of Broadband Circularly Polarized Microstrip Antenna Development withSquare Ring Slot for SAR Application
摘要： This paper presents a novel technique to develop a broadband circularly polarized microstrip antenna by using square ring slot for SAR application. The minimum requirements of proposed antenna are 800MHz bandwidth with the resonant frequency at 9.4GHz and workable in circular polarization. To satisfy a broadband bandwidth characteristic, a novel technique, called as SRS technique, is implemented upon the patch radiator. The proposed antenna is designed to produce the left-handed circular polarization (LHCP). It is etched on double layer of NPC-H22A dielectric substrate with the dielectric constant of 2.17 and the thickness of 1.6mm. By implementing SRS technique on the proposed antenna, the bandwidth of axial ratio achieved of 12.7% (8.7GHz–9.9GHz), the impedance bandwidth of 36% (8.5GHz–11.9GHz), and the gain achievement up to 6dBic.
关键词： LHCP,microstrip antenna,spaceborne SAR.,Broadband,Synthetic Aperture Radar (SAR)
更新于2025-09-04 15:30:14
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[IEEE 2018 China International SAR Symposium (CISS) - Shanghai, China (2018.10.10-2018.10.12)] 2018 China International SAR Symposium (CISS) - Inverse Synthetic Aperture Ladar Demonstration and Outdoor Experiments
摘要： Inverse synthetic aperture ladar(ISAL)operates at light wavelength and utilizes the synthetic aperture technique, which can obtain very high resolution two-dimensional or three dimensional image of a moving target and thus have many important applications for target detection and recognition. With a very short wavelength, 10000 times smaller compared with that of microwave radar, ISAL can get a high angle resolution with a small telescope in microseconds. However, ISAL is more sensitive to many errors, such as ladar vibration, atmospheric turbulence, moving target jitter, etc., which bring many difficulties to implement an ISAL equipment. In this article, we present an ISAL demonstration and some outdoor experimental results. The ISAL transmits wideband coherent laser which is created by modulating a phase coded signal onto a continuous laser waveform at 1550nm, and detects weak echoes reflected from moving targets by a coherent detection system. A modified phased gradient autofocus algorithm(MPGA)is utilized to suppress errors and improve image quality. The ISAL demonstration acquires high-resolution images of 3-centimeter with a distance about 200m.
关键词： Inverse Synthetic Aperture Ladar,Phased Gradient Autofocus,High-resolution Imaging
更新于2025-09-04 15:30:14
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[IEEE 2018 China International SAR Symposium (CISS) - Shanghai, China (2018.10.10-2018.10.12)] 2018 China International SAR Symposium (CISS) - A New Method of Phase-Perturbed LFM Chirp Signals for SAR ECCM
摘要： The active coherent jamming based on Digital Radio Frequency Memory (DRFM) is an effective method of jamming for synthetic aperture radar (SAR). The traditional linear frequency modulated signal (LFM) signal synthetic aperture radar has poor capability of counting active coherent jamming. In this paper, a new SAR signal based on phase- perturbed LFM (PPLFM) signal was proposed to improve the ability of radar to resist active coherent jamming. First, the design method of PPLFM signal is presented, after which the disturbance amplitude matrix is optimized. Then the electronic counter countermeasures (ECCM) performance and imaging performance of the PPLFM signal are analyzed with different disturbance parameters. Finally, the ability to suppress false target jamming and frequency shift jamming is compared with the LFM signal. Simulation results show that the PPLFM signal can effectively suppress the active coherent jamming compared with the LFM signal.
关键词： Electronic Counter Countermeasures (ECCM),Pulse diversity,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 (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Registration of SAR and Optical Images by Weighted Sift Based on Phase Congruency
摘要： In this paper, to address problems in the registration of synthetic aperture radar (SAR) and optical images due to large gray differences, the scale-invariant feature transform (SIFT) approach based on phase congruency (PC-SIFT) is proposed. This approach is used to address the gradient inversion in multi-source images, and it is based on optimizing the dominant direction interval of the descriptors. We construct a new descriptor by combining phase consistency and the gradient amplitude, which is referred to as PCG-SIFT descriptor. The proposed algorithm is suitable for multi-sensor images with large gray differences and significant edge features The results of experiments show that compared to the traditional gradient-based SIFT descriptor, the PC-SIFT descriptor and PCG-SIFT descriptor improve the robustness and matching probability of the registration algorithm for multi-source images.
关键词： scale invariant feature transform,optical image,image registration,synthetic aperture radar
更新于2025-09-04 15:30:14
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Polarimetric Convolutional Network for PolSAR Image Classification
摘要： The approaches for analyzing the polarimetric scattering matrix of polarimetric synthetic aperture radar (PolSAR) data have always been the focus of PolSAR image classification. Generally, the polarization coherent matrix and the covariance matrix obtained by the polarimetric scattering matrix are used as the main research object to extract features. In this paper, we focus on the original polarimetric scattering matrix and propose a polarimetric scattering coding way to deal with polarimetric scattering matrix and obtain a close complete feature. This encoding mode can also maintain polarimetric information of scattering matrix completely. At the same time, in view of this encoding way, we design a corresponding classification algorithm based on the convolution network to combine this feature. Based on the polarimetric scattering coding and convolution neural network, the polarimetric convolutional network is proposed to classify PolSAR images by making full use of polarimetric information. We perform the experiments on the PolSAR images acquired by AIRSAR and RADARSAT-2 to verify the proposed method. The experimental results demonstrate that the proposed method get better results and has huge potential for PolSAR data classification. Source code for polarimetric scattering coding is available at https://github.com/liuxuvip/Polarimetric-Scattering-Coding.
关键词： convolution network,polarimetric synthetic aperture radar (PolSAR),Classification,polarimetric scattering matrix
更新于2025-09-04 15:30:14
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SAR Automatic Target Recognition Using a Roto-Translational Invariant Wavelet-Scattering Convolution Network
摘要： The algorithm of synthetic aperture radar (SAR) for automatic target recognition consists of two stages: feature extraction and classification. The quality of extracted features has significant impacts on the final classification performance. This paper presents a SAR automatic target classification method based on the wavelet-scattering convolution network. By introducing a deep scattering convolution network with complex wavelet filters over spatial and angular variables, robust feature representations can be extracted across various scales and angles without training data. Conventional dimension reduction and a support vector machine classifier are followed to complete the classification task. The proposed method is then tested on the moving and stationary target acquisition and recognition (MSTAR) benchmark data set and achieves an average accuracy of 97.63% on the classification of ten-class targets without data augmentation.
关键词： automatic target classification (ATR),wavelet transform,scattering convolution network,roto-translation invariance,synthetic aperture radar
更新于2025-09-04 15:30:14