| 引用本文: | 周子铂，王鑫奎，蔡万勇，刘建卫，张朝伟. 联合时频分析和谱估计的机动目标ISAR成像[J]. 雷达科学与技术, 2021, 19(4): 393-402.[点击复制] |
| ZHOU Zibo, WANG Xinkui, CAI Wanyong, LIU Jianwei, ZHANG Chaowei. Joint Time-Frequency Analysis and Super-Resolution ISAR Imaging for Targets with Complex Motion[J]. Radar Science and Technology, 2021, 19(4): 393-402.[点击复制] |
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| 摘要: |
| 机动目标逆合成孔径雷达（Inverse Synthetic Aperture Radar, ISAR）成像中，在对目标回波进行平动补偿之后，每一个包含目标散射点的距离单元的回波都可以表示为多分量的线性调频信号。鉴于机动目标散射点多普勒频率的时变特性，传统的距离 多普勒（Range Doppler, RD）算法获得的机动目标ISAR图像是模糊的。本文提出一种联合短时傅里叶变换（Short Time Fourier Transform, STFT）和多重信号分类（Multiple Signal Classification, MUSIC）谱估计的方法来克服目标机动对成像的影响，首先利用STFT截取部分信号以降低较长时间内目标机动对成像的影响，然后通过MUSIC谱估计算法克服“不确定”原则对STFT分辨率的限制，从而获得高分辨的机动目标ISAR图像。最后，通过散射点模型仿真和波音B727实测数据验证本文所提方法的有效性。 |
| 关键词: 逆合成孔径雷达 机动目标 时频分析 短时傅里叶变换 谱估计 |
| DOI：DOI:10.3969/j.issn.1672-2337.2021.04.005 |
| 分类号:TN958 |
| 基金项目: |
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| Joint Time-Frequency Analysis and Super-Resolution ISAR Imaging for Targets with Complex Motion |
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ZHOU Zibo, WANG Xinkui, CAI Wanyong, LIU Jianwei, ZHANG Chaowei
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1.Air Force Early Warning Academy，Wuhan 430019, China;2.Unit 63696 of PLA，Jiangyin 214400, China
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| Abstract: |
| In inverse synthetic aperture radar (ISAR) imaging for target with complex motion, after motion compensation, the azimuth echoes of a certain range cell can be modeled as multi-component linear frequency modulation (LFM) signals. In view of the time-varying character of Doppler frequencies of each scatterer, the obtained ISAR image by traditional range Doppler (RD) algorithm is blurred. To solve this problem, this paper proposes a novel imaging method by combining the short time Fourier transform (STFT) and space spectrum estimation to overcome the effect of complex motion and obtain high-resolution ISAR image. Firstly, STFT is utilized to intercept a part of the signal and reduce the coherent time, then the multiple signal classification (MUSIC) method is implemented to overcome the resolution constrain of ‘Uncertainty’ principle to acquire the super-resolution ISAR image. The simulation data and Boeing B727 measurement data verify the effectiveness of the proposed method. |
| Key words: sinverse synthetic aperture radar complex motion time-frequency analysis short time Fourier transform spectrum estimation |
