基于Keystone变换和扰动重采样的机动平台大斜视SAR成像方法

李根; 马彦恒; 侯建强; 徐公国

doi:10.11999/JEIT190831

基于Keystone变换和扰动重采样的机动平台大斜视SAR成像方法

doi: 10.11999/JEIT190831

1.
陆军工程大学石家庄校区无人机工程系石家庄 050003
2.
陆军工程大学石家庄校区电子与光学工程系石家庄 050003

详细信息

作者简介:
李根：男，1991年生，博士生，主要从事机动平台大斜视SAR成像和压缩感知雷达成像研究

马彦恒：男，1968年生，教授，博士生导师，主要从事机动SAR成像、低小慢目标探测等方向的研究

侯建强：男，1991年生，博士生，主要从事曲线SAR 3维成像研究

徐公国：男，1990年生，博士生，主要从事雷达信号处理与传感器融合研究

通讯作者:
李根　radarlg@163.com

中图分类号: TN957.52
计量
- 文章访问数: 2089
- HTML全文浏览量: 758
- PDF下载量: 96
- 被引次数: 0
出版历程
- 收稿日期: 2019-10-28
- 修回日期: 2020-05-29
- 网络出版日期: 2020-06-04
- 刊出日期: 2020-10-13

Maneuvering Platform High-squint SAR Imaging Method Based on Keystone Transform and Perturbation Resampling

1.
Department of UAV Engineering, Army Engineering University Shijiazhuang Campus, Shijiazhuang 050003, China
2.
Department of Electronic and Optical Engineering, Army Engineering University Shijiazhuang Campus, Shijiazhuang 050003, China

摘要

摘要: 加速度和下降速度的存在使机动平台大斜视SAR的成像参数存在明显的2维空变性，严重影响场景的聚焦深度。针对这个问题，该文提出了一种基于Keystone变换和扰动重采样的机动SAR成像方法。首先，通过距离走动校正和去加速处理实现距离方位解耦以及方位频谱去混叠，然后采用方位时域的Keystone变换校正空变的距离徙动；在方位压缩过程中，通过引入时域的高阶扰动因子去除多普勒参数的2阶及3阶方位空变性，然后通过方位频域的重采样处理去除多普勒参数的方位1阶空变性。所提方法能够有效校正距离徙动轨迹和方位聚焦参数的2维空变性，实现机动平台大斜SAR的大场景成像，仿真分析验证了所提方法的有效性。
- SAR成像 /
- 大斜视 /
- 机动平台 /
- Keystone变换 /
- 扰动重采样
Abstract: The existence of acceleration and descent velocity makes the imaging parameters of high-squint SAR mounted on maneuvering platform have obvious two-dimensional spatial variability, which affects seriously the focus depth of the scene. To solve this problem, a maneuvering SAR imaging method based on Keystone transform and azimuth perturbation resampling is proposed. First of all, the range azimuth decoupling and the azimuth spectrum de Aliasing are realized by the range walk correction and de-acceleration processing. Then the spatial-variant range cell migration is corrected by the Keystone transform in the azimuth time domain; In the process of azimuth compression, the second- and third-order spatial variabilities of Doppler parameters are removed by introducing the high-order perturbation factor in the time domain, and then the first-order spatial variability of the Doppler parameters is removed by the azimuth resampling processing in the azimuth frequency domain. The proposed method can effectively correct the two-dimensional spatial variability of range cell migration trajectory and azimuth focus parameters, and realize the large scene imaging of high-squint maneuvering SAR. Simulation analysis verifies the effectiveness of the proposed method.
- SAR imaging /
- High-squint /
- Maneuvering platforms /
- Keystone transform /
- Perturbation resampling

HTML全文

图 1 机动平台大斜视SAR成像模型

下载: 全尺寸图片幻灯片

图 2 成像算法流程

下载: 全尺寸图片幻灯片

图 3 有效成像区域分析

下载: 全尺寸图片幻灯片

图 4 机动SAR成像目标分布示意图

下载: 全尺寸图片幻灯片

图 5 空变距离徙动校正结果

下载: 全尺寸图片幻灯片

图 6 点目标聚焦结果方位剖面图

下载: 全尺寸图片幻灯片

表 1 仿真参数

参数	数值	参数	数值
载频	15 GHz	地面斜视角	60°
距离带宽	300 MHz	平台高度	4 km
合成孔径时间	3 s	中心斜距	12 km
脉冲宽度	5 μs	速度	(150, 0, –30) m/s
脉冲重复频率	1.5 kHz	加速度	(2.4, 0.8, –2.2) m/s²

下载: 导出CSV

表 2 点目标方位向测量指标

测量指标	FDPF方法^[13]			本文扰动重采样方法
测量指标	点1	点2	点3	点1	点2	点3
PSLR(dB)	–3.98	–13.26	–4.78	–12.68	–13.27	–13.39
ISLR(dB)	–7.11	–9.83	–6.78	–9.37	–9.81	–10.28
MW	20.67	15.60	28.35	15.62	15.61	15.62

下载: 导出CSV

参考文献(16)

ZENG Tao, LI Yinghe, DING Zegang, et al. Subaperture approach based on azimuth-dependent range cell migration correction and azimuth focusing parameter equalization for maneuvering high-squint-mode SAR[J]. IEEE Transactions on Geoscience and Remote Sensing, 2015, 53(12): 6718–6734. doi: 10.1109/TGRS.2015.2447393

DANG Yanfeng, LIANG Yi, BIE Bowen, et al. A range perturbation approach for correcting spatially variant range envelope in diving highly squinted SAR with nonlinear trajectory[J]. IEEE Geoscience and Remote Sensing Letters, 2018, 15(6): 858–862. doi: 10.1109/LGRS.2018.2812158

LIAO Yi, ZHOU Song, and YANG Lei. Focusing of SAR with curved trajectory based on improved hyperbolic range equation[J]. IEEE Geoscience and Remote Sensing Letters, 2018, 15(3): 454–458. doi: 10.1109/LGRS.2018.2794471

李宁, 别博文, 邢孟道, 等. 基于多普勒重采样的恒加速度大斜视SAR成像算法[J]. 电子与信息学报, 2019, 41(12): 2873–2880. doi: 10.11999/JEIT180953

LI Ning, BIE Bowen, XING Mengdao, et al. A doppler resampling based imaging algorithm for high squint SAR with constant acceleration[J]. Journal of Electronics &Information Technology, 2019, 41(12): 2873–2880. doi: 10.11999/JEIT180953

LI Zhenyu, LIANG Yi, XING Mengdao, et al. An improved range model and Omega-k-based imaging algorithm for high-squint SAR with curved trajectory and constant acceleration[J]. IEEE Geoscience and Remote Sensing Letters, 2016, 13(5): 656–660. doi: 10.1109/LGRS.2016.2533631

邓欢, 李亚超, 梅海文, 等. 弹载曲线轨迹双基SAR反向滤波PFA成像与图像畸变校正算法[J]. 电子与信息学报, 2018, 40(11): 2638–2644. doi: 10.11999/JEIT170994

DENG Huan, LI Yachao, MEI Haiwen, et al. New back-filtering PFA imaging algorithm and distortion correction method for missile-borne bistatic SAR with curved track[J]. Journal of Electronics &Information Technology, 2018, 40(11): 2638–2644. doi: 10.11999/JEIT170994

江淮, 赵惠昌, 汉敏, 等. 基于变量解耦的俯冲加速段弹载SAR大场景成像算法[J]. 物理学报, 2014, 63(7): 078403. doi: 10.7498/aps.63.078403

JIANG Huai, ZHAO Huichang, HAN Min, et al. An imaging algorithm for missile-borne SAR with downward movement based on variable decoupling[J]. Acta Physica Sinica, 2014, 63(7): 078403. doi: 10.7498/aps.63.078403

LI Zhenyu, XING Mengdao, LIANG Yi, et al. A frequency-domain imaging algorithm for highly squinted SAR mounted on maneuvering platforms with nonlinear trajectory[J]. IEEE Transactions on Geoscience and Remote Sensing, 2016, 54(7): 4023–4038. doi: 10.1109/TGRS.2016.2535391

江淮, 陈思, 赵惠昌, 等. 一种弹载SAR子孔径成像算法[J]. 电子与信息学报, 2017, 39(10): 2526–2530. doi: 10.11999/JEIT161337

JIANG Huai, CHEN Si, ZHAO Huichang, et al. Subaperture imaging algorithm for missile-borne SAR[J]. Journal of Electronics &Information Technology, 2017, 39(10): 2526–2530. doi: 10.11999/JEIT161337

刘文康, 景国彬, 孙光才, 等. 基于两步方位重采样的中轨SAR聚焦方法[J]. 电子与信息学报, 2019, 41(1): 136–142. doi: 10.11999/JEIT180238

LIU Wenkang, JING Guobin, SUN Guangcai, et al. Medium-earth-orbit SAR data focusing method based on two-step azimuth resampling[J]. Journal of Electronics &Information Technology, 2019, 41(1): 136–142. doi: 10.11999/JEIT180238

TANG Shiyang, LIN Chunhui, ZHOU Yu, et al. Processing of long integration time spaceborne SAR data with curved orbit[J]. IEEE Transactions on Geoscience and Remote Sensing, 2018, 56(2): 888–904. doi: 10.1109/TGRS.2017.2756109

别博文, 梁毅, 党彦锋, 等. 曲线轨迹SAR大斜视子孔径成像算法[J]. 系统工程与电子技术, 2017, 39(3): 500–505. doi: 10.3969/j.issn.1001-506X.2017.03.07

BIE Bowen, LIANG Yi, DANG Yanfeng, et al. Sub-aperture imaging algorithm for high squint SAR with curvilinear flight tracks[J]. Systems Engineering and Electronics, 2017, 39(3): 500–505. doi: 10.3969/j.issn.1001-506X.2017.03.07

党彦锋, 梁毅, 别博文, 等. 俯冲段大斜视SAR子孔径成像二维空变校正方法[J]. 电子与信息学报, 2018, 40(11): 2621–2629. doi: 10.11999/JEIT180021

DANG Yanfeng, LIANG Yi, BIE Bowen, et al. Two-dimension space-variance correction approach for diving highly squinted SAR imaging with sub-aperture[J]. Journal of Electronics &Information Technology, 2018, 40(11): 2621–2629. doi: 10.11999/JEIT180021

NEO Y L, WONG F, and CUMMING I G. A two-dimensional spectrum for bistatic SAR processing using series reversion[J]. IEEE Geoscience and Remote Sensing Letters, 2007, 4(1): 93–96. doi: 10.1109/LGRS.2006.885862

LI Dong, LIN Huan, LIU Hongqing, et al. Focus improvement for high-resolution highly squinted SAR imaging based on 2-D spatial-variant linear and quadratic RCMs correction and azimuth-dependent doppler equalization[J]. IEEE Journal of Selected Topics in Applied Earth Observations and Remote Sensing, 2017, 10(1): 168–183. doi: 10.1109/jstars.2016.2569561

TANG Shiyang, ZHANG Linrang, GUO Ping, et al. Processing of monostatic SAR data with general configurations[J]. IEEE Transactions on Geoscience and Remote Sensing, 2015, 53(12): 6529–6546. doi: 10.1109/TGRS.2015.2443835

施引文献

资源附件(0)

访问统计