基于级数反演的双基前视高机动平台SAR成像算法

doi:10.16180/j.cnki.issn1007-7820.2019.09.014

摘要/Abstract

摘要：

双基前视高机动平台合成孔径雷达BFHM-SAR是一种新型合成孔径雷达成像模式,可实现高机动平台末端俯冲阶段全程二维高分辨成像。由于BFHM-SAR中收发平台沿曲线轨迹运动且均具有较大的速度和加速度,导致双基距离历程中存在双根号下高阶项的问题。此外,该构型相较于单/双基直线轨迹SAR,存在更为严重的距离徙动问题。针对上述缺陷,文中首先在时域对距离走动量进行校正以减少二维耦合量,然后在斜距精确高阶近似的基础上结合级数反演思想推导出信号的二维频谱,在距离频域-方位多普勒域进行剩余的距离走动和距离弯曲的校正,最后完成二维脉冲压缩,在实现高分辨成像。文中对该构型下特殊的方位向聚焦深度的问题也进行了具体分析,仿真实验结果验证了成像算法的正确性和可行性。

关键词: 合成孔径雷达, 双基前视, 高机动平台, 距离徙动, 聚焦深度, 级数反演

Abstract:

BFHM-SAR is a new and special imaging mode, which performs 2D imaging during the whole terminal diving period of high speed maneuvering platform. In the BFHM-SAR, the transceiver platform moves along different curve trajectories and has great velocities and accelerations, which leads to the problem of high-order terms under the double root and more serious range cell migration in the double-base distance history. In addition, this configuration has a more serious distance migration problem than monostatic or bistatic SAR. This study firstly corrected the range walk in time domain to reduce the two dimensional coupling, and then derived the two-dimensional frequency spectrum by the method of series reversion based on the accurate approximation of slant range in high order. The remaining rang cell curvature was corrected in range frequency azimuth Doppler domain and the high resolution imaging was completed after the pulse compression in both range and azimuth directions. In addition, focus depth in azimuth direction in this special configuration was analyzed in detail. Finally, the validity and feasibility of the proposed approach were verified with the simulation results.

Key words: synthetic aperture radar, bistatic forward-looking, high speed maneuvering platform, range cell migration, focus depth, series reversion

中图分类号:

TN957

张爱丽,孟自强. 基于级数反演的双基前视高机动平台SAR成像算法[J]. 电子科技, 2019, 32(9): 65-71.

ZHANG Aili,MENG Ziqiang. Imaging Method for Bistatic Forward-Looking High-speed Maneuvering-platform SAR Based on Series Reversion[J]. Electronic Science and Technology, 2019, 32(9): 65-71.

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参考文献 16

[1]	毕开波, 杨兴宝, 陆永红 . 导弹武器及其制导技术[M]. 北京: 国防工业出版社, 2013.
	Bi Kaibo, Yang Xingbao, Lu Yonghong. Missile weapon and guidance technology[M]. Beijing: National Defence Industry Press, 2013.
[2]	秦玉亮, 王建涛, 王宏强 , 等. 弹载合成孔径雷达技术研究综述[J]. 信号处理, 2009,25(4):630-635.
	Qin Yuliang, Wang Jiantao , Wang Hongqiang,el at.Overview on missile-borne synthetic aperture radar[J]. Signal Processing, 2009,25(4):630-635.
[3]	杨立波, 任笑真, 杨汝良 . 末制导合成孔径雷达信号分析及成像处理[J]. 系统工程与电子技术, 2010,32(6):1176-1181. doi: 10.3969/j.issn.1001-506X.2010.06.015
	Yang Libo, Ren Xiaozhen, Yang Ruliang . Signal analysis and imaging processing of terminal guidance synthetic aperture radar[J]. Systems Engineering and Electronic, 2010,32(6):1176-1181. doi: 10.3969/j.issn.1001-506X.2010.06.015
[4]	Espeter T, Walterscheid I, Klare J , et al. Bistatic forward-looking SAR:results of a spaceborne-airborne experiment[J]. IEEE Geoscience and Remote Sensing Letters, 2011,8(4):765-768.
[5]	Wu Junjie, Huang Yulin, Yang Jianyu, et al. First result of bistatic forward-looking SAR with stationary transmitter [C].Vancouver:Proceedings of IEEE International Geoscience and Remote Sensing Symposium, 2011.
[6]	Cumming I G, Wong F H . Digital processing of synthetic aperture radar data: algorithms and implementation[M]. Norwood:Artech House, 2004.
[7]	周松, 周鹏, 李亚超 , 等. 弹载SAR下降段成像算法研究[J]. 西安电子科技大学学报, 2011,38(3):90-98.
	Zhou Song, Zhou Peng, Li Yachao , et al. Research on the imaging algorithm for missile-borne SAR with downward movement[J]. Journal of Xidian University, 2011,38(3):90-98.
[8]	彭岁阳, 卢大威, 张军 , 等. 时域校正距离走动的CS成像算法[J]. 西安电子科技大学学报, 2010,26(7):1115-1120.
	Peng Suiyang, Lu Dawei, Zhang Jun , et al. The chirp scaling imaging algorithm with range walk correction in time domain[J]. Journal of Xidian University, 2010,26(7):1115-1120.
[9]	Neo Y L, Wong F H, Cumming I G . A two-dimensional spectrum for bisstatic SAR processing using series reversion[J]. IEEE Geoscience and Remote Sensing Letters, 2007,4(1):93-96.
[10]	Wu Junjie, Li Zhongyu, Huang Yulin , et al. Focusing bistatic forward-looking SAR with stationary transmitter based on keystone transform and nonlinear chirp scaling[J]. IEEE Geoscience and Remote Sensing Letters, 2014,11(1):148-152.
[11]	Ma C, Gu H, Su W , et al. Focusing one-stationary bistatic forward looking synthetic aperture radar with squint minimisation method[J]. IET Radar, Sonar & Navigation, 2015,9(8):927-932.
[12]	Qiu Xiaolan, Hu Donghui, Ding Chibiao . Some reflections on bistatic SAR of forward-looking configuration[J]. IEEE Geoscience and Remote Sensing Letters, 2008,5(4):735-739.
[13]	Yang J, Huang Y, Yang H , et al. A first experiment of airborne bistatic forward-looking SAR-Preliminary results[C].Melbourne:Proceedings of IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 2013.
[14]	Wang X, Zhu D, Zhu Z . Research on the Bistatic forward-looking SAR imaging[J]. Journal of Electronics (China), 2010,27(6):735-741.
[15]	Espeter T, Walterscheid I, Klare J , et al. Bistatic forward-looking SAR:results of a spaceborne-airborne experiment[J]. IEEE Geoscience and Remote Sensing Letters, 2011,8(4):765-768.
[16]	Liu Zhe, Yang Jianyu, Zhang Xiaoling . Nonlinear RCM compensation method for spaceborne/airborne forward-looking bistatic SAR [C].Vancouver:Proceedings of IEEE International Geoscience and Remote Sensing Symposium, 2011.

参数	数值	参数	数值	参数	数值
λ/m	0.02	PRF/kHz	6	v_t'₀/m·s^-1	(0,1 800,-200)
B/MHz	100	ψ/(°)	20	a_t'/m·s^-2	(0,-35,15)
F_s/MHz	150	H_T/km	16	v_r₀/m·s^-1	(0,1 500,-150)
T_p/μs	2	H_R/km	15	a_r/m·s^-2	(0,-25,10)

参数	方位向			距离向
参数	PSLR/dB	ISLR/dB	分辨率/m	PSLR/dB	ISLR/dB	分辨率/m
目标点A	-13.00	-9.88	0.83	-13.28	-10.15	2.75
中心点P_c	-13.26	-10.14	0.82	-13.25	-10.14	2.75
目标点B	-13. 40	-9.92	0.85	-13.24	-10.12	2.75