Space-variant Phase Compensation and Focusing Processing of High-speed Diving 3D Linear Array SAR

doi:10.12382/bgxb.2024.0596

Abstract

Abstract:

The combination of 3D linear array synthetic aperture radar (SAR) and high-speed platform can achieve imaging in extreme scenarios.To achieve imaging under this SAR system with high-speed platform,it is necessary to overcome the more complex range migration and space-variant characteristics caused by high speed and large acceleration.This paper proposes an echo signal model and a slant range model suitable for 3D linear array SAR on high-speed platform,and uses the implicit function derivation method to achieve the acquisition of 3D frequency spectrum.To balance the azimuth and cross-track space-variant modulated phases,the least squares fitting method is employed for two-dimensional resampling operations in the azimuth and cross-track directions for completing the compensation for space-variant phase errors in these two dimensions.The proposed compensation algorithm based on least squares fitting can effectively eliminates the impact of space-variant phase errors on imaging,thereby enhancing the imaging performance of 3D linear array SAR in high-speed scenarios.Finally,the effectiveness of the proposed algorithm is verified through simulation experiment.

Key words: synthetic aperture radar, 3D linear array, forward looking imaging, high speed platform, space-variant phase error compensation, least squares fitting

CLC Number:

V243.2

LIU Can, TAN Gewei. Space-variant Phase Compensation and Focusing Processing of High-speed Diving 3D Linear Array SAR[J]. Acta Armamentarii, 2025, 46(6): 240596-.

Figures/Tables 8

References 24

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参数	数值
载频f_c/GHz	20
发射信号带宽B_r/MHz	120
脉冲宽度T_r/μs	1.5
平台高度H/m	4500
雷达初始速度v=(v_x,0,v_z)/(m·s^-1)	(400,0,100)
加速度a=(a_x,0,a_z)/(m·s^-2)	(20,0,10)
天线间隔d/m	0.15

参数	数值
载频f_c/GHz	20
发射信号带宽B_r/MHz	120
脉冲宽度T_r/μs	1.5
平台高度H/m	4500
雷达初始速度v=(v_x,0,v_z)/(m·s^-1)	(400,0,100)
加速度a=(a_x,0,a_z)/(m·s^-2)	(20,0,10)
天线间隔d/m	0.15

方向	参数	文献[14]算法			文献[17]算法			本文算法
方向	参数	P0	P1	P2	P0	P1	P2	P0	P1	P2
距离向	PSLR/dB	-11.35	-14.35	-	-12.30	-11.55	-12.22	-12.59	-12.69	-13.02
	ISLR/dB	-10.64	-12.56	-	-10.36	-10.25	-9.81	-9.93	-10.09	-10.88
	IRW/m	1.91	2.32	2.98	1.76	1.76	1.88	1.14	1.30	1.30
方位向	PSLR/dB	-8.65	-13.86	-5.68	-13.02	-10.69	-11.87	-12.12	-12.70	-12.76
	ISLR/dB	-11.84	-12.64	-	-10.28	-13.64	-10.84	-9.58	-10.07	-10.01
	IRW/m	2.06	2.39	2.87	1.88	2.02	1.95	1.29	1.36	1.29
跨航向	PSLR/dB	-11.02	-12.68	-10.65	-11.68	-10.18	-10.88	-12.32	-11.25	-12.23
	ISLR/dB	-8.65	-8.96	-9.02	-9.69	-8.72	-8.50	-10.58	-10.87	-9.77
	IRW/m	2.06	2.17	2.13	1.80	1.80	1.84	1.32	1.25	1.25

方向	参数	文献[14]算法			文献[17]算法			本文算法
方向	参数	P0	P1	P2	P0	P1	P2	P0	P1	P2
距离向	PSLR/dB	-11.35	-14.35	-	-12.30	-11.55	-12.22	-12.59	-12.69	-13.02
	ISLR/dB	-10.64	-12.56	-	-10.36	-10.25	-9.81	-9.93	-10.09	-10.88
	IRW/m	1.91	2.32	2.98	1.76	1.76	1.88	1.14	1.30	1.30
方位向	PSLR/dB	-8.65	-13.86	-5.68	-13.02	-10.69	-11.87	-12.12	-12.70	-12.76
	ISLR/dB	-11.84	-12.64	-	-10.28	-13.64	-10.84	-9.58	-10.07	-10.01
	IRW/m	2.06	2.39	2.87	1.88	2.02	1.95	1.29	1.36	1.29
跨航向	PSLR/dB	-11.02	-12.68	-10.65	-11.68	-10.18	-10.88	-12.32	-11.25	-12.23
	ISLR/dB	-8.65	-8.96	-9.02	-9.69	-8.72	-8.50	-10.58	-10.87	-9.77
	IRW/m	2.06	2.17	2.13	1.80	1.80	1.84	1.32	1.25	1.25