微波视觉三维SAR关键技术及实验系统初步进展

仇晓兰; 焦泽坤; 杨振礼; 程遥; 蔺蓓; 罗一通; 王卫; 董勇伟; 周良将; 丁赤飚

doi:10.12000/JR22027

微波视觉三维SAR关键技术及实验系统初步进展

DOI: 10.12000/JR22027

仇晓兰^{1, 2, 3, 4, ,},
焦泽坤^{1, 4},
杨振礼⁵,
程遥^{2, 3},
蔺蓓^{2, 3},
罗一通^{2, 3},
王卫^{2, 3},
董勇伟⁵,
周良将^{1, 4},
丁赤飚^{1, 4, ,}

1.
微波成像技术国家级重点实验室北京 100190
2.
苏州市空天大数据智能应用技术重点实验室苏州 215123
3.
苏州空天信息研究院苏州 215123
4.
中国科学院空天信息创新研究院北京 100190
5.
中科宇达(北京)科技有限公司北京 100190

基金项目: 国家自然科学基金(61991420, 61991421, 61991424)

详细信息

作者简介:
仇晓兰(1982–)，女，中国科学院空天信息创新研究院研究员，博士生导师。主要研究方向为SAR成像处理、SAR图像理解。担任IEEE高级会员、IEEE地球科学与遥感快报副主编、雷达学报青年编委

焦泽坤(1991–)，男，博士，中国科学院空天信息创新研究院助理研究员。研究方向为SAR三维成像技术

丁赤飚(1969–)，男，研究员，博士生导师，中国科学院院士。主要研究方向为合成孔径雷达、遥感信息处理和应用系统等，先后主持多项国家863重点项目和国家级遥感卫星地面系统工程建设等项目，曾获国家科技进步一等奖、二等奖，国家技术发明二等奖等

通讯作者:
仇晓兰 xlqiu@mail.ie.ac.cn

丁赤飚 cbding@mail.ie.ac.cn

责任主编：张群 Corresponding Editor: ZHANG Qun
中图分类号: TN957.52
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- 被引次数: 0
出版历程
- 收稿日期: 2022-01-29
- 修回日期: 2022-02-17
- 网络出版日期: 2022-02-24
- 刊出日期: 2022-02-28

Key Technology and Preliminary Progress of Microwave Vision 3D SAR Experimental System

QIU Xiaolan^{1, 2, 3, 4
, ,},
JIAO Zekun^{1, 4},
YANG Zhenli⁵,
CHENG Yao^{2, 3},
LIN Bei^{2, 3},
LUO Yitong^{2, 3},
WANG Wei^{2, 3},
DONG Yongwei⁵,
ZHOU Liangjiang^{1, 4},
DING Chibiao^{1, 4
, ,}

1.
National Key Lab of Microwave Imaging Technology, Beijing 100190, China
2.
Key Laboratory of Intelligent Aerospace Big Data Application Technology, Suzhou 215123, China
3.
Suzhou Aerospace Information Research Institute, Suzhou 215123, China
4.
Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China
5.
Zhongke Yuda (Beijing) Technology Co., Ltd., Beijing 100190, China

Funds: The National Natural Science Foundation of China (61991420, 61991421, 61991424)

More Information

Corresponding author: QIU Xiaolan, xlqiu@mail.ie.ac.cn; DING Chibiao, cbding@mail.ie.ac.cn

摘要

摘要: 合成孔径雷达(SAR)三维成像在复杂地形测绘、复杂环境下目标发现与识别等方面具有重要应用潜力，是当前SAR领域的重要发展方向之一。为推动SAR三维成像技术的发展和应用，中国科学院空天信息创新研究院牵头设计并研制了一套无人机载微波视觉三维SAR实验系统(MV3DSAR)，为相关技术研究和验证提供实验平台。目前该系统的单极化版本已研制完成，并在天津开展了首次校飞实验。该文介绍了该系统的基本构成、主要性能以及系统和数据处理的关键技术，给出了首次校飞实验的实施情况以及初步的数据处理结果，验证了系统的基本性能指标和三维成像能力。该系统为后续SAR三维成像数据集构建和处理方法研究提供了良好的实验验证平台。
- SAR三维成像 /
- 微波视觉 /
- 无人机载SAR /
- 干涉定标 /
- 运动补偿
Abstract: Three-Dimensional (3D) Synthetic Aperture Radar (SAR) imaging has considerable application potential in steep-terrain mapping and target recognition in complex environments and is an important development direction in the current SAR field. To promote the development and application of the 3D SAR imaging technology, the Aerospace Information Research Institute, Chinese Academy of Sciences designed and developed an unmanned aerial vehicle-borne Microwave-Vision 3D SAR (MV3DSAR) experimental system, which provides an experimental platform for the research and verification of related technologies. Currently, the single-polarization version of the system has been developed, and the first flight experiment has been conducted in Tianjin. This study introduces the structure, performance, key technologies, and data processing of the system. This study also presents the implementation and preliminary data processing results of the first experiment, verifying the basic performance and 3D imaging capability of the system. The MV3DSAR provides a good experimental and verification platform for analyzing 3D SAR imaging algorithms and constructing 3D SAR imaging datasets.
- SAR 3D imaging /
- Microwave vision /
- UAV borne SAR /
- InSAR calibration /
- Motion compensation

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图 1 MV3DSAR载荷示意图及实物图

Figure 1. Schematic illustration and a photo of MV3DSAR payload

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图 2 MV3DSAR系统照片

Figure 2. MV3DSAR system photo

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图 3 通道间相位差异实验室测量结果

Figure 3. Laboratory measurements of phase difference between channels

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图 4 天津临港商务大厦光学影像及照片

Figure 4. Optical image of Tianjin Lingang Business Building

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图 5 MV3DSAR校飞实验基线设计

Figure 5. Baseline design of MV3DSAR flight experiment

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图 6 观测矩阵互相关特性及空间模糊函数曲线

Figure 6. Cross-correlation properties of observation matrix and spatial ambiguity function curve

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图 7 最大不模糊高度及瑞利分辨率

Figure 7. Maximum unblurred height and Rayleigh resolution

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图 8 MV3DSAR飞行航迹设计

Figure 8. MV3DSAR flight path design

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图 9 定标器布设示意图及现场照片

Figure 9. Schematic illustration and photos of the calibrators

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图 10 激光点云结果

Figure 10. Results of Lidar point cloud

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图 11 光学倾斜摄影结果

Figure 11. Optical oblique photography results

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图 12 MV3DSAR数据处理总体流程

Figure 12. The overall flow of MV3DSAR data processing

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图 13 航迹与参考匀速直线航迹的偏离程度

Figure 13. Difference between actual flight path and reference track

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图 14 姿态测量数据随时间的变化曲线

Figure 14. Variation curve of attitude measurement data with time

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图 15 天线相位中心相对位置关系测量示意图

Figure 15. Schematic diagram of the relative position of the antenna phase center

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图 16 龙伯球和三面角反射器点目标曲线

Figure 16. Luneburg-Lens reflector and trihedral corner reflector point target curve

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图 17 8个方向临港商务大厦区域成像结果

Figure 17. Imaging results of Lingang Business Building in eight directions

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图 18 斜距误差随距离向的变化曲线

Figure 18. Variation curve of slope distance error with distance direction

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图 19 接收通道间相位误差与距离向的关系

Figure 19. The relationship between the phase error of the receiving channels and the slant range

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图 20 发射通道间相位误差与距离向的关系

Figure 20. The relationship between phase error of the transmit channels and the slant range

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图 21 发射通道间相位误差与拟合直线的偏差

Figure 21. Deviation of phase error between transmit channels and the fitted straight line

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图 22 相干系数统计曲线

Figure 22. The statistical curve of coherence coefficient

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图 23 相干系数图

Figure 23. Coherence coefficient map

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图 24 去平地后的干涉相位图

Figure 24. Interferometric phase diagram after removing flat-ground phase

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图 25 SAR图像建筑几何结构分割结果

Figure 25. Segmentation results of building geometry in SAR image

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图 26 重建三维点云解模糊前后结果对比图

Figure 26. Comparison of results before and after 3D point cloud deblurring

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图 27 临港商务大厦三维重建结果

Figure 27. 3D reconstruction results of Lingang Business Building

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图 28 临港商务大厦SAR三维成像点云与激光点云

Figure 28. SAR 3D reconstruction results and Lidar point cloud of Lingang Business Building

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表 1 MV3DSAR系统总体构成

Table 1. The overall composition of the MV3DSAR system

序号	名称	说明
1	微小型 Ku-SAR	Ku-波段SAR系统由雷达主机、天线及天线支架、开关组合、数据存储模块等组成
2	无人机平台	采用KWT-X6L-15六旋翼无人机，最大作业载荷15 kg、最大翼展尺寸2.53 m，最大飞行速度15 m/s
3	导航系统	由GPS模块和微型惯性测量单元(MIMU)模块组成；航迹测量精度0.05 m，姿态测量精度0.02°

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表 2 Ku-SAR载荷参数

Table 2. Parameters of Ku-SAR payload

序号	参数名称	参数值
1	中心频率	15.2 GHz
2	信号形式	调频连续波(FMCW)
3	极化方式	HH(后续将扩展全极化)
4	信号带宽	1200 MHz
5	天线尺寸(单通道)	0.05 m(俯仰)×0.32 m(方位)
6	每个极化的阵列通道数	4
7	分辨率	优于0.2 m×0.2 m
8	通道相位不平衡稳定度	±5° (10 min内)
9	通道幅度不平衡稳定度	±0.2 dB (10 min内)
10	中心视角	45°
11	NESZ	不大于–30 dB (最远作用距离3.6 km)
12	天线最小间隔	0.107 m
13	天线最大间隔	1.284 m
14	Ku-SAR重量	主机、存储、电池、天线、结构等一共7.07 kg

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表 3 MV3DSAR校飞实验基线长度

Table 3. Baseline length of MV3DSAR flight experiment

模式	等效天线相位中心	说明
模式1	[0, 0.107, 0.428, 0.535] m	不均匀，最短基线小，总基线较短
模式2	[0, 0.214, 0.535, 0.749] m	较均匀，最短基线较大，总基线较长

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表 4 天线相位中心相对位置

Table 4. Relative position of antenna phase center

模式1	T	R2	R1	T2	T1
X (mm)	0	–818.14	–603.95	–389.86	465.86
Y (mm)	0	27.95	24.27	20.04	3.92
Z (mm)	0	–109.18	–109.53	–110.0	–110.40

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表 5 定标器分辨率

Table 5. Resolution of the calibrators

	指标	龙伯球	角反射器	理论值
方位向	分辨率(m)	0.1471	0.1478	0.1362
	峰值旁瓣比(dB)	–14.19	–14.04	–13.26
	积分旁瓣比(dB)	–12.45	–12.16	–10.02
距离向	斜距分辨率(m)	0.1241	0.1231	0.1227
	地距分辨率(m)	0.1756	0.1740	0.1735
	峰值旁瓣比(dB)	–13.45	–13.31	–13.26
	积分旁瓣比(dB)	–11.12	–11.21	–10.02

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表 6 斜距误差标定结果

Table 6. Calibration result of slope distance error

方法	$\Delta {R_0}$ (m)	$\Delta {R_1}$ (m/距离门)
有控	1.765427	0.000492772
无控	1.868205	0.000475285

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表 7 两种方法的三维位置偏差(厘米)

Table 7. 3D position deviation of the two methods (cm)

方法	J1	J2	J3	J4	中误差
有控	1.7	8.0	3.2	3.5	4.7
无控	11.8	12.2	8.9	8.9	10.6

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表 8 基线与基线角(T2R2为参考通道)

Table 8. Baseline and baseline angle (T2R2 channel for reference)

参数	T2R2	T2R1	T1R2	T1R1
基线长度(mm)	–	107.10	427.88	534.97
基线角(°)	–	–3.9976	–3.9238	–3.9386

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表 9 通道幅度误差标定结果(T2R2为参考通道)

Table 9. Calibration result of channel amplitude error (T2R2 channel for reference)

参数	T2R2	T2R1	T1R2	T1R1
幅度误差均值(dB)	–	0.0398	0.1238	0.1712
幅度误差峰峰值(dB)	–	±0.049	±0.081	±0.132

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表 10 通道相位误差标定结果

Table 10. Channel phase error calibration results

	常数项(°)	线性项(°/距离门)
接收通道间相位误差(R1-R2)	44.6805	0
发射通道间相位误差(T1-T2)	–6.7496	0.0071068539

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表 11 三维点云的精度及完整性

Table 11. Accuracy and completeness of 3D clouds

	重建精度(m)	重建完整性(m)
ID3重建结果	2.3090	4.9050
ID7重建结果	1.9982	3.9695
两角度融合结果	1.9349	2.7328

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