超长基线星载干涉SAR概念与体制

王祎笛; 王宇; 张云俊; 梁达; 蔡永华; 吴一戎

doi:10.12000/JR25220

超长基线星载干涉SAR概念与体制

DOI: 10.12000/JR25220 CSTR: 32380.14.J25220

王祎笛^{1, 2},
王宇^{1, 2, ,},
张云俊^{1, 2},
梁达²,
蔡永华²,
吴一戎^{1, 2}

1.
中国科学院空天信息创新研究院微波成像国家重点实验室北京 100190
2.
中国科学院大学电子电气与通信工程学院北京 100049

基金项目: 国家自然科学基金(62495030, 62421001)

详细信息

作者简介:
王祎笛，博士生，主要研究方向为干涉SAR信号处理

王　宇，研究员，博士生导师，主要研究方向为新体制航天成像雷达系统技术、微波雷达遥感图像处理和深空微波探测

张云俊，研究员，博士生导师，主要研究方向为干涉SAR信号处理、固体地球物理、地质灾害

梁　达，博士，主要研究方向为双基合成孔径雷达同步与成像处理、微波电磁散射仿真

蔡永华，博士，助理研究员，主要研究方向为分布式SAR同步与成像处理

吴一戎，研究员，中国科学院院士，主要研究方向为微波成像理论与技术、遥感数据信号与图像处理、地理空间信息技术

通讯作者:
王宇 yuwang@mail.ie.ac.cn

责任主编：陈杰 Corresponding Editor: CHEN Jie

中图分类号: TN957.52
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出版历程
- 收稿日期: 2025-11-03
- 修回日期: 2026-01-01
- 网络出版日期: 2026-01-15

The Concept and System of Very Large Baseline Spaceborne Interferometric Synthetic Aperture Radar

WANG Yidi^{1, 2},
WANG Robert^{1, 2
, ,},
ZHANG Yunjun^{1, 2},
LIANG Da²,
CAI Yonghua²,
WU Yirong^{1, 2}

1.
National Key Laboratory of Microwave Imaging, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, China
2.
School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, China

Funds: The National Natural Science Foundation of China (62495030, 62421001)

More Information

Corresponding author: WANG Robert, yuwang@mail.ie.ac.cn

摘要

摘要: 星载干涉合成孔径雷达(InSAR)技术通过测量雷达视线方向的相位差实现地表高程测量与形变监测。然而，面向未来更高精度的干涉测量需求，InSAR系统设计参数与测量精度的解析模型仍存在关键参数不完备、物理约束刻画不充分等问题，对下一代合成孔径雷达干涉测量技术的发展形成制约。该文针对系统设计参数和测量精度间存在的复杂多因素耦合问题开展研究，详细分析了空间、时间基线星载干涉合成孔径雷达成像理论约束关系，构建了融合多源失相干的空-时误差模型，量化了基线参数与测量精度的非线性关系，建立了涵盖相干性、高程精度、基于相干时间基线的形变灵敏度等关键指标的完备评估框架，在此基础上提出了超长基线星载InSAR的概念与体制。同时，对超长基线星载InSAR的性能进行了详细分析，阐述了超长基线星载InSAR在轨道设计、系统设计、同步方法、误差校正以及相位解缠等方面的技术挑战，介绍了超长基线星载InSAR在高精度高程测量与形变测量以及分布式SAR系统等方面的应用潜力，可为未来新一代高精度、多维度InSAR系统设计提供理论支撑，在地球科学前沿探索与国家重大工程安全保障中发挥更大价值。
- 干涉合成孔径雷达 /
- 超长基线 /
- 高精度高程测量 /
- 高精度形变测量 /
- 系统设计
Abstract: Spaceborne Interferometric Synthetic Aperture Radar (InSAR) enables surface elevation measurement and deformation monitoring by measuring phase differences along the radar line of sight. However, meeting the future demand for higher-precision measurements remains challenging: analytical models linking InSAR system design parameters to measurement accuracy are still limited by incomplete key parameters and insufficient or unclear physical constraints. These limitations restrict the development of next-generation InSAR technology. This study examines the complex multifactor coupling between system design parameters and measurement accuracy. It provides a detailed analysis of the imaging mechanism and theoretical constraints of spaceborne InSAR with spatial and temporal baselines and presents a spatiotemporal error model integrating multisource decorrelation. The nonlinear relationship between baseline parameters and measurement accuracy is quantitatively characterized, and a comprehensive evaluation framework is established based on key indicators such as coherence, elevation accuracy, and coherent temporal baseline-based deformation sensitivity. Built on top of these analysis, the concept and system architecture of very large baseline spaceborne InSAR are proposed, and its performance is analyzed in detail. The associated technical challenges—including orbit configuration, system design, synchronization, error correction, and phase unwrapping—are systematically discussed. Potential applications of this type of InSAR system architecture in high-precision elevation, deformation measurements, and distributed SAR systems are introduced. The proposed framework provides theoretical support for the design of next-generation high-precision, multidimensional InSAR systems and is expected to play a key role in the frontier of Earth science exploration and the safety assurance of major national engineering projects.
- Interferometric Synthetic Aperture Radar (InSAR) /
- Very large baseline /
- High-precision elevation measurement /
- High-precision deformation measurement /
- System design

HTML全文

图 1 超长基线合成孔径雷达干涉测量

Figure 1. Very large baseline synthetic aperture radar interferometry

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图 2 临界有效基线解析方程(灰色阴影区为5%相对误差邻域)

Figure 2. Analytical equation for critical effective baseline (the gray shaded area denotes the 5% relative error neighborhood)

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图 3 不同参数变化对临界有效基线取值的影响

Figure 3. Influence of different parameter variations on the value of critical effective baseline

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图 4 Sentinel-1在不同地物类型的相干性

Figure 4. Coherence of Sentinel-1 in different land cover types

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图 5 超长基线InSAR概念

Figure 5. Concept of very large baseline InSAR

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图 6 干涉条纹密集程度与基线的变化关系

Figure 6. Relationship between the density of interferometric fringes and baseline variation

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图 7 高程误差随有效基线因子的变化关系

Figure 7. Relationship between elevation error and effective baseline factor

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图 8 相干性随时间基线的变化关系

Figure 8. Relationship between coherence and the temporal baseline

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图 9 平均相干性与形变测量精度的关系

Figure 9. Relationship between average coherence and deformation measurement accuracy

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图 10 超长基线InSAR技术挑战概念图

Figure 10. Concept map of technical challenges in very large baseline InSAR

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图 11 轨道设计与控制示意图

Figure 11. Schematic diagram of orbit design and control

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图 12 机载DBF实验验证结果^[49]

Figure 12. Airborne DBF experimental verification results^[49]

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图 13 LuTan-1的NLFM波形数据获得的聚焦图像^[56]

Figure 13. Focused images obtained from LuTan-1’s NLFM waveform data^[56]

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图 14 脉冲交换方案示意图

Figure 14. Schematic diagram of pulse exchange scheme

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图 15 陆探一号同步抗干扰处理前后成像结果^[68]

Figure 15. LuTan-1 imaging results before and after synchronous anti-interference processing^[68]

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图 16 对流层延迟校正前和用不同方法校正后的干涉相位^[71]

Figure 16. Interference phase before tropospheric delay correction and after correction using different methods^[71]

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图 17 基于谱分集方法校正L波段ALOS-2电离层延迟相位

Figure 17. Ionospheric delay phase correction of L-band ALOS-2 based on split-spectrum method

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图 18 基于深度学习的相位解缠示例^[77]

Figure 18. Example of phase unwrapping based on deep learning^[77]

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图 19 TanDEM-X和LuTan-1在典型系统参数(见表4)条件下，不同地表覆盖类型下的高程误差

Figure 19. Elevation errors of TanDEM-X and LuTan-1 under different land cover types with typical system parameters (see Tab. 4)

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图 20 不同波段、不同地物类型的相干性影响的形变速率测量精度

Figure 20. Deformation velocity measurement accuracy affected by coherence under different frequency bands and different land cover types

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图 21 L波段与S波段之间的精度差异

Figure 21. Accuracy difference between L-band and S-band

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图 22 基于LuTan-1数据的DEM产品

Figure 22. DEM product based on LuTan-1 data

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图 23 山西省大同市矿区基于LuTan-1数据的形变结果^[82]

Figure 23. Deformation results based on LuTan-1 data in the mining area of Datong, Shanxi^[82]

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表 1 基于临界有效基线解析方程的EBF分类标准

Table 1. Classification standard for EBF based on the analytical equation of critical effective baseline

条件	定义	基线类型	物理意义
$ {\mathrm{d}}{\sigma }_{h}/{\mathrm{d}}{\varOmega } > 0 $	$ {\varOmega } > 27\mathrm{\% } $	无效空间基线	失相干成为误差主导因素，此时高程测量相位误差急剧上升，严重失相干导致测量结果不可信
$ {\mathrm{d}}{\sigma }_{h}/{\mathrm{d}}{\varOmega }=0 $	$ {\varOmega }=26\mathrm{\% }-27\mathrm{\% } $	临界有效空间基线	作为高程误差随EBF变化的分界点，是高程误差收敛至全局最小值(精度最高)的理论边界点；是基线增益与失相干损耗的平衡临界点，标志误差主导因素本质转变；是InSAR系统精度调控拐点，提供量化基线参数最优阈值，对应精度最优状态
$ \begin{aligned}& {\rm d}{\sigma }_{h}/{\rm d }{\varOmega } < 0\\& 且{\varOmega } > 10\mathrm{\% }\end{aligned} $	$ 10\mathrm{\% } < {\varOmega } < 26\mathrm{\% } $	超长空间基线	导数变化变缓，高程精度对基线长度变化仍敏感，但开始出现相干性造成的误差抵消高程精度的提升，控制误差优于提升基线长度，需严格把控失相干误差的影响
$ {\varOmega }\leq 10\mathrm{\% } $	$ {\varOmega }\leq 10\mathrm{\% } $	传统空间基线^[15,17,18]	即传统短基线和长基线。导数快速变化，基线增益起主导作用，高程精度对基线长度变化敏感

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表 2 基于临界相干时间基线模型的时间基线分类标准

Table 2. Classification standard for temporal baseline based on the critical coherence temporal baseline model

定义	基线类型	物理意义
$ t > \mu $	无效时间基线	超出临界相干时间基线，相干性趋近长期值且变化极缓，继续增加基线无显著增益且浪费资源
$ t=\mu $	临界相干时间基线	相干性衰减速率由快转缓的临界转变点，标志向长期稳定态过渡的理论分界
$ \mu \ln 2 < t < \mu $	超长时间基线	长期相干性主导衰减过程，散射体长期统计特性为主要控制因素
$ t=\mu \ln 2 $	超长时间基线临界点	相干性从短期初始状态主导向长期稳定特性主导过渡的关键节点
$ 0 < t < \mu \ln 2 $	传统时间基线	即传统短基线和长基线。初始相干性主导衰减过程，系统参数设计为主要控制因素，相干性保持较高水平

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表 3 不同波段、不同地物类型的临界相干时间基线和超长时间基线临界点

Table 3. Critical coherent temporal baseline and very large temporal baseline critical point for different wavebands and different land cover types

波段	临界相干时间基线(d)			超长时间基线临界点(d)
波段	森林	农田	裸土	森林	农田	裸土
L波段	185	444	536	128	308	371
S波段	29	68	83	20	47	57
C波段	10	24	29	7	17	20
X波段	3	8	9	2	5	6

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表 4 TanDEM-X和LuTan-1的典型参数

Table 4. Typical parameters of TanDEM-X and LuTan-1

参数	TanDEM-X	LuTan-1
NESZ	–19 dB	–28 dB
入射角	35°	35°
距离向带宽	100 MHz	80 MHz

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