天基穿冰雷达系统：机遇与挑战

肖鹏; 于志同; 陈卓奇; 崔祥斌; 赵博; 稂时楠; 李萌; 胡洛佳; 黄彦; 刘敏; 王成; 陈亮; 刘露; 眭晓虹; 袁春柱

doi:10.12000/JR21196

天基穿冰雷达系统：机遇与挑战

DOI: 10.12000/JR21196

肖鹏^1, ,,
于志同^1, ,,
陈卓奇²,
崔祥斌³,
赵博⁴,
稂时楠⁵,
李萌¹,
胡洛佳¹,
黄彦¹,
刘敏¹,
王成¹,
陈亮¹,
刘露¹,
眭晓虹¹,
袁春柱⁶

1.
中国空间技术研究院钱学森空间技术实验室北京 100094
2.
中山大学测绘科学与技术学院珠海 519082
3.
中国极地研究中心上海 200136
4.
中国科学院空天信息创新研究院北京 100094
5.
北京工业大学信息学部北京 100124
6.
中国空间技术研究院航天东方红卫星有限公司北京 100094

基金项目: 东方红联合研发基金，五院杰出青年人才基金，国家自然科学基金(42074225, 41601483, 41730102)

详细信息

作者简介:
肖　鹏(1984–)，男，黑龙江哈尔滨人，博士，高级工程师。2014 年在北京航空航天大学电子信息工程学院获得博士学位，现为中国空间技术研究院钱学森空间技术实验室高级工程师。主要研究方向为新型星载合成孔径雷达系统设计、先进雷达信号处理、高分辨率微波遥感图像质量提升与应用等，目前已发表学术论文 20余篇

于志同(1985–)，男，河北衡水人，博士，副研究员。2015年在中国科学院大学获得博士学位，现为中国空间技术研究院钱学森空间技术实验室高级工程师、PI。主要研究方向为全球变化天基观测、生物地球化学、碳循环，目前已出版专著1部、发表论文30余篇

陈卓奇(1982–)，男，江西南昌人，博士，副教授。2009年在中国科学院地理科学与资源研究所获得博士学位，现为中山大学测绘科学与技术学院副教授。主要研究方向为全球变化、碳循环，目前已发表论文50余篇

崔祥斌(1981–)，男，山西朔州人，博士，研究员。2010年获浙江大学地质资源与地质工程专业博士学位，现为中国极地研究中心极地冰雪与气候变化研究所研究员，主要研究方向为南极雷达冰川学，发表论文70多篇

赵　博(1983–)，男，山西芮城人，博士，副研究员。2009年获中国科学院电子学研究所电磁场与微波技术专业博士学位，现为中国科学院空天信息创新研究院副研究员，主要研究方向为超宽带雷达技术，发表论文20余篇

稂时楠(1988–)，女，陕西汉中人，博士，副教授。2015年获中国科学院电子学研究所电磁场与微波技术专业博士学位，现为北京工业大学信息学部副教授。主要研究方向为冰雷达成像与数据处理方法，发表论文30多篇

李　萌(1985–)，男，吉林扶余人，博士，研究员。2013年在哈尔滨工业大学宇航空间机构及控制研究中心获得工学博士学位，现为钱学森空间技术实验室研究员。主要研究方向为空间大型可展天线、星球探测着陆缓冲技术，发表论文30余篇，出版专著2部

胡洛佳(1990–)，女，山西太原人，博士，助理研究员。2018年在北京师范大学全球变化与地球科学研究院获得博士学位，现为钱学森空间技术实验室助理研究员。主要研究方向为海岸带遥感、星载激光雷达系统模拟仿真及数据应用

黄　彦(1985–)，女，四川汶川人，博士，助理研究员。2015年在南京大学国际地球系统科学研究所获博士学位，现为钱学森空间技术实验室助理研究员。主要研究方向为全球变化遥感，已发表论文30余篇

刘　敏(1986–)，女，重庆合川人，博士，高级工程师。2014年在北京航空航天大学电子信息工程学院获得博士学位。现就职于钱学森空间技术实验室军事智能信息体系研究室。主要研究方向为星载合成孔径雷达SAR成像处理，包括各种成像算法研究、图像质量提升、星载SAR图像定位等。目前已发表论文10多篇

王　成(1988–)，男，陕西西安人，博士，副研究员。2015年在西安电子科技大学物理与光电工程学院获得博士学位，现为中国空间技术研究院钱学森空间技术实验室副研究员。主要研究方向为电波传播、电离层误差探测与补偿，目前已发表论文20余篇

陈　亮(1982–)，男，河南信阳人，博士，高级工程师。2009年在中国科学院获得博士学位，现为中国空间技术研究院钱学森空间技术实验室高级工程师，主要研究方向为微波遥感系统仿真、参数定量反演

刘　露(1988–)，男，安徽六安人，博士，副研究员。2015年在北京航空航天大学数学学院获得博士学位，现为钱学森空间技术实验室副研究员。主要研究方向为压缩感知、机器学习理论、遥感图像智能处理及目标识别，目前已发表论文27篇，受理或授权11项发明专利

眭晓虹(1988–)，女，山西晋中人，博士，工程师。2017年在中国空间技术研究院飞行器设计专业获博士学位，现就职于钱学森空间技术实验室。主要研究方向为海洋测高卫星应用、海洋重力场与海底地形反演

袁春柱(1987–)，男，山西临沂人，硕士，高级工程师。2011年在北京航空航天大学仪器科学与技术专业获硕士学位，现就职于航天东方红卫星有限公司。主要研究方向为卫星总体设计

通讯作者:
肖鹏 xiaopeng_email1984@163.com

于志同 yuzhitong@qxslab.cn

责任主编：刘小军 Corresponding Editor: LIU Xiaojun
中图分类号: TN958
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出版历程
- 收稿日期: 2021-11-30
- 修回日期: 2022-01-11
- 网络出版日期: 2022-02-24
- 刊出日期: 2022-06-28

Orbital Radar Sounding of Earth’s Ice Sheets: Opportunities and Challenges

1.
Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing 100094, China
2.
School of Geospatial Engineering and Science, Sun Yat-Sen University, Zhuhai 519082, China
3.
Polar Research Institute of China, Shanghai 200136, China
4.
Aerospace Information Research Institute, Chinese Academy of Science, Beijing 100094, China
5.
Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China
6.
DFH Satellite Co., Ltd., China Academy of Space Technology, Beijing 100094, China

Funds: DFH Joint Research and Development Fund, Young Talents Fund of China Academy of Space Technology, The National Natural Science Foundation of China (42074225, 41601483, 41730102)

More Information

Corresponding author: XIAO Peng, xiaopeng_email1984@163.com; YU Zhitong, yuzhitong@qxslab.cn

摘要

摘要: 极地冰盖特殊的热交换属性和庞大的含水量，使其成为全球气候变化的“指示器”和“放大器”。由于特殊的地理位置及严峻的气候环境，目前对极地冰盖的立体探测及认识仍旧匮乏。穿冰雷达具备强穿透性和高精度测距能力，成为冰盖立体层析探测的最佳选择，促进了极地科学的快速发展。受制于低频电磁波跨冰冻圈层传播的复杂性和雷达作用距离的大幅增加，迄今为止，利用天基平台实现穿冰探测依然是对地遥感的空白领域。该文针对天基穿冰雷达系统的科学需求和面临的特殊问题展开讨论，分析了天基穿冰系统面临的3大问题：传输衰减、积雪杂波干扰和垂直航迹向分辨率恶化；结合现有研究成果和技术发展趋势，分析了利用微小卫星平台进行分布式编队实现天基穿冰探测的可行性，论证了分布式穿冰雷达关键指标，指出了天基穿冰雷达未来发展亟需解决的关键技术难题，探索实现百米空间分辨率、季节尺度重访的天基穿冰雷达实施方案。
- 天基穿冰雷达 /
- 层析探测 /
- 分布式雷达 /
- 极地冰盖 /
- 全球气候变化
Abstract: Owing to the enormous amount of frozen water and the particularity of heat exchange, polar ice sheets act as an important indicator and amplifier of global climate change. However, the detection and cognition of the tomographic structure of polar ice sheets remain insufficient due to the special geographical location and harsh weather. Benefit from the advantage of strong penetrability and high-precision range measurement, the ice sounding radar is an optimal instrument for tomographic detection of polar ice sheets, which significantly promotes the development of polar science. Nevertheless, existing radar satellites still cannot detect ice beds in depth because of the complex low-frequency signal propagation in ice and an extremely long operating distance. This study focuses on the scientific objectives (spatial resolution: 100 m and revisit time: 3 months) and presents an in-depth analysis of the key problems of orbital ice sounding radar, including transmission attenuation, firn clutter, and cross-track resolution deterioration. With reference to the current state and trend of radar satellite technology, we proved the feasibility of the application of distributed Synthetic Aperture Radar (SAR) on the microsatellite platform for ice bed detection, identified the key parameters of distributed SAR and the technical challenges of orbital radar sounding system for polar ice sheet tomographic observation, and further explored the implementation scheme.
- Orbital ice sounding radar /
- Tomography /
- Distributed radar /
- Polar ice sheets /
- Global climate change

HTML全文

图 1 机载穿冰雷达观测示意图

Figure 1. Schematic diagram of airborne ice sounding radar observation

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图 2 南极冰盖层析图像(中科院电子所穿冰雷达系统)

Figure 2. A tomographic image of the Antarctic ice sheet obtained by the ice sounding radar developed by the Chinese Academy of Sciences

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图 3 “雪鹰601”科学调查平台

Figure 3. “Snow Eagle 601” scientific investigation platform

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图 4 Bedmap2数据库示意图^[28]

Figure 4. Bedmap2 database diagram^[28]

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图 5 WMO-GCW天基冰冻圈观测计划及能力^[36]

Figure 5. WMO-GCW spaceborne cryosphere observation programs and capabilities^[36]

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图 6 火星探测雷达

Figure 6. Mars sounding radars

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图 7 JPL OASIS计划

Figure 7. JPL’s OASIS program

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图 8 不同频率下南极冰盖冰衰减估算结果

Figure 8. Ice attenuation estimations of the Antarctic ice sheet with different frequencies

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图 9 穿冰雷达积雪杂波干扰示意图

Figure 9. Schematic diagram of snow clutter jamming for ice sounding radar

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图 10 “雪鹰601”穿冰雷达积雪杂波干扰示意图

Figure 10. Snow clutter interference of “snow Eagle 601” ice sounding radar

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图 11 VHF频段积雪杂波强度空间分布特性(基于“雪鹰601”实测数据)

Figure 11. Spatial distribution characteristics of snow clutter intensity based on “snow Eagle 601” data

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图 12 天基条件下杂波抑制需求曲线

Figure 12. Clutter suppression demand for spaceborne radar

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图 13 DEBRIS系统示意图^[59]

Figure 13. DEBRIS system schematic^[59]

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图 14 STRATUS系统

Figure 14. STRATUS system

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图 15 CubeSat Train系统^[61]

Figure 15. CubeSat Train system^[61]

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图 16 空间收发角度示意图

Figure 16. Spatial transmitting and receiving angles diagram

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图 17 垂直航迹向分辨率与卫星数量

Figure 17. Cross-track direction resolution with the number of satellites

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表 1 PRISM科学测量体系^[35]

Table 1. PRISM scientific measurement system^[35]

测量参数	相关科学目标	要求精度	空间分辨率(m)	传感器
冰厚	1, 2	5 m	100(普查)、10(详查)	宽带穿冰雷达
冰底消融/冻结	3	95%可信度	100	单基/双基SAR
底部水层及厚度	3, 4	50%以上准确度、4 mm～0.5 m	100(普查)、10(详查)	单基/双基SAR
内部层	5, 2, 6	10 cm(浅部)、5 m(深部)	100(普查)、10(详查)	宽带穿冰雷达
冰下地形	2	5 m	100(普查)、10(详查)	宽带穿冰雷达
冰面地形	2	0.5 m	100(普查)、10(详查)	InSAR，雷达/激光高度计，GPS
冰流速度	1, 2, 6	5%(速度)、5°(方向)	500	InSAR
注：科学目标：1. 物质通量；2. 应力估计；3. 底部边界条件；4. 底部剪应力；5. 积累率；6. 冰流历史

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表 2 次表层探测雷达卫星参数

Table 2. The paramenters of sounding radar satellites

参数	MARSIS^[40]	SHARAD^[41]	OASIS^[44]
频率范围(MHz)	2.5～3.5(较多使用)	15～25	40～50
地下垂直分辨率(m) (相对介电常数为3时)	～100	～10	～10
航迹向分辨率(km)	5～15	0.3～3.0	～1
垂直航迹向分辨率(km)	9～30	1～7	/
预期穿透能力(km)	0.5～5.0	0.1～1.0	0.1(沙漠)～5.0(冰)
发射功率(W)	5	10	100
天线长度(m)	40(偶极子天线)	10(偶极子天线)	10(八木天线)

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表 3 Fujita参数表1^[47]

Table 3. Fujita parameters table 1^[47]

温度(K)	$A (\times {10^4})$	$B (\times {10^5})$	$C$
190	0.005	1.537	1.175
200	0.010	1.747	1.168
220	0.031	2.469	1.129
240	0.268	3.495	1.088
248	0.635	4.006	1.073
253	1.059	4.380	1.062
258	1.728	4.696	1.056
263	2.769	5.277	1.038
265	3.326	5.646	1.024

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表 4 Fujita参数表2^[47]

Table 4. Fujita parameters table 2^[47]

温度(K)	$a$	$b$
263	4.283	–0.337
253	4.875	–0.423
243	5.279	–0.480
233	4.996	–0.456

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表 5 天基与机载穿冰雷达相关参数对比

Table 5. The paramenters of spaceborne and airborne ice sounding radars

参数	天基系统	机载系统	差异
飞行高度	500 km	500 m	/
载频波长	5 m	5 m	/
传播衰减	/	/	90 dB
积雪杂波干扰深度	冰底以下	280 m
垂直航迹向分辨率	2.2 km	180 m

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表 6 分布式穿冰雷达系统

Table 6. Distributed orbital ice sounding radar systems

参数	DEBRIS^[59]	STRATUS^[60]	CubeSat Train^[61]
载频(MHz)	45, 435	45	144
星群数量	11颗(多发多收)	1+4颗(一发多收)	50颗(多发多收)
发射功率(W)	未知	800	50
天线尺寸(m)	3.3×3.3 四组柔性反射天线	10 八木天线阵	15 多通道十字天线
飞行高度(km)	400	500	400
预期穿冰深度(km)	<5	4.7	3～4
冰内垂直分辨率(m)	10	10	20
水平分辨率(航迹向×垂直航迹向)	1 km×20 km	1.3 km×7.5 km	200 m×200 m

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